Quantenna Communications (QTNA) 10-K 1 Mar 19 2018 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 30, 2018	Feb. 26, 2019	Jun. 29, 2018
Document and Entity Information [Abstract]
Entity Registrant Name	QUANTENNA COMMUNICATIONS INC
Entity Central Index Key	1,370,702
Current Fiscal Year End Date	--12-30
Entity Filer Category	Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	FY
Entity Public Float			$ 506,823,969
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Amendment Flag	false
Entity common stock, shares outstanding		38,261,220
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Shell Company	false
Entity Ex Transition Period	true

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 30, 2018	Dec. 31, 2017
Current assets
Cash and cash equivalents	$ 38,881	$ 24,432
Marketable securities	97,268	94,195
Accounts receivable	28,326	26,786
Inventory	20,218	12,662
Prepaid expenses and other current assets	5,325	2,744
Total current assets	190,018	160,819
Deferred tax assets, net	35,563	35,422
Property and equipment, net	13,691	12,511
Intangible and other assets, net	6,384	3,952
Total assets	245,656	212,704
Current liabilities
Accounts payable	9,852	3,754
Accrued liabilities and other current liabilities	25,946	21,065
Long-term debt, current portion	0	3,943
Total current liabilities	35,798	28,762
Other long-term liabilities	3,371	3,339
Total liabilities	39,169	32,101
Commitments and contingencies (see Note 7)
Stockholders’ equity
Common stock: $0.0001 par value, 1,000,000,000 shares authorized at December 30, 2018 and December 31, 2017, 37,695,109 and 35,528,880 shares issued and outstanding at December 30, 2018 and December 31, 2017, respectively	4	3
Additional paid-in capital	331,551	308,023
Accumulated other comprehensive loss	(935)	(207)
Accumulated deficit	(124,133)	(127,216)
Total stockholders’ equity	206,487	180,603
Total liabilities and stockholders’ equity	$ 245,656	$ 212,704

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 30, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Common stock, par value (in usd per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock, shares issued (in shares)	37,695,109	35,528,880
Common stock, shares outstanding (in shares)	37,695,109	35,528,880

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Income Statement [Abstract]
Revenue	$ 220,460	$ 176,359	$ 129,069
Cost of revenue	111,058	88,208	64,640
Gross profit	109,402	88,151	64,429
Operating expenses:
Research and development	71,522	59,747	46,604
Sales and marketing	16,303	14,040	8,091
General and administrative	18,767	15,299	10,559
Total operating expenses	106,592	89,086	65,254
Income (loss) from operations	2,810	(935)	(825)
Interest expense	0	(713)	(665)
Other income (expense), net	1,239	1,118	(38)
Income (loss) before income taxes	4,049	(530)	(1,528)
Benefit (provision) for income taxes	(966)	34,942	(367)
Net income (loss)	$ 3,083	$ 34,412	$ (1,895)
Net income (loss) per share:
Basic (dollars per share)	$ 0.08	$ 1	$ (0.30)
Diluted (dollars per share)	$ 0.08	$ 0.89	$ (0.30)
Weighted-average number of shares used in per share calculations:
Basic (shares)	36,744	34,259	6,385
Diluted (shares)	39,663	38,484	6,385

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 3,083	$ 34,412	$ (1,895)
Other comprehensive loss, net of tax:
Unrealized gains (losses) on available-for-sale marketable securities	57	(207)	0
Unrealized losses on derivative instruments	(785)	0	0
Other comprehensive loss, net of tax	(728)	(207)	0
Comprehensive income (loss)	$ 2,355	$ 34,205	$ (1,895)

Consolidated Statements of Conv

Consolidated Statements of Convertible Preferred Stock and Stockholders’ Equity (Deficit) - USD ($) $ in Thousands	Total	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit	Convertible Preferred Stock	Common Stock
Beginning balance (in shares) at Dec. 27, 2015					22,471,537	1,106,240
Beginning, stockholders' equity at Dec. 27, 2015	$ (155,672)	$ 4,007	$ 0	$ (159,679)	$ 184,704	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock for exercise of options (in shares)						329,017
Issuance of common stock for exercise of options	579	579
Issuance of common stock for service provided (in shares)						2,777
Issuance of common stock for service provided	25	25
Proceeds from initial public offering, net of issuance costs (in shares)						6,775,466
Proceeds from initial public offering, net of issuance costs	97,419	97,418				$ 1
Conversion of preferred stock to common stock pursuant to IPO (in shares)					22,471,537	24,790,650
Conversion of preferred stock to common stock pursuant to IPO	184,704	184,702			$ 184,704	$ 2
Conversion of preferred stock warrants to common stock warrants	342	342
Issuance of common stock upon exercise of options subject to repurchase (in shares)						72,000
Vesting of options subject to repurchase	85	85
Stock-based compensation expense	3,065	3,065
Issuance of common stock warrants	96	96
Net income (loss)	(1,895)			(1,895)
Ending balance (in shares) at Jan. 01, 2017					0	33,076,150
Ending, stockholders' equity at Jan. 01, 2017	128,748	290,319	0	(161,574)	$ 0	$ 3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment of ASU 2016-09 (Note 1)		54		(54)
Issuance of common stock for exercise of options (in shares)						2,452,730
Issuance of common stock for exercise of options	7,253	7,253
Stock-based compensation expense	10,683	10,683
Issuance costs related to initial public offering	(286)	(286)
Change in unrealized loss on marketable securities, net of tax	(207)		(207)
Net income (loss)	34,412			34,412
Ending balance (in shares) at Dec. 31, 2017					0	35,528,880
Ending, stockholders' equity at Dec. 31, 2017	180,603	308,023	(207)	(127,216)	$ 0	$ 3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock for exercise of options (in shares)						2,166,229
Issuance of common stock for exercise of options	6,240	6,239				$ 1
Stock-based compensation expense	17,289	17,289
Change in unrealized loss on marketable securities, net of tax	57		57
Change in unrealized loss on derivative instruments, net of tax	(785)		(785)
Net income (loss)	3,083			3,083
Ending balance (in shares) at Dec. 30, 2018					0	37,695,109
Ending, stockholders' equity at Dec. 30, 2018	$ 206,487	$ 331,551	$ (935)	$ (124,133)	$ 0	$ 4

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Cash flows from operating activities
Net income (loss)	$ 3,083	$ 34,412	$ (1,895)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Stock based compensation	17,289	10,683	3,065
Depreciation and amortization	4,861	2,669	1,278
Deferred income taxes	53	(35,333)	0
Other	1,067	635	434
Changes in assets and liabilities:
Accounts receivable	(1,540)	(12,306)	1,237
Inventory	(7,556)	3,158	(8,413)
Prepaid expenses and other current assets	(2,581)	(335)	(901)
Deferred rent and other assets	313	(467)	(50)
Accounts payable	5,791	(5,752)	1,804
Accrued liabilities and other current liabilities	4,040	9,265	5,757
Net cash provided by operating activities	24,820	6,629	2,316
Cash flows from investing activities
Purchase of property and equipment	(5,100)	(8,970)	(2,724)
Purchase of long-term investment	(590)	0	0
Purchase of intangible asset	(1,732)	0	0
Purchase of marketable securities	(69,716)	(131,790)	0
Proceeds from sales and maturities of marketable securities	66,173	37,124	0
Restricted cash	0	0	(59)
Net cash used in investing activities	(10,965)	(103,636)	(2,783)
Cash flows from financing activities
Proceeds from issuance of common stock	8,418	7,675	1,191
Payment of taxes withheld for vested stock awards	(2,501)	(626)	0
Proceeds from initial public offering, net of issuance costs	0		97,483
Proceeds from initial public offering, net of issuance costs		(96)
Proceeds from revolving line of credit, net of fees paid	0	0	2,950
Repayment of revolving line of credit	0	0	(3,000)
Proceeds from issuance of long-term debt, net of fees paid	0	0	3,854
Payments related to intangible asset purchase	(1,086)	(266)	0
Repayments of long-term debt	(3,943)	(2,406)	(3,816)
Net cash provided by financing activities	888	4,281	98,662
Effect of exchange rate changes on cash and cash equivalents	(294)	113	0
Net increase (decrease) in cash and cash equivalents	14,449	(92,613)	98,195
Beginning of year	24,432	117,045	18,850
End of year	38,881	24,432	117,045
Supplemental disclosure of cash flow information
Interest paid during the period	0	224	489
Income taxes paid during the period	455	278	106
Supplemental disclosure of non-cash investing and financing activities
Purchases of property and equipment included in accounts payable and accrued liabilities and other current liabilities	193	433	213
Intangible assets, capitalized	1,650	3,259	0
Conversion of convertible preferred stock to common stock
Supplemental disclosure of non-cash investing and financing activities
Conversion of convertible preferred stock to common stock	$ 0	$ 0	$ 184,704

The Company and Summary of Sign

The Company and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
The Company and Summary of Significant Accounting Policies	The Company and Summary of Significant Accounting Policies Quantenna Communications, Inc. (the “Company”) was incorporated in the State of Delaware on November 28, 2005. The Company designs, develops and markets advanced high-speed wireless communication solutions enabling wireless local area networking. The Company’s solutions are designed to deliver leading-edge Wi-Fi performance to support an increasing number of connected devices accessing a rapidly growing pool of digital content. The Company applies its wireless systems and software expertise with high-performance radio frequency, mixed-signal and digital semiconductor design skills to provide highly integrated Wi-Fi solutions to its customers. Reporting Calendar The Company prepares financial statements on a 52- or 53-week fiscal year that ends on the Sunday closest to December 31. The fiscal years ended on December 30, 2018 , December 31, 2017 and January 1, 2017 consisted of 52 weeks, 52 weeks and 53 weeks, respectively. Fiscal 2019 consists of 52 weeks ending on December 29, 2019. Use of Estimates Preparation of financial statements in conformity with accounting principles generally accepted in the United States of America, or US GAAP, requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and reported amounts of revenue and expenses during the reporting periods covered by the financial statements and accompanying notes. Among the significant estimates affecting the financial statements are those related to inventories, revenue recognition, stock-based compensation and income taxes. Actual results could differ from those estimates. Principles of Consolidation The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany transactions and balances have been eliminated in consolidation. Foreign Currency Remeasurement The Company and its subsidiaries use the U.S. dollar as the functional currency. Foreign currency assets and liabilities are remeasured into U.S. dollars at the end-of-period exchange rates except for non-monetary assets and liabilities, which are measured at historical exchange rates. Revenue and expenses are remeasured using an average exchange rate for the respective period, except for expenses related to non-monetary assets and liabilities, which are measured at historical exchange rates. Gains or losses from foreign currency remeasurement and transactions are included in “Other income (expense), net”. For the years ended December 30, 2018 , December 31, 2017 and January 1, 2017 , foreign currency remeasurement and transactions gains and losses were immaterial. Cash and Cash Equivalents Cash equivalents include liquid short-term investments with original or remaining maturities of three months or less at the date of purchase, readily convertible to known amounts of cash. Marketable Securities Marketable securities consist primarily of highly liquid investments with maturities of greater than 90 days when purchased. We generally classify our marketable securities at the date of acquisition as available-for-sale. These securities are reported at fair value with the related unrealized gains and losses included in " Accumulated other comprehensive loss ", a component of stockholders’ equity, net of tax. Any unrealized losses which are considered to be other-than-temporary impairments are recorded in " Other income (expense), net " in the Consolidated Statements of Operations. Realized gains (losses) on the sale of marketable securities are determined using the specific-identification method and recorded in " Other income (expense), net " in the Consolidated Statements of Operations. All of our available-for-sale investments are subject to a periodic impairment review. We record a charge to earnings when a decline in fair value is significantly below cost basis and judged to be other-than-temporary, or have other indicators of impairments. If the fair value of an available-for-sale investment is less than its amortized cost basis, an other-than-temporary impairment is triggered in circumstances where (1) we intend to sell the instrument, (2) it is more likely than not that we will be required to sell the instrument before recovery of its amortized cost basis or (3) a credit loss exists where we do not expect to recover the entire amortized cost basis of the instrument. If we intend to sell or it is more likely than not that we will be required to sell the available-for-sale investment before recovery of its amortized cost basis, we recognize an other-than temporary impairment charge equal to the entire difference between the investment's amortized cost basis and its fair value. Derivative Financial Instruments The Company uses derivative instruments to manage its exposure to changes in foreign currency exchange rates from forecasted cash flows associated with the operational expenses of its foreign subsidiaries. Derivative instruments are measured at their fair values and recognized as either assets or liabilities. The Company’s derivative forward contracts are designated as cash-flow hedges and their effectiveness is measured by comparing the cumulative forward-rate changes in the fair value of the hedge contract with the cumulative forward-rate change in the forecasted cash flows of the hedged item. See Note 6 , “Derivative Instruments,” of the Notes to Consolidated Financial Statements included elsewhere in this Annual Report on Form 10-K for further details. Fair Value of Financial Instruments The carrying amounts of the Company’s financial instruments, which include cash equivalents, accounts receivable, accounts payable and accrued liabilities and other current liabilities, approximate their fair values due to their short maturities. Estimates of fair value of our marketable securities are based on quoted market prices from active markets or third party, market-based pricing sources which we believe to be reliable. Derivative instruments are measured at their fair values and recognized as either assets or liabilities. See Note 5 , “Fair Value Measurements,” of the Notes to Consolidated Financial Statements included elsewhere in this Annual Report on Form 10-K for further details. Accounts Receivable and Allowances for Doubtful Accounts Accounts receivable are stated at invoice value less estimated allowances for returns and doubtful accounts. The Company continually monitors customer payments and maintains an allowance for estimated losses resulting from its customers’ inability to make required payments. The Company considers factors such as historical experience, credit quality, age of the accounts receivable balances, geographic related risks and economic conditions that may affect a customer’s ability to pay. In cases where there are circumstances that may impair a specific customer’s ability to meet its financial obligations, a specific allowance is recorded against amounts due, which reduces the net recognized receivable to the amount reasonably believed to be collectible. For all periods presented, the Company concluded that no allowance for doubtful accounts was necessary and therefore no amounts were recorded as bad debt provision. Concentration of Credit Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist principally of cash and cash equivalents, marketable securities and accounts receivable. We invest our excess cash primarily in banks, money market funds, government debt securities and corporate debt securities. We have established guidelines relative to credit ratings, diversification and maturities that seek to maintain safety and liquidity. The Company generally requires no collateral from its customers. For the years ended December 30, 2018 , December 31, 2017 and January 1, 2017 , one , one and three customers accounted for 10% or more of revenue, respectively. The following table discloses these customers’ percentage of revenue for the respective periods: Years Ended December 30, December 31, January 1, Customer A 29% 16% 11% B * * 19% C * * 11% * Total customer percentage of revenue was less than 10% . The following table discloses customer balances that accounted for 10% or more of accounts receivable: December 30, December 31, Customer A 36% 31% B 14% * C * 12% D 10% * E 10% 14% Inventory Inventory is stated at the lower of cost to purchase or manufacture the inventory or the market value of such inventory. Cost is determined using the standard cost method which approximates the first-in first-out basis. Market value is determined as the lower of replacement cost or net realizable value. The Company, at least quarterly, assesses the recoverability of all inventories to determine whether adjustments are required to record inventory at the lower of cost or market. Potentially excess and obsolete inventory is written off based on management’s analysis of inventory levels and estimates of future 12-month demand and market conditions. The Company is also entitled to receive rebates from its foundry partner on the purchase of silicon wafers upon achieving certain volume targets. Rebates from the Company’s foundry partner are recorded as a reduction of inventory cost when it is probable and reasonably estimable, and are recognized in cost of revenue as the chipsets made from such silicon wafers are sold to customers. Property and Equipment Property and equipment are stated at cost and depreciated using the straight‑line method over the estimated useful lives of the assets as follows: Computer and lab equipment 3 to 5 years Computer software 3 years Furniture and fixtures 3 to 7 years Leasehold improvements Shorter of remaining lease term or estimated useful lives of the assets Costs of maintenance and repairs that do not improve or extend the lives of the respective assets are expensed as incurred. Upon retirement or sale, the cost and related accumulated depreciation are removed from the consolidated balance sheets and the resulting gain or loss is reflected in operating expenses. Intangible Assets Definite long-lived intangible assets consist of software, intellectual property and design win assets for the Company’s Wi-Fi solutions which are recorded based on the total contractual price. Such assets are amortized over its contractual lives and are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If it is determined that such assets are not recoverable, an impairment charge is recognized for the amount by which the carrying amount of such assets exceeds their fair values. There was no impairment of definite long-lived intangible assets for the periods presented. As of December 30, 2018 , the Company’s definite long-lived intangible assets amounted to approximately $5.1 million , net of accumulated amortization of $1.5 million . Impairment of Long-Lived Assets The Company evaluates its long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. When the sum of the undiscounted future net cash flows expected to result from the use of the asset or asset group and its eventual disposition is less than its carrying amount, an impairment loss would be measured based on the discounted cash flows compared to the carrying amount attributable to the asset group. No impairment loss has been recognized for the periods presented. Warranty The Company provides 12 -month warranty coverage on all of its Wi-Fi solutions. The warranty provides for replacement of the associated Wi-Fi solutions during the warranty period. The Company establishes a liability for estimated warranty costs at the time revenue is recognized. The warranty obligation is affected by historical failure rates and associated replacement costs. The warranty liability is included in accrued liabilities and other current liabilities on the consolidated balance sheets. The warranty liability and activity for the periods presented were immaterial. Income Taxes The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. The Company recognizes future tax benefits, measured by enacted tax rates attributable to deductible temporary differences between financial statements and income tax bases of assets and liabilities, and net operating loss carry-forwards to the extent that realization of such benefits is more likely than not. The Company records a liability for the difference between the benefit recognized and measured pursuant to the accounting guidance on accounting for uncertain tax positions and the tax position taken or expected to be taken on the Company’s tax return. To the extent that the assessment of such tax positions changes, the change in estimate is recorded in the period in which the determination is made. The Company establishes these liabilities based on estimates of whether, and the extent to which, additional taxes will be due. These liabilities are established when the Company believes that certain positions might be challenged despite the Company’s belief that the tax return positions are fully supportable. The liabilities are adjusted in light of changing facts and circumstances, such as the outcome of tax audits. Revenue Recognition The Company derives its revenue primarily from the sale of Wi-Fi solutions, net of accruals for estimated sales returns and rebates. The Company adopted Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers (Topic 606) on January 1, 2018 which resulted in a change to its’ revenue policy relating to customer rebate arrangements. Revenue is recognized when control of the promised goods or services is transferred to customers, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those goods or services. The Company adopted Accounting Standard Codification (“ASC”) Topic 606 (“ASC Topic 606”) as of January 1, 2018 using the modified retrospective transition method. Based on the evaluation of its current contracts and revenue streams under the new standard, the Company identified a change in accounting relating to customer rebate arrangements. Under the new standard, the Company is required to account for customer rebate arrangements as variable consideration which requires an estimate of the variable consideration to be made when revenue is recognized. In order to estimate this amount, the Company used historical data to determine an estimate of breakage which was applied to the amount of customer rebate due under its contractual arrangements. The cumulative effect upon adoption of ASC Topic 606 was not material and did not have a material impact on the Company’s consolidated financial position or results of operations. The impact of the estimate of breakage for the year ended December 30, 2018 was approximately $1.0 million , which was recorded as a result of applying the new revenue standard and is not considered material to revenue or any other affected financial statement line items. The Company’s sales arrangements with distributors do not allow for rights of return or price protection on unsold Wi-Fi solutions and its policy is to classify shipping and handling costs, net of costs charged to customers, as cost of revenue. Prior to the adoption of ASC Topic 606, the Company accounted for rebates to end-user customers based on the maximum amount of rebate contractually due under the terms of the arrangement. Claims for customer rebates were charged to the customer rebate accrual when received and approved. Accrued customer rebates were released to revenue only at such time the rebate liability had been extinguished or was considered remote. During the fourth quarter of fiscal 2017, the Company undertook a process to confirm accrued customer rebate balances and obtain confirmation, where possible, from customers of amounts outstanding under customer rebate programs. This confirmation process provided new evidence that the probability of certain customer rebate liabilities being claimed was remote and accordingly the related accrual was reversed and recorded as revenue. The total amount of customer rebate accrual reversed and recorded in revenue during the fourth quarter of fiscal 2017 amounted to approximately $2.0 million . Deferred Revenue Deferred revenue is comprised of billings or payments received in advance of meeting revenue recognition criteria. Research and Development Expenses All costs related to the research and development of the Company’s Wi-Fi solutions are expensed as incurred. Research and development (“R&D”) expense consists primarily of personnel costs for the Company’s R&D activities. R&D expense also includes costs associated with the design and development of the Company’s Wi-Fi solutions, such as mask sets, prototype wafers, prototype engineering boards, software and computer-aided design software licenses, intellectual property licenses, reference design development, development testing and evaluation, depreciation and amortization expense, and allocated administrative costs. Operating Leases The Company recognizes rent expense on a straight-line basis over the non-cancellable term of the operating lease. The difference between rent expense and rent paid is recorded as deferred rent in accrued liabilities and other current liabilities on the consolidated balance sheets. Advertising and Promotion Costs Expenses related to advertising and promotion of products are charged to sales and marketing expense as incurred. The Company incurred immaterial advertising or promotion expenses in the years ended December 30, 2018 , December 31, 2017 and January 1, 2017 , respectively. Stock-Based Compensation The Company measures and recognizes compensation expense for all stock-based awards made to employees, directors and non-employees, based on estimated fair values recognized using the straight-line method over the requisite service period. On January 1, 2017, the Company adopted FASB ASU 2016-09, Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting . Under this guidance, the Company elected the option to no longer apply a forfeiture rate to the stock-based compensation expense, but to record forfeitures when they occur, and, as a result, under the modified retrospective method of adoption the Company recorded an immaterial cumulative effect adjustment of $54,000 to the opening accumulated deficit on January 2, 2017. The fair value of options to purchase common stock granted to employees is estimated on the grant date using the Black-Scholes option valuation model. The calculation of stock-based compensation expense requires that the Company make assumptions and judgments about the variables used in the Black-Scholes model, including the expected term, expected volatility of the underlying common stock and risk-free interest rate. The fair value for restricted stock awards is measured based on the closing market price of our common stock on the date of grant. Net Income (Loss) per Share Basic net income (loss) per share is calculated by dividing the net income (loss) by the weighted-average number of shares of common stock outstanding during the period, without consideration for potentially dilutive securities. Diluted net loss per share is computed by dividing the net loss by the weighted-average number of shares of common stock, without consideration for potentially dilutive securities as the inclusion of such securities would be anti-dilutive. For purposes of the diluted net loss per share calculation, unvested stock awards, warrants, convertible preferred stock and unvested employee stock purchase plan awards are considered to be potentially dilutive securities. Diluted net income per share is calculated by dividing the net income by the weighted-average number of shares of common stock and potentially dilutive securities outstanding for the period. Basic and diluted net loss per share is presented in conformity with the two-class method required for participating securities as the convertible preferred stock is considered a participating security. In addition, the Company considers shares issued upon the early exercise of non-vested warrants to purchase common stock to be participating securities, as the holders of these shares have a non-forfeitable right to dividends. In accordance with the two-class method, earnings allocated to these participating securities and the related number of outstanding shares of the participating securities, which include contractual participation rights in undistributed earnings, have been excluded from the computation of basic and diluted net loss per share attributable to common stockholders. The Company’s participating securities do not have a contractual obligation to share in the Company’s losses. As such, the net loss was attributed entirely to common stockholders. Reclassifications Reclassifications of certain prior period amounts in the consolidated financial statements have been made to conform to the current year presentation.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	12 Months Ended
	Dec. 30, 2018
Accounting Policies [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements On February 14, 2018, the FASB released ASU 2018-02, Income Statement – Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income. The guidance allows a company to elect to reclassify from accumulated other comprehensive income (“AOCI”) to retained earnings the stranded tax effects from the adoption of the newly enacted federal corporate tax rate as a result of the 2017 Tax Cuts and Jobs Act (the “Tax Act”). The amount of the reclassification is calculated as the difference between the amount initially charged to other comprehensive income at the time of the previously enacted tax rate that remains in AOCI and the amount that would have been charged using the newly enacted tax rate, excluding any valuation allowance previously charged to income. ASU 2018-02 is effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years, with early adoption permitted. The Company early-adopted ASU 2018-02 during the third quarter of fiscal 2018 with no material impact to our consolidated financial statements as a result of this adoption. In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities . The new standard is intended to improve and simplify accounting rules around hedge accounting. The new standard refines and expands hedge accounting for both financial (e.g., foreign currency) and commodity risks. Its provisions create more transparency around how economic results are presented, both on the face of the financial statements and in the footnotes, for investors and analysts. The new standard takes effect for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. Early adoption is permitted in any interim period or fiscal years before the effective date of the standard. The Company early-adopted ASU 2017-12 during the second quarter of fiscal 2018 when it commenced its hedging activities with no material impact to our consolidated financial statements as a result of this adoption. Refer to Note 6 to the consolidated financial statements, Derivative Instruments , for further details. In October 2016, the FASB issued ASU No. 2016-16, Income Taxes - Intra-Entity Transfers of Assets Other Than Inventory , which requires entities to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. The standard is effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. Early adoption is permitted as of the beginning of a fiscal year. The new standard must be adopted using a modified retrospective transition method which is a cumulative-effective adjustment to retained earnings as of the beginning of the first effective reporting period. The adoption of this standard has no impact on the Company’s consolidated financial position and results of operations. In February 2016, the FASB issued ASU 2016-02, Leases (“ASC 842”), which sets out the principles for the recognition, measurement, presentation and disclosure of leases for both parties to a contract (i.e., lessees and lessors). The new standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification will determine whether lease expense is recognized based on an effective interest method or on a straight-line basis over the term of the lease, respectively. A lessee is also required to record a right-of-use asset and a lease liability for all leases with a term of greater than twelve months regardless of their classification. Leases with a term of twelve months or less will be accounted for similar to existing guidance for operating leases today. ASC 842 supersedes the previous leases standard, ASC 840 Leases . The standard is effective for the Company as of the first quarter of fiscal 2019. The Company will elect an optional transition method to account for the impact of the adoption with a cumulative-effect adjustment in the period of adoption and will not restate prior periods. It further expects to elect certain practical expedients permitted under the transition guidance and has substantially completed its evaluation of the effect that the adoption of this ASU will have on its financial statements. The Company believes that substantially all of its operating lease commitments will be subject to the new standard and in connection with the adoption of ASC 842, it expects to recognize additional right-of-use assets and operating lease liabilities based on the outstanding lease commitments as of December 30, 2018 and as disclosed in Note 7 to the consolidated financial statements, Commitments and Contingencies - Leases. In accordance with the guidance under ASC 842 and upon adoption, the additional right-of-use assets that will be capitalized and corresponding operating lease liabilities will be recorded at its net present value using an appropriate discount rate.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 30, 2018
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The following table summarizes the Company’s computation of basic and diluted net loss per share: Years Ended December 30, December 31, January 1, (in thousands, except per share data) Net income (loss) $ 3,083 $ 34,412 $ (1,895 ) Weighted-average shares outstanding - basic 36,744 34,259 6,385 Dilutive effect of stock options, ESPP and RSUs 2,919 4,225 — Weighted average shares outstanding - diluted 39,663 38,484 6,385 Net income (loss) per share: Basic $ 0.08 $ 1.00 $ (0.30 ) Diluted $ 0.08 $ 0.89 $ (0.30 ) The following potentially dilutive securities outstanding at the end of the periods have been excluded from the computation of diluted shares outstanding as the effect would have been anti-dilutive: Years Ended December 30, 2018 December 31, 2017 January 1, (in thousands) Warrants to purchase common stock — — 477 Shares available for ESPP 24 — 224 Restricted Stock Units (RSUs) 40 1,095 7 Options to purchase common stock 1,311 857 6,474 Total 1,375 1,952 7,182

Balance Sheets Components

Balance Sheets Components	12 Months Ended
	Dec. 30, 2018
Balance Sheets Components [Abstract]
Balance Sheets Components	Balance Sheets Components Marketable Securities Marketable securities at December 30, 2018 consisted of the following: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) Corporate debt securities $ 85,353 $ 24 $ (242 ) $ 85,135 Government debt securities 12,141 2 (10 ) 12,133 $ 97,494 $ 26 $ (252 ) $ 97,268 The contractual maturities of marketable securities as of December 30, 2018 were as follows: Amortized Cost Fair Value (in thousands) Due in one year or less $ 80,041 $ 79,840 Due after one year to five years 17,453 17,428 $ 97,494 $ 97,268 Marketable securities as of December 31, 2017 consisted of the following: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) Corporate debt securities $ 83,570 $ 7 $ (250 ) $ 83,327 Government debt securities 10,889 — (21 ) 10,868 $ 94,459 $ 7 $ (271 ) $ 94,195 The contractual maturities of marketable securities as of December 31, 2017 were as follows: Amortized Cost Fair Value (in thousands) Due in one year or less $ 49,201 $ 49,144 Due after one year to five years 45,258 45,051 $ 94,459 $ 94,195 Property and equipment, net consisted of the following: December 30, December 31, (in thousands) Computer and lab equipment $ 17,858 $ 14,295 Computer software 1,047 795 Furniture and fixtures 1,739 1,589 Leasehold improvements 4,579 3,977 Sub-total 25,223 20,656 Accumulated depreciation and amortization (11,532 ) (8,145 ) Property and equipment, net 13,691 12,511 Depreciation and amortization expense related to property and equipment was $3.6 million , $2.4 million and $1.3 million , for the years ended December 30, 2018 , December 31, 2017 and January 1, 2017 , respectively. Inventory Inventory consisted of the following: December 30, December 31, (in thousands) Raw materials $ 9,069 $ 5,812 Work in progress 1,093 1,069 Finished goods 10,056 5,781 $ 20,218 $ 12,662 Accrued Liabilities and Other Current Liabilities Accrued liabilities and other current liabilities consisted of the following: December 30, December 31, (in thousands) Accrued customer rebates $ 10,705 $ 8,710 Accrued payroll and related benefits 6,424 3,411 Accrued expenses 3,004 4,507 Accrual for inventory purchases 1,214 2,124 ESPP employee contributions 1,043 706 Other 3,556 1,607 $ 25,946 $ 21,065

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Company determines fair value measurements used in its consolidated financial statements based upon the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The fair value hierarchy distinguishes between (i) market participant assumptions developed based on market data obtained from independent sources (observable inputs) and (ii) an entity’s own assumptions about market participant assumptions developed based on the best information available in the circumstances (unobservable inputs). The fair value hierarchy consists of three broad levels, which gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3). The three levels of the fair value hierarchy are described below: Level 1 Valuations based on quoted prices in active markets for identical assets or liabilities that the entity has the ability to access. Level 2 Valuations based on quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable data for substantially the full term of the assets or liabilities. Level 3 Valuations based on inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. The Company obtains the fair value of its Level 1 investments in money market funds, at the expected market price. These investments are expected to maintain a net asset value of $1 per share. The Company determines the fair value of its Level 2 financial instruments from third-party asset managers, custodian banks, and the accounting service providers. The Company classifies financial instruments in Level 3 of the fair value hierarchy when there is reliance on at least one significant unobservable input to the valuation model. In addition to these unobservable inputs, the valuation models for Level 3 financial instruments typically also rely on a number of inputs that are readily observable, either directly or indirectly. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the asset or liability. There were no assets or liabilities in Level 3 of the fair value hierarchy and there were no transfers between Level 1 and Level 2 categories during the year ended any of the periods presented. The Company utilizes the market approach to measure the fair value of our fixed income securities. The market approach is a valuation technique that uses prices and other relevant information generated by market transactions involving identical or comparable assets or liabilities. The fair value of our fixed income securities is obtained using readily-available market prices from a variety of industry standard data providers, large financial institutions and other third-party sources for the identical underlying securities. Assets and Liabilities Measured at Fair Value on a Recurring Basis As of December 30, 2018 and December 31, 2017 respectively, the Company measures and reports certain assets at fair value on a recurring basis as shown below except for cash held at banks that are measured at historical cost and which are therefore not included in the tables below. Fair Value as of December 30, 2018 Level 1 Level 2 Level 3 Total Assets: (in thousands) Cash equivalents: Money market funds $ 3,170 $ — $ — $ 3,170 Commercial paper — 2,044 — 2,044 Total cash equivalents 3,170 2,044 — 5,214 Marketable Securities: — Corporate debt securities — 85,136 — 85,136 Government debt securities — 12,132 — 12,132 Total marketable securities — 97,268 — 97,268 Total cash equivalents and marketable securities $ 3,170 $ 99,312 $ — $ 102,482 Fair Value as of December 31, 2017 Level 1 Level 2 Level 3 Total Assets: (in thousands) Cash equivalents: Money market funds $ 4,398 $ — $ — $ 4,398 Corporate debt securities — 2,000 — 2,000 Total cash equivalents 4,398 2,000 — 6,398 Marketable Securities: — Corporate debt securities — 83,329 — 83,329 Government debt securities — 10,866 — 10,866 Total marketable securities — 94,195 — 94,195 Total cash equivalents and marketable securities $ 4,398 $ 96,195 $ — $ 100,593 The Level 1 assets consist of money market funds. The Level 2 assets consist of available-for-sale investment portfolio, which are valued utilizing a market approach. Foreign currency derivative forward contracts are measured at fair value based on market-based observable inputs including currency exchange spot and forward rates, interest rates, and credit-risk spreads, and are classified at Level 2 of the fair value hierarchy. Total notional and net fair values for foreign exchange derivative contracts designated as hedging instruments as of December 30, 2018 were as follows: Derivative Assets* Derivative Liabilities* Notional Amount Fair Value Notional Amount Fair Value (in thousands) Current assets $ 376 $ 3 Current liabilities $ 18,386 $ 908 Non-current assets** 2,630 28 Non-current liabilities** 3,050 82 Total foreign exchange contracts $ 3,006 $ 31 Total foreign exchange contracts $ 21,436 $ 990 * The Company recorded a net derivative liability of approximately $1.0 million as of December 30, 2018. There were no derivative assets or liabilities recorded in fiscal 2017. ** Non-current derivative assets and liabilities were discounted at the prevailing risk-free interest rate. Common Stock Warrants During the year ended December 30, 2018 , the remaining 83,006 common stock warrants of those originally issued in September 2015 were exercised at $2.50 per share. There were no outstanding common stock warrants as of December 30, 2018 As of December 31, 2017 , warrants issued and outstanding were as follows: Date of Issuance Number of Warrants Exercise Price Expiration Date Common stock warrants September 2015 83,006 $ 2.50 February 2019

Derivative Instruments

Derivative Instruments	12 Months Ended
	Dec. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments The Company uses foreign currency forward contracts to reduce the earnings impact that exchange rate fluctuations have on operating expenses denominated in currencies other than the U.S. dollar. For accounting purposes, foreign currency forward contracts are designated as hedging instruments and, accordingly, the Company will record the fair value of the effective portion of these contracts as of the end of its’ reporting period in its’ consolidated balance sheets (as an asset or a liability) with changes in fair value recorded within “ Accumulated other comprehensive loss ” under “Total stockholders’ equity”. The fair values of the derivative financial instruments are combined together on the balance sheet whenever there is a master netting arrangement in place. The changes in fair value will remain in “ Accumulated other comprehensive loss ” until the costs are recognized, at which time the Company will reclassify the cumulative change of fair value relating to the hedges proportionately into the respective line items on the condensed consolidated income statements. Any changes in fair value of the ineffective portion of the forward contracts will be recognized immediately in the Company’s consolidated income statement under “ Other income (expense), net ”. In concurrence with the implementation of its hedging program, the Company early-adopted the provisions of ASU 2017-12 as of the beginning of the second quarter of fiscal 2018 on a prospective basis. The early-adoption of ASU 2017-12 did not result in any adjustment to the Company’s consolidated financial statements as of the beginning of the second quarter of fiscal 2018 as the Company did not enter into any hedge accounting activities in prior reporting periods. The effects of derivative instruments and hedging activities on the consolidated statement of operations and its effect on the consolidated statement of comprehensive loss from changes in fair value for the year ended December 30, 2018 was as follows: Location and Amount of Loss Recognized for Hedging Activities: Consolidated Statement of Operations Consolidated Statement of Comprehensive Income (Loss)- (pre-tax) Research and Development Sales and Marketing General and Administrative Total (in thousands) Total expense from foreign currency hedging $ 414 $ 102 $ 27 $ 543 $ (959 ) Effects of foreign currency cashflow hedging: Loss reclassified from consolidated statement of comprehensive Income (loss) $ (414 ) $ (102 ) $ (27 ) $ (543 ) $ 543 Loss recognized in consolidated statement of comprehensive Income (loss) $ — $ — $ — $ — $ (1,502 ) The Company did not enter into any hedging activities in fiscal 2017.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Leases The Company conducts its operations using leased office facilities in various locations. The following is a schedule of future minimum lease payments under operating leases as of December 30, 2018 (in thousands): 2019 $ 2,862 2020 2,333 2021 1,899 2022 1,923 2023 1,809 2024 and beyond 318 Total minimum lease payments $ 11,144 The Company leases office space under arrangements expiring through 2026. Rent expense for the years ended December 30, 2018 , December 31, 2017 and January 1, 2017 was $2.9 million , $1.9 million and $1.2 million , respectively. Purchase Commitments The Company has purchase obligations of $11.4 million that are based on outstanding purchase orders as of December 30, 2018 , related to the fabrication of certain wafers for which production has started. These purchase orders are cancellable at any time, provided that the Company is required to pay all costs incurred through the cancellation date. Historically, the Company has rarely canceled these agreements once production has started. The Company did not otherwise have any outstanding non-cancellable purchase obligations as of December 30, 2018 . Indemnification In connection with the sale of its semiconductor products, the Company executes standard software license agreements allowing customers to use its firmware. Under the indemnification clauses of these license agreements, the Company agrees to defend the licensee against third-party claims asserting infringement by the Company’s products of certain intellectual property rights, which may include patents, copyrights, trademarks or trade secrets, and to pay any judgments entered on such claims against the licensee, subject to certain restrictions and limitations. The Company has never incurred significant expense defending its licensees against third-party claims. Further, the Company has never incurred significant expense under its standard product or services performance warranties. As a result, the Company believes the estimated fair value of these agreements is minimal. Accordingly, the Company has no liabilities recorded for these agreements at December 30, 2018 . Commitments In April 2012, an agreement was entered into with Joint Stock Company “RUSNANO” (“RUSNANO”) (formerly Open Joint Stock Company “RUSNANO”), which required the Company to form a wholly-owned subsidiary in the Russian Federation and to provide funding to the subsidiary in the three years following April 16, 2012. This wholly-owned subsidiary performs research and development activities for the Company. Funding means cash transfers to the subsidiary for equity investments, reimbursements of subsidiary operating expenses and Company expenses related to the subsidiary. RUSNANO also requires participation in subsidiary financial decisions. In July 2014, the Company entered into an amended and restated letter agreement with RUSNANO pursuant to which the Company agreed, among other matters, to operate and fund its Russian operations in an aggregate amount of $13.0 million over six annual periods beginning on December 31, 2014. The annual funding requirements in period one to period six are $2.2 million , $1.7 million , $2.0 million , $2.2 million , $2.4 million , and $2.5 million , respectively. In the event that the Company fails to meet its funding obligations for any period, it will be required to pay RUSNANO a penalty fee of 10% on 80% of the difference between the funding obligation and the actual funding for that period, subject to a cure period of one calendar quarter after the applicable period funding deadline. As of December 30, 2018 , the Company had met the minimum funding requirements and no penalty had been incurred. As of December 30, 2018 , the Company’s non-cancellable obligations for its definite long-lived intangible assets which are comprised of software licenses were approximately $2.6 million , of which $1.5 million and $1.1 million are due payable in fiscal 2019 and fiscal 2020, respectively. In addition, as of December 30, 2018 , the Company also has a non-cancellable commitment with a vendor to purchase additional intellectual property licenses up to $2.5 million upon the successful integration of the vendor’s existing software licenses with the Company’s products. Design Win Commitments In order to further promote its Wi-Fi solutions and secure additional design wins with service providers (“SPs”), the Company enters into arrangements with some of its OEMs and ODMs to incentivize the promotion of its design win solutions with SPs. Once a design win is secured through this arrangement, the Company is obligated to compensate the OEM or ODM a success fee. The resulting liability is expected to be settled through the shipment of its Wi-Fi chips. As of December 30, 2018 , the Company had open commitments to its OEMs and ODMs under these arrangements amounting to $4.3 million . There is no guarantee that the Company will secure some or all of these design wins (including the time frame when such design wins may be realized) in future reporting periods. Legal Matters From time to time, the Company is a party to litigation and subject to claims incident to the ordinary course of business, including intellectual property claims, labor and employment claims, breach of contract claims, and other matters. Significant judgment is required when we assess the likelihood of any adverse judgments or outcomes to a potential claim or legal proceeding, as well as potential ranges of probable losses, and when the outcomes of the claims or proceedings are probable and reasonably estimable. Because of uncertainties related to these matters, we base our estimates on the information available at the time. As additional information becomes available, we reassess the potential liability related to pending claims and litigation, and may revise our estimates. Any revisions in the estimates of potential liabilities could have a material impact on the Company’s results of operations, financial position, and cash flows.

Long-term Debt

Long-term Debt	12 Months Ended
	Dec. 30, 2018
Debt Disclosure [Abstract]
Long-term Debt	Long-term Debt Loan and Security Agreement The Company’s Amended and Restated Loan and Security Agreement with Silicon Valley Bank (“SVB”) (the “SVB Loan and Security Agreement”) included (i) term loans, (ii) a revolving line of credit, and (iii) a mezzanine loan. The mezzanine loan was canceled upon its expiration in fiscal 2017 and the revolving line of credit expired in May 2018. On December 31, 2017, the Company sought to extinguish its term loans under the SVB Loan and Security Agreement of which approximately $3.9 million (including interest and early termination fees) remained outstanding. The Company reclassified the final $3.9 million payment on December 31, 2017 to “Long-term debt, current portion” in its condensed consolidated balance sheet as of that date. The payment for the extinguishment of the term loans was processed on January 2, 2018.

Stockholders_ Equity

Stockholders’ Equity	12 Months Ended
	Dec. 30, 2018
Equity [Abstract]
Stockholders' Equity	Stockholders’ Equity Common Stock The Company’s Certificate of Incorporation, as amended, authorizes the Company to issue 1,000,000,000 shares of $0.0001 par value common stock. Each share of common stock is entitled to 1 vote. The holders of common stock are also entitled to receive dividends whenever funds are legally available and when and if declared by the board of directors, subject to the prior rights of holders of all classes of preferred stock outstanding. The Company has never declared any dividends. The Company had reserved shares of common stock for issuance, on an as-converted basis, as follows: December 30, 2018 Options issued and outstanding 4,391,548 RSUs issued and outstanding 1,868,659 Shares available for ESPP 1,245,492 Shares available for future stock awards 2,563,564 10,069,263

Stock-based Compensation

Stock-based Compensation	12 Months Ended
	Dec. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-based Compensation	Stock-based Compensation We currently grant equity-based awards under the Company’s 2016 Omnibus Equity Incentive Plan, or the “2016 Plan”, which became effective concurrent with the completion of the Company’s IPO in November 2016. The 2016 Plan allows the Company to grant up to 4,100,000 shares of Company’s common stock with annual increase on the first day of each fiscal year beginning of January 1, 2018, equal to the lesser of (i) 3,400,000 shares, (ii) five percent of the outstanding shares of the Company’s common stock as of the last day of the immediately preceding fiscal year; or (iii) such other amounts as the board of directors may determine. The 2016 Plan provides for the grant of common stock awards, including incentive stock options, non-statutory stock options, stock appreciation rights, restricted stock and restricted stock units, performance units and performance shares to employees, directors, and consultants of the Company. All granted shares that are canceled, forfeited or expired are returned to the 2016 Plan and are available for grant in conjunction with the issuance of new equity awards. Stock options may be granted at an exercise price per share not less than 100% of the fair market value at the date of grant. If a stock option is granted to a 10% stockholder, then the exercise price per share must not be less than 110% of the fair market value per share of common stock on the grant date. Options granted are exercisable over a maximum term of 10 years from the date of grant and generally vest over a period of four years. Total stock-based compensation expense for employees and non-employees recognized in the consolidated statements of operations was as follows: Years Ended December 30, December 31, January 1, (in thousands) Cost of revenue $ 199 $ 165 $ 33 Research and development 9,676 5,616 911 Sales and marketing 2,696 1,763 248 General and administrative 4,718 3,139 1,898 Total stock-based compensation expense $ 17,289 $ 10,683 $ 3,090 The above stock-based compensation expense related to the following equity-based awards: Years Ended December 30, 2018 December 31, 2017 January 1, (in thousands) Stock options $ 4,171 $ 3,539 $ 3,090 RSU awards 11,187 5,368 — ESPP shares 1,931 1,776 — Total stock-based compensation expense $ 17,289 $ 10,683 $ 3,090 Unamortized compensation expense related to unvested stock awards was as follows (in thousands): December 30, 2018 December 31, 2017 Unamortized Expense Average Expected Recognition Period in Years Unamortized Expense Average Expected Recognition Period in Years Stock options $ 7,697 2.2 $ 9,275 2.8 RSU awards 23,206 2.3 16,272 2.7 ESPP shares 1,081 0.5 1,182 0.8 Total unamortized stock-based compensation expense $ 31,984 $ 26,729 Stock Option Activity The table below summarizes stock option activity under the 2016 Plan: Number of Number of Weighted– Weighted– Aggregate Balances at December 27, 2015 78,975 5,062,342 $ 1.77 7.4 $ 11,269 Authorized 6,113,092 — RSUs granted (6,950 ) — Granted (weighted–average fair value of $3.65 per share) (2,064,982 ) 2,064,982 8.99 Exercised — (403,769 ) 2.95 Expired, forfeited or canceled 249,931 (249,930 ) 3.14 Balances at January 1, 2017 4,370,066 6,473,625 3.95 7.4 91,840 Granted (weighted–average fair value of $7.91 per share) (703,283 ) 703,283 19.31 Exercised — (1,756,143 ) 1.86 Expired, forfeited or canceled 145,813 (145,813 ) 8.15 Balances at December 31, 2017 3,812,596 5,274,952 6.59 7.2 35,578 Granted (weighted–average fair value of $5.50 per share) (666,250 ) 666,250 13.06 Exercised — (1,293,541 ) 3.23 Expired, forfeited or canceled 256,113 (256,113 ) 12.55 Balances at December 30, 2018 3,402,459 4,391,548 8.21 6.6 30,148 Options vested and exercisable-December 30, 2018 2,626,213 5.57 5.8 24,411 The aggregate intrinsic value of options exercised was $16.5 million , $29.0 million and $2.6 million for the years ended December 30, 2018 , December 31, 2017 and January 1, 2017 , respectively. Upon the exercise of options, the Company issues new common stock from its authorized shares. Stock Options Granted to Employees and Non-Employee Directors Stock-based compensation expense is based on the grant date fair value. The Company recognizes compensation expense for all stock-based awards on a straight-line basis over the requisite service period of the awards, which is generally the option vesting term of four years. The Company uses the Black-Scholes option valuation model, which requires the use of highly subjective assumptions to determine the fair value of stock-based awards. The assumptions used in the Company’s option-pricing model represent management’s best estimates. These estimates are complex, involve a number of variables, uncertainties and assumptions and the application of management’s judgment. If factors change and different assumptions are used, the Company’s stock-based compensation expense could be materially different in the future. The assumptions and estimates that the Company uses in the Black-Scholes model are as follows: • Fair Value of Common Stock . The Company determines the fair values of the shares of common stock underlying its share–based awards based upon the closing stock price on the date of grant. For all periods prior to the IPO, the fair value of common stock was determined on a periodic basis by the Company’s board of directors, with the assistance of an independent third-party valuation firm. • Risk-Free Interest Rate. The Company bases the risk-free interest rate used in the Black-Scholes valuation model on the implied yield available on U.S. Treasury zero-coupon issues with a term equivalent to that of the expected term of the options for each option group. • Expected Term. The expected term represents the period that the Company’s stock-based awards are expected to be outstanding. Because of the limitations on the sale or transfer of the Company’s common stock as a privately held company (up to November 2016), the Company does not believe its historical exercise pattern is indicative of the pattern it will experience as a publicly traded company. The Company has consequently used the Staff Accounting Bulletin 110, or SAB 110, simplified method to calculate the expected term, which is the average of the contractual term and vesting period. The Company plans to continue to use the SAB 110 simplified method until it has sufficient trading history as a publicly traded company. • Volatility. The Company determines the price volatility based on the historical volatilities of industry peers as it has insufficient trading history for its common stock price. Industry peers consist of several public companies in the semiconductor industry with comparable characteristics, including revenue growth, operating model and working capital requirements. The Company intends to continue to consistently apply this process using the same or a similar peer group of public companies until a sufficient amount of historical information regarding the volatility of its own common stock price becomes available, or unless circumstances change such that the identified peer companies are no longer similar, in which case other suitable peer companies whose common stock prices are publicly available would be utilized in the calculation. • Dividend Yield. The expected dividend assumption is based on the Company’s current expectations about its anticipated dividend policy. To date, the Company has not declared any dividends, and therefore the Company has used an expected dividend yield of zero. On January 1, 2017, the Company adopted FASB ASU 2016-09, Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting . Under this guidance, the Company elected the option to no longer apply a forfeiture rate to the stock-based compensation expense, but to record forfeitures when they occur. The Company will continue to use judgment in evaluating the assumptions related to the Company’s stock-based compensation on a prospective basis. As the Company continues to accumulate additional data, it may have refinements to its estimates, which could materially impact the Company’s future stock-based compensation expense. The following assumptions were used to calculate the fair value of options granted to employees and non-employee directors during the years indicated: Years Ended December 30, December 31, January 1, Expected term (in years) 6.08 6.0 - 6.1 5.5 - 6.6 Volatility 40% 37% - 39% 39% - 40% Risk-free interest rate 2.4% 1.9% - 2.3% 1.1% - 2.1% Expected dividend — — — Employee Stock Purchase Plan The Company’s 2016 Employee Stock Purchase Plan (the “ESPP”) allows eligible employees to purchase shares of the Company’s common stock at a discount through payroll deductions of up to 20% of their eligible compensation, subject to any plan limitations. The ESPP generally provides for one year offering periods with purchase periods every six months, and at the end of each purchase period, employees are able to purchase shares at 85% of the lower of the fair market value of the Company’s common stock on the first trading day of the purchase period or on the last trading day of the offering period. The Company issued 400,696 and 353,812 shares under the ESPP for the year ended December 30, 2018 and December 31, 2017 , respectively. Shares authorized for future purchase under the ESPP were 1,245,492 at December 30, 2018 . Compensation expense is calculated using the fair value of the employees' purchase rights under the Black-Scholes model. The following assumptions were used in estimating the fair value of employees' purchase rights under the ESPP: Years Ended December 30, December 31, Contractual term remaining (in years) 0.5 - 1.0 0.5 - 1.0 Volatility 31% - 57% 49% - 66% Risk-free interest rate 2.1% - 2.7% 1.4 % - 1.6% Expected dividend — — Restricted Stock Unit (“RSU”) Awards The Company grants RSUs to employees under the 2016 Plan and which typically vests ratably over a three to four year period, and are converted into shares of the Company’s common stock upon vesting on a one-for-one basis subject to the employee’s continued service to the Company over that period. The fair value of RSUs is determined using the fair value of the Company’s common stock on the date of the grant. Compensation expense is recognized on a straight-line basis over the requisite service period of each grant. Each RSU award granted from the 2016 Plan will reduce the number of shares available for issuance under the 2016 Plan by one share. The table below summarizes RSU activity under the 2016 Plan: Number of Weighted– Aggregate Balances at January 1, 2017 6,950 3.9 $ 126 Granted (weighted–average fair value of $17.72 per share) 1,276,940 Vested (125,818 ) Forfeited or canceled (57,545 ) Balances at December 31, 2017 1,100,527 Granted (weighted–average fair value of $14.93 per share) 1,541,549 Vested (565,618 ) Forfeited or canceled (207,799 ) Balances at December 30, 2018 1,868,659 Outstanding and expected to vest at December 30, 2018 1,868,659 1.2 $ 26,423

Income Taxes

Income Taxes	12 Months Ended
	Dec. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The components of loss before income taxes were as follows: Years Ended December 30, December 31, January 1, (in thousands) United States $ 3,001 $ 33,451 $ 16,535 Foreign 1,048 (33,981 ) (18,063 ) $ 4,049 $ (530 ) $ (1,528 ) The components of the benefit (provision) for income taxes were as follows: Years Ended December 30, December 31, January 1, (in thousands) Federal $ — $ 290 $ (266 ) State (7 ) (16 ) (1 ) Foreign (960 ) (668 ) (132 ) Total current provision for income taxes (967 ) (394 ) (399 ) Federal (14 ) 35,303 — State (2 ) 65 — Foreign 17 (32 ) 32 Total deferred provision 1 35,336 32 $ (966 ) $ 34,942 $ (367 ) The material components of the deferred tax assets were as follows: December 30, December 31, (in thousands) Deferred tax assets: Accrual, reserve and other $ 1,578 $ 1,471 Depreciation and amortization (1,576 ) (1,625 ) Net operating loss and credits carry forwards 49,059 48,401 Stock based compensation 1,881 1,645 Other 252 64 Total gross deferred tax assets 51,194 49,956 Valuation allowance (15,643 ) (14,534 ) Total net deferred tax assets $ 35,551 $ 35,422 A reconciliation of the Company’s effective tax rate to the statutory U.S. federal rate is as follows: Years Ended December 30, December 31, January 1, US Federal Rate 21.0 % 34.0 % 34.0 % State income taxes, net of federal benefit (26.2 ) 867.1 — Difference between statutory rate and foreign effective tax rate 18.5 (2,285.7 ) (437.8 ) Other permanent Items 5.5 (52.3 ) (125.2 ) Stock based compensation (36.5 ) 1,650.1 (29.2 ) Research and development credits (77.3 ) 610.3 102.2 Change in valuation allowance 27.4 8,988.6 477.6 Foreign Income 8.8 (96.1 ) (75.8 ) Foreign Tax Credit — — 30.7 True up 25.5 — — Uncertain tax position 57.2 — — Federal Rate Change — (3,128.1 ) — 23.9 % 6,587.9 % (23.5 )% On December 22, 2017, the U.S. government enacted comprehensive tax legislation commonly referred to as the Tax Act. The Tax Act makes broad and complex changes to the U.S. tax federal and state tax laws that affected 2017, the current year and onwards, including, but not limited to, a reduction of the U.S. federal corporate tax rate from as high as 35% to 21%, a general elimination of U.S. federal income taxes on dividends from foreign subsidiaries, net operating loss deduction limitations, and 100% disallowance of entertainment expense. The Tax Act adds new provisions relating to “foreign derived intangible income” (“FDII”) and “global intangible low-taxed income” (“GILTI”). The Company has completed an analysis for FDII and GILTI and due to the results of the Company, there is currently an immaterial impact on the provision. In addition, the Company’s GILTI policy election is to treat GILTI as a period cost if and when incurred and does not plan on calculating the deferred impact of GILTI. On December 22, 2017, the SEC staff issued Staff Accounting Bulletin No. 118 (“SAB 118”) which provides guidance on accounting for the tax effects of the Tax Act. SAB 118 provides a measurement period that should not extend beyond one year from the Tax Act enactment date for companies to complete the accounting under ASC 740, Income Taxes (“ASC 740”) for the year ended December 31, 2017. In accordance with SAB 118, a company must reflect the income tax effects of those aspects of the Tax Act for which the accounting under ASC 740 is complete. The Company has finished their analysis as of the measurement period closing of December 22,2018 after application of law changes were reviewed by the Company. There were no subsequent adjustments as the conclusions have remained the same. As of December 30, 2018 , based on the available objective evidence, management believes it is more likely than not that the net deferred tax assets will be realized for federal and state purposes. Accordingly, in 2017, management has released its valuation allowance against its federal and states, excluding California, net deferred tax assets. With respect to California, the Company is generating more credits than its tax liability on an annual basis. Management believes it is more likely than not that the net deferred tax assets will not be realized for California purposes and thus maintained its valuation allowance against its California net deferred tax assets. The Company's operation in Australia generates more credits than its tax liability. As such, management believes it is more likely than not that the net deferred tax assets will not be realized for Australia purposes. Accordingly, management has a full valuation allowance against its Australian net deferred tax assets. Management’s evaluation as described above is made on currently available evidence and which is subject to change if additional information becomes known or changes due to facts and circumstances. At December 30, 2018 and December 31, 2017 , the Company had federal net operating loss carryforwards of approximately $117.0 million and $120.2 million , respectively, that expire beginning in 2028, and domestic state net operating loss carryforwards of approximately $92.4 million and $104.6 million , respectively, that will begin to expire in 2028. At December 30, 2018 and December 31, 2017 , the Company also had Federal research and development credit carryforwards of approximately $14.9 million and $10.6 million , respectively, that begin to expire in 2026, and domestic state research and development credit carryforwards of approximately $13.5 million and $11.0 million , respectively, that do not expire. Under Internal Revenue Code Section 382, our ability to utilize NOL carry-forwards or other tax attributes such as research tax credits, in any taxable year may be limited if we experience, or have experienced, an "ownership change." A Section 382 "ownership change" generally occurs if one or more stockholders or groups of stockholders, who own at least 5% of our stock, increase their ownership by more than 50 percentage points over their lowest ownership percentage within a rolling three-year period. Similar rules may apply under state tax laws. During the year ended and December 30, 2018 , the liability for uncertain tax positions less accrued interest and penalties increased from $5.3 million for the prior year to $8.3 million . Of the total $8.3 million of unrecognized tax benefits, $5.6 million represents the amount that if recognized, would favorably affect the effective income tax rate in any future periods. The Company cannot conclude on the range of cash payments that will be made within the next twelve months associated with its uncertain tax positions. A reconciliation of the beginning and ending unrecognized tax benefit amount is as follows: December 30, December 31, January 1, (in thousands) Beginning balance $ 5,318 $ 5,221 $ 4,425 Increases related to current year’s unrecognized tax benefits 3,283 1,569 888 Increases related to prior year’s unrecognized tax benefits 107 68 — Decreases related to prior year’s unrecognized tax benefits (442 ) (1,540 ) (92 ) Ending balance $ 8,266 $ 5,318 $ 5,221 The valuation allowance for deferred tax assets consisted of the following activity for the fiscal years 2018 , 2017 and 2016 : Balance at Beginning of Year Additions Reductions Balance at End of Year Allowance for deferred tax assets (in thousands) Year ended December 30, 2018 $ 14,534 $ 1,109 $ — $ 15,643 Year ended December 31, 2017 62,207 4,260 (51,933 ) 14,534 Year ended January 1, 2017 $ 67,194 $ 705 $ (5,692 ) $ 62,207 The Company records interest and penalties related to unrecognized tax benefits in income tax expense. For the year ended December 30, 2018 and December 31, 2017 , the Company recorded no estimated interest or estimated penalties. The Company and its subsidiaries are subject to taxation in various jurisdictions, including federal, state and foreign. The Company’s federal and state income tax returns are generally not subject to examination by taxing authorities for fiscal years before 2014 for federal purposes and 2013 for state purposes. The exceptions to this are the net operating loss carryovers and R&D credit carryovers. These amounts are subject to audit for a period of three years after utilization for federal purposes and four years after utilization for state purposes. The Company intends to reinvest the earnings of its non-U.S. subsidiaries in those operations. The Company has not provided for foreign withholding taxes on the earnings of foreign subsidiaries because the Company intends to reinvest such earnings offshore indefinitely. It is not practicable to estimate the amount of the deferred tax liability associated with the repatriation of cash due to the complexity of its hypothetical calculation. As of December 30, 2018 , there is approximately $9.7 million of earnings upon which foreign withholding taxes have not been provided.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 30, 2018
Retirement Benefits [Abstract]
Employee Benefit Plans	Employee Benefit Plans Defined Contribution Plan The Company adopted a 401(k) Plan that qualifies as a deferred compensation arrangement under Section 401 of the Internal Revenue Code. Under the 401(k) Plan, participating employees may defer a portion of their pretax earnings not to exceed the maximum amount allowable. The 401(k) Plan permits the Company to make matching contributions and profit sharing contributions to eligible participants. The Company has made matching contributions of $0.5 million and $0.5 million for the years ended December 30, 2018 and December 31, 2017 , respectively.

Segment Information and Operati

Segment Information and Operations by Geographic Area	12 Months Ended
	Dec. 30, 2018
Segment Reporting [Abstract]
Segment Information and Operations by Geographic Area	Segment Information and Operations by Geographic Area The chief operating decision maker for the Company is the Chief Executive Officer. The Chief Executive Officer reviews financial information presented on a consolidated basis for purposes of allocating resources and evaluating financial performance. The Company has one business activity consisting of design, development, and marketing of advanced high-speed wireless communication solutions enabling wireless local area networking, and there are no segment managers who are held accountable for operations, operating results or plans for levels or components below the consolidated level. Accordingly, the Company has determined that it has a single reportable and operating segment structure. The following table sets forth the Company’s revenue by geographic region, based on ship-to destinations (in thousands): Years Ended December 30, 2018 December 31, 2017 January 1, 2017 Amount % of revenue Amount % of revenue Amount % of revenue Asia-Pacific $ 202,342 92 % $ 162,059 92 % $ 114,499 89 % Europe, Middle East and Africa 17,953 8 14,015 8 14,353 11 Americas 165 — 285 — 217 — Total $ 220,460 100 % $ 176,359 100 % $ 129,069 100 % Long-lived assets outside the U.S. are immaterial; therefore, disclosures have been limited to revenue. The following table sets forth revenue by country, based on ship-to destinations, for countries with 10% or more of revenue during any of the periods presented: Years Ended December 30, December 31, January 1, Amount % of revenue Amount % of revenue Amount % of revenue (Dollars in thousands) China $ 123,383 56 % $ 119,821 68 % $ 86,107 66 % Vietnam 56,125 25 — — — — Taiwan 19,050 9 17,780 10 13,752 11 Tunisia 17,334 8 13,410 8 13,755 11 United States 111 — 283 — 291 — Other foreign countries 4,457 2 25,065 14 15,164 12 Total $ 220,460 100 % $ 176,359 100 % $ 129,069 100 %

Related Party transactions

Related Party transactions	12 Months Ended
	Dec. 30, 2018
Related Party Transactions [Abstract]
Related Party transactions	Related Party transactions Purchases from Cadence Design Systems, Inc. Lip-Bu Tan, a member of the Company’s board of directors since June 2015, resigned from the board in accordance with his previously announced intentions, effective June 5, 2018 in connection with the Company’s Annual Meeting of Stockholders. As a result, Mr. Tan ceased to be a related party to the Company during the second quarter of fiscal 2018 which ended on July 1, 2018. Mr. Tan is the President and Chief Executive Officer of Cadence Design Systems, Inc. (“Cadence”), an electronic design automation software and engineering services company. Since 2012, the Company has paid licensing fees for digital and analog layout tools and simulation tools from Cadence in the ordinary course of business. In fiscal 2017, the Company entered into a software license contract with Cadence for the use of various EDA software tools used for its research and development efforts. The Company classified the software licenses as definite long-lived intangible assets in its condensed consolidated balance sheets amounting to approximately $2.4 million as of July 1, 2018, net of accumulated amortization of approximately $0.8 million . Under the terms of this arrangement, the Company amortized fees, in its condensed consolidated statements of operations, of approximately $0.5 million during the six months ended July 1, 2018, and approximately $3.0 million and $1.7 million for the year ended December 31, 2017 and January 1, 2017 , respectively. Agreement with RUSNANO Dmitry Akhanov, formerly a member of the Company’s board of directors, is President and Chief Executive Officer at Rusnano USA, Inc., a U.S. subsidiary of RUSNANO, one of the Company’s investors. In July 2014, the Company entered into an amended and restated letter agreement with RUSNANO in connection with RUSNANO’s investment in convertible promissory notes, which subsequently converted into shares of the Company’s Series G convertible preferred stock. Pursuant to the amended and restated letter agreement, the Company agreed, among other matters, to operate and fund the Company’s Russian operations in an aggregate amount of $13.0 million over six annual periods beginning on December 31, 2014. The annual funding requirements in period one to period six are $2.2 million , $1.7 million , $2.0 million , $2.2 million , $2.4 million , and $2.5 million , respectively. In the event that the Company fails to meet its funding obligations for any period, the Company will be required to pay RUSNANO a penalty fee of 10% on 80% of the difference between the funding obligation and the actual funding for that period, subject to a cure period of one calendar quarter after the applicable period funding deadline. As of December 30, 2018 , the Company had met the minimum funding requirements.

The Company and Summary of Si_2

The Company and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Reporting Calendar	Reporting Calendar The Company prepares financial statements on a 52- or 53-week fiscal year that ends on the Sunday closest to December 31. The fiscal years ended on December 30, 2018 , December 31, 2017 and January 1, 2017 consisted of 52 weeks, 52 weeks and 53 weeks, respectively. Fiscal 2019 consists of 52 weeks ending on December 29, 2019.
Use of Estimates	Use of Estimates Preparation of financial statements in conformity with accounting principles generally accepted in the United States of America, or US GAAP, requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and reported amounts of revenue and expenses during the reporting periods covered by the financial statements and accompanying notes. Among the significant estimates affecting the financial statements are those related to inventories, revenue recognition, stock-based compensation and income taxes. Actual results could differ from those estimates.
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany transactions and balances have been eliminated in consolidation.
Foreign Currency Remeasurement	Foreign Currency Remeasurement The Company and its subsidiaries use the U.S. dollar as the functional currency. Foreign currency assets and liabilities are remeasured into U.S. dollars at the end-of-period exchange rates except for non-monetary assets and liabilities, which are measured at historical exchange rates. Revenue and expenses are remeasured using an average exchange rate for the respective period, except for expenses related to non-monetary assets and liabilities, which are measured at historical exchange rates. Gains or losses from foreign currency remeasurement and transactions are included in “Other income (expense), net”.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash equivalents include liquid short-term investments with original or remaining maturities of three months or less at the date of purchase, readily convertible to known amounts of cash.
Marketable Securities	Marketable Securities Marketable securities consist primarily of highly liquid investments with maturities of greater than 90 days when purchased. We generally classify our marketable securities at the date of acquisition as available-for-sale. These securities are reported at fair value with the related unrealized gains and losses included in " Accumulated other comprehensive loss ", a component of stockholders’ equity, net of tax. Any unrealized losses which are considered to be other-than-temporary impairments are recorded in " Other income (expense), net " in the Consolidated Statements of Operations. Realized gains (losses) on the sale of marketable securities are determined using the specific-identification method and recorded in " Other income (expense), net " in the Consolidated Statements of Operations. All of our available-for-sale investments are subject to a periodic impairment review. We record a charge to earnings when a decline in fair value is significantly below cost basis and judged to be other-than-temporary, or have other indicators of impairments. If the fair value of an available-for-sale investment is less than its amortized cost basis, an other-than-temporary impairment is triggered in circumstances where (1) we intend to sell the instrument, (2) it is more likely than not that we will be required to sell the instrument before recovery of its amortized cost basis or (3) a credit loss exists where we do not expect to recover the entire amortized cost basis of the instrument. If we intend to sell or it is more likely than not that we will be required to sell the available-for-sale investment before recovery of its amortized cost basis, we recognize an other-than temporary impairment charge equal to the entire difference between the investment's amortized cost basis and its fair value.
Derivative Financial Instruments	Derivative Financial Instruments The Company uses derivative instruments to manage its exposure to changes in foreign currency exchange rates from forecasted cash flows associated with the operational expenses of its foreign subsidiaries. Derivative instruments are measured at their fair values and recognized as either assets or liabilities. The Company’s derivative forward contracts are designated as cash-flow hedges and their effectiveness is measured by comparing the cumulative forward-rate changes in the fair value of the hedge contract with the cumulative forward-rate change in the forecasted cash flows of the hedged item.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The carrying amounts of the Company’s financial instruments, which include cash equivalents, accounts receivable, accounts payable and accrued liabilities and other current liabilities, approximate their fair values due to their short maturities. Estimates of fair value of our marketable securities are based on quoted market prices from active markets or third party, market-based pricing sources which we believe to be reliable. Derivative instruments are measured at their fair values and recognized as either assets or liabilities.
Accounts Receivable and Allowances for Doubtful Accounts	Accounts Receivable and Allowances for Doubtful Accounts Accounts receivable are stated at invoice value less estimated allowances for returns and doubtful accounts. The Company continually monitors customer payments and maintains an allowance for estimated losses resulting from its customers’ inability to make required payments. The Company considers factors such as historical experience, credit quality, age of the accounts receivable balances, geographic related risks and economic conditions that may affect a customer’s ability to pay. In cases where there are circumstances that may impair a specific customer’s ability to meet its financial obligations, a specific allowance is recorded against amounts due, which reduces the net recognized receivable to the amount reasonably believed to be collectible.
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist principally of cash and cash equivalents, marketable securities and accounts receivable. We invest our excess cash primarily in banks, money market funds, government debt securities and corporate debt securities. We have established guidelines relative to credit ratings, diversification and maturities that seek to maintain safety and liquidity.
Inventory	Inventory Inventory is stated at the lower of cost to purchase or manufacture the inventory or the market value of such inventory. Cost is determined using the standard cost method which approximates the first-in first-out basis. Market value is determined as the lower of replacement cost or net realizable value. The Company, at least quarterly, assesses the recoverability of all inventories to determine whether adjustments are required to record inventory at the lower of cost or market. Potentially excess and obsolete inventory is written off based on management’s analysis of inventory levels and estimates of future 12-month demand and market conditions. The Company is also entitled to receive rebates from its foundry partner on the purchase of silicon wafers upon achieving certain volume targets. Rebates from the Company’s foundry partner are recorded as a reduction of inventory cost when it is probable and reasonably estimable, and are recognized in cost of revenue as the chipsets made from such silicon wafers are sold to customers.
Prepaid Expenses and Other Current Assets
Property and Equipment	Property and Equipment Property and equipment are stated at cost and depreciated using the straight‑line method over the estimated useful lives of the assets as follows: Computer and lab equipment 3 to 5 years Computer software 3 years Furniture and fixtures 3 to 7 years Leasehold improvements Shorter of remaining lease term or estimated useful lives of the assets Costs of maintenance and repairs that do not improve or extend the lives of the respective assets are expensed as incurred. Upon retirement or sale, the cost and related accumulated depreciation are removed from the consolidated balance sheets and the resulting gain or loss is reflected in operating expenses.
Intangible Assets	Intangible Assets Definite long-lived intangible assets consist of software, intellectual property and design win assets for the Company’s Wi-Fi solutions which are recorded based on the total contractual price. Such assets are amortized over its contractual lives and are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If it is determined that such assets are not recoverable, an impairment charge is recognized for the amount by which the carrying amount of such assets exceeds their fair values.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company evaluates its long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. When the sum of the undiscounted future net cash flows expected to result from the use of the asset or asset group and its eventual disposition is less than its carrying amount, an impairment loss would be measured based on the discounted cash flows compared to the carrying amount attributable to the asset group.
Warranty	Warranty The Company provides 12 -month warranty coverage on all of its Wi-Fi solutions. The warranty provides for replacement of the associated Wi-Fi solutions during the warranty period. The Company establishes a liability for estimated warranty costs at the time revenue is recognized. The warranty obligation is affected by historical failure rates and associated replacement costs. The warranty liability is included in accrued liabilities and other current liabilities on the consolidated balance sheets.
Income Taxes	Income Taxes The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. The Company recognizes future tax benefits, measured by enacted tax rates attributable to deductible temporary differences between financial statements and income tax bases of assets and liabilities, and net operating loss carry-forwards to the extent that realization of such benefits is more likely than not. The Company records a liability for the difference between the benefit recognized and measured pursuant to the accounting guidance on accounting for uncertain tax positions and the tax position taken or expected to be taken on the Company’s tax return. To the extent that the assessment of such tax positions changes, the change in estimate is recorded in the period in which the determination is made. The Company establishes these liabilities based on estimates of whether, and the extent to which, additional taxes will be due. These liabilities are established when the Company believes that certain positions might be challenged despite the Company’s belief that the tax return positions are fully supportable. The liabilities are adjusted in light of changing facts and circumstances, such as the outcome of tax audits.
Revenue Recognition and Deferred Revenue	Revenue Recognition The Company derives its revenue primarily from the sale of Wi-Fi solutions, net of accruals for estimated sales returns and rebates. The Company adopted Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers (Topic 606) on January 1, 2018 which resulted in a change to its’ revenue policy relating to customer rebate arrangements. Revenue is recognized when control of the promised goods or services is transferred to customers, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those goods or services. The Company adopted Accounting Standard Codification (“ASC”) Topic 606 (“ASC Topic 606”) as of January 1, 2018 using the modified retrospective transition method. Based on the evaluation of its current contracts and revenue streams under the new standard, the Company identified a change in accounting relating to customer rebate arrangements. Under the new standard, the Company is required to account for customer rebate arrangements as variable consideration which requires an estimate of the variable consideration to be made when revenue is recognized. In order to estimate this amount, the Company used historical data to determine an estimate of breakage which was applied to the amount of customer rebate due under its contractual arrangements. The cumulative effect upon adoption of ASC Topic 606 was not material and did not have a material impact on the Company’s consolidated financial position or results of operations. The impact of the estimate of breakage for the year ended December 30, 2018 was approximately $1.0 million , which was recorded as a result of applying the new revenue standard and is not considered material to revenue or any other affected financial statement line items. The Company’s sales arrangements with distributors do not allow for rights of return or price protection on unsold Wi-Fi solutions and its policy is to classify shipping and handling costs, net of costs charged to customers, as cost of revenue. Prior to the adoption of ASC Topic 606, the Company accounted for rebates to end-user customers based on the maximum amount of rebate contractually due under the terms of the arrangement. Claims for customer rebates were charged to the customer rebate accrual when received and approved. Accrued customer rebates were released to revenue only at such time the rebate liability had been extinguished or was considered remote. During the fourth quarter of fiscal 2017, the Company undertook a process to confirm accrued customer rebate balances and obtain confirmation, where possible, from customers of amounts outstanding under customer rebate programs. This confirmation process provided new evidence that the probability of certain customer rebate liabilities being claimed was remote and accordingly the related accrual was reversed and recorded as revenue. The total amount of customer rebate accrual reversed and recorded in revenue during the fourth quarter of fiscal 2017 amounted to approximately $2.0 million . Deferred Revenue Deferred revenue is comprised of billings or payments received in advance of meeting revenue recognition criteria.
Research and Development Expense	Research and Development Expenses All costs related to the research and development of the Company’s Wi-Fi solutions are expensed as incurred. Research and development (“R&D”) expense consists primarily of personnel costs for the Company’s R&D activities. R&D expense also includes costs associated with the design and development of the Company’s Wi-Fi solutions, such as mask sets, prototype wafers, prototype engineering boards, software and computer-aided design software licenses, intellectual property licenses, reference design development, development testing and evaluation, depreciation and amortization expense, and allocated administrative costs.
Operating Leases	Operating Leases The Company recognizes rent expense on a straight-line basis over the non-cancellable term of the operating lease. The difference between rent expense and rent paid is recorded as deferred rent in accrued liabilities and other current liabilities on the consolidated balance sheets.
Advertising and Promotion Costs	Advertising and Promotion Costs Expenses related to advertising and promotion of products are charged to sales and marketing expense as incurred.
Stock-based Compensation	Stock-Based Compensation The Company measures and recognizes compensation expense for all stock-based awards made to employees, directors and non-employees, based on estimated fair values recognized using the straight-line method over the requisite service period. On January 1, 2017, the Company adopted FASB ASU 2016-09, Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting . Under this guidance, the Company elected the option to no longer apply a forfeiture rate to the stock-based compensation expense, but to record forfeitures when they occur, and, as a result, under the modified retrospective method of adoption the Company recorded an immaterial cumulative effect adjustment of $54,000 to the opening accumulated deficit on January 2, 2017. The fair value of options to purchase common stock granted to employees is estimated on the grant date using the Black-Scholes option valuation model. The calculation of stock-based compensation expense requires that the Company make assumptions and judgments about the variables used in the Black-Scholes model, including the expected term, expected volatility of the underlying common stock and risk-free interest rate. The fair value for restricted stock awards is measured based on the closing market price of our common stock on the date of grant.
Net Income (Loss) per Share	Net Income (Loss) per Share Basic net income (loss) per share is calculated by dividing the net income (loss) by the weighted-average number of shares of common stock outstanding during the period, without consideration for potentially dilutive securities. Diluted net loss per share is computed by dividing the net loss by the weighted-average number of shares of common stock, without consideration for potentially dilutive securities as the inclusion of such securities would be anti-dilutive. For purposes of the diluted net loss per share calculation, unvested stock awards, warrants, convertible preferred stock and unvested employee stock purchase plan awards are considered to be potentially dilutive securities. Diluted net income per share is calculated by dividing the net income by the weighted-average number of shares of common stock and potentially dilutive securities outstanding for the period. Basic and diluted net loss per share is presented in conformity with the two-class method required for participating securities as the convertible preferred stock is considered a participating security. In addition, the Company considers shares issued upon the early exercise of non-vested warrants to purchase common stock to be participating securities, as the holders of these shares have a non-forfeitable right to dividends. In accordance with the two-class method, earnings allocated to these participating securities and the related number of outstanding shares of the participating securities, which include contractual participation rights in undistributed earnings, have been excluded from the computation of basic and diluted net loss per share attributable to common stockholders. The Company’s participating securities do not have a contractual obligation to share in the Company’s losses. As such, the net loss was attributed entirely to common stockholders.
Reclassifications	Reclassifications Reclassifications of certain prior period amounts in the consolidated financial statements have been made to conform to the current year presentation.
New Accounting Pronouncements	Recent Accounting Pronouncements On February 14, 2018, the FASB released ASU 2018-02, Income Statement – Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income. The guidance allows a company to elect to reclassify from accumulated other comprehensive income (“AOCI”) to retained earnings the stranded tax effects from the adoption of the newly enacted federal corporate tax rate as a result of the 2017 Tax Cuts and Jobs Act (the “Tax Act”). The amount of the reclassification is calculated as the difference between the amount initially charged to other comprehensive income at the time of the previously enacted tax rate that remains in AOCI and the amount that would have been charged using the newly enacted tax rate, excluding any valuation allowance previously charged to income. ASU 2018-02 is effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years, with early adoption permitted. The Company early-adopted ASU 2018-02 during the third quarter of fiscal 2018 with no material impact to our consolidated financial statements as a result of this adoption. In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities . The new standard is intended to improve and simplify accounting rules around hedge accounting. The new standard refines and expands hedge accounting for both financial (e.g., foreign currency) and commodity risks. Its provisions create more transparency around how economic results are presented, both on the face of the financial statements and in the footnotes, for investors and analysts. The new standard takes effect for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. Early adoption is permitted in any interim period or fiscal years before the effective date of the standard. The Company early-adopted ASU 2017-12 during the second quarter of fiscal 2018 when it commenced its hedging activities with no material impact to our consolidated financial statements as a result of this adoption. Refer to Note 6 to the consolidated financial statements, Derivative Instruments , for further details. In October 2016, the FASB issued ASU No. 2016-16, Income Taxes - Intra-Entity Transfers of Assets Other Than Inventory , which requires entities to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. The standard is effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. Early adoption is permitted as of the beginning of a fiscal year. The new standard must be adopted using a modified retrospective transition method which is a cumulative-effective adjustment to retained earnings as of the beginning of the first effective reporting period. The adoption of this standard has no impact on the Company’s consolidated financial position and results of operations. In February 2016, the FASB issued ASU 2016-02, Leases (“ASC 842”), which sets out the principles for the recognition, measurement, presentation and disclosure of leases for both parties to a contract (i.e., lessees and lessors). The new standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification will determine whether lease expense is recognized based on an effective interest method or on a straight-line basis over the term of the lease, respectively. A lessee is also required to record a right-of-use asset and a lease liability for all leases with a term of greater than twelve months regardless of their classification. Leases with a term of twelve months or less will be accounted for similar to existing guidance for operating leases today. ASC 842 supersedes the previous leases standard, ASC 840 Leases . The standard is effective for the Company as of the first quarter of fiscal 2019. The Company will elect an optional transition method to account for the impact of the adoption with a cumulative-effect adjustment in the period of adoption and will not restate prior periods. It further expects to elect certain practical expedients permitted under the transition guidance and has substantially completed its evaluation of the effect that the adoption of this ASU will have on its financial statements. The Company believes that substantially all of its operating lease commitments will be subject to the new standard and in connection with the adoption of ASC 842, it expects to recognize additional right-of-use assets and operating lease liabilities based on the outstanding lease commitments as of December 30, 2018 and as disclosed in Note 7 to the consolidated financial statements, Commitments and Contingencies - Leases. In accordance with the guidance under ASC 842 and upon adoption, the additional right-of-use assets that will be capitalized and corresponding operating lease liabilities will be recorded at its net present value using an appropriate discount rate.
Fair Value Measurement	The Company determines fair value measurements used in its consolidated financial statements based upon the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The fair value hierarchy distinguishes between (i) market participant assumptions developed based on market data obtained from independent sources (observable inputs) and (ii) an entity’s own assumptions about market participant assumptions developed based on the best information available in the circumstances (unobservable inputs). The fair value hierarchy consists of three broad levels, which gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3). The three levels of the fair value hierarchy are described below: Level 1 Valuations based on quoted prices in active markets for identical assets or liabilities that the entity has the ability to access. Level 2 Valuations based on quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable data for substantially the full term of the assets or liabilities. Level 3 Valuations based on inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. The Company obtains the fair value of its Level 1 investments in money market funds, at the expected market price. These investments are expected to maintain a net asset value of $1 per share. The Company determines the fair value of its Level 2 financial instruments from third-party asset managers, custodian banks, and the accounting service providers. The Company classifies financial instruments in Level 3 of the fair value hierarchy when there is reliance on at least one significant unobservable input to the valuation model. In addition to these unobservable inputs, the valuation models for Level 3 financial instruments typically also rely on a number of inputs that are readily observable, either directly or indirectly. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the asset or liability. There were no assets or liabilities in Level 3 of the fair value hierarchy and there were no transfers between Level 1 and Level 2 categories during the year ended any of the periods presented. The Company utilizes the market approach to measure the fair value of our fixed income securities. The market approach is a valuation technique that uses prices and other relevant information generated by market transactions involving identical or comparable assets or liabilities. The fair value of our fixed income securities is obtained using readily-available market prices from a variety of industry standard data providers, large financial institutions and other third-party sources for the identical underlying securities.

The Company and Summary of Si_3

The Company and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedules of Concentration of Risk, by Risk Factor	The following table discloses these customers’ percentage of revenue for the respective periods: Years Ended December 30, December 31, January 1, Customer A 29% 16% 11% B * * 19% C * * 11% * Total customer percentage of revenue was less than 10% . The following table discloses customer balances that accounted for 10% or more of accounts receivable: December 30, December 31, Customer A 36% 31% B 14% * C * 12% D 10% * E 10% 14%
Property, Plant and Equipment Useful Lives	Property and equipment are stated at cost and depreciated using the straight‑line method over the estimated useful lives of the assets as follows: Computer and lab equipment 3 to 5 years Computer software 3 years Furniture and fixtures 3 to 7 years Leasehold improvements Shorter of remaining lease term or estimated useful lives of the assets

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 30, 2018
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The following table summarizes the Company’s computation of basic and diluted net loss per share: Years Ended December 30, December 31, January 1, (in thousands, except per share data) Net income (loss) $ 3,083 $ 34,412 $ (1,895 ) Weighted-average shares outstanding - basic 36,744 34,259 6,385 Dilutive effect of stock options, ESPP and RSUs 2,919 4,225 — Weighted average shares outstanding - diluted 39,663 38,484 6,385 Net income (loss) per share: Basic $ 0.08 $ 1.00 $ (0.30 ) Diluted $ 0.08 $ 0.89 $ (0.30 )
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The following potentially dilutive securities outstanding at the end of the periods have been excluded from the computation of diluted shares outstanding as the effect would have been anti-dilutive: Years Ended December 30, 2018 December 31, 2017 January 1, (in thousands) Warrants to purchase common stock — — 477 Shares available for ESPP 24 — 224 Restricted Stock Units (RSUs) 40 1,095 7 Options to purchase common stock 1,311 857 6,474 Total 1,375 1,952 7,182

Balance Sheets Components (Tabl

Balance Sheets Components (Tables)	12 Months Ended
	Dec. 30, 2018
Balance Sheets Components [Abstract]
Marketable Securities	Marketable securities at December 30, 2018 consisted of the following: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) Corporate debt securities $ 85,353 $ 24 $ (242 ) $ 85,135 Government debt securities 12,141 2 (10 ) 12,133 $ 97,494 $ 26 $ (252 ) $ 97,268 The contractual maturities of marketable securities as of December 30, 2018 were as follows: Amortized Cost Fair Value (in thousands) Due in one year or less $ 80,041 $ 79,840 Due after one year to five years 17,453 17,428 $ 97,494 $ 97,268 Marketable securities as of December 31, 2017 consisted of the following: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) Corporate debt securities $ 83,570 $ 7 $ (250 ) $ 83,327 Government debt securities 10,889 — (21 ) 10,868 $ 94,459 $ 7 $ (271 ) $ 94,195 The contractual maturities of marketable securities as of December 31, 2017 were as follows: Amortized Cost Fair Value (in thousands) Due in one year or less $ 49,201 $ 49,144 Due after one year to five years 45,258 45,051 $ 94,459 $ 94,195
Schedule of Property and Equipment	Property and equipment, net consisted of the following: December 30, December 31, (in thousands) Computer and lab equipment $ 17,858 $ 14,295 Computer software 1,047 795 Furniture and fixtures 1,739 1,589 Leasehold improvements 4,579 3,977 Sub-total 25,223 20,656 Accumulated depreciation and amortization (11,532 ) (8,145 ) Property and equipment, net 13,691 12,511
Schedule of Inventory	Inventory consisted of the following: December 30, December 31, (in thousands) Raw materials $ 9,069 $ 5,812 Work in progress 1,093 1,069 Finished goods 10,056 5,781 $ 20,218 $ 12,662
Other Current Liabilities	Accrued liabilities and other current liabilities consisted of the following: December 30, December 31, (in thousands) Accrued customer rebates $ 10,705 $ 8,710 Accrued payroll and related benefits 6,424 3,411 Accrued expenses 3,004 4,507 Accrual for inventory purchases 1,214 2,124 ESPP employee contributions 1,043 706 Other 3,556 1,607 $ 25,946 $ 21,065
Schedule of Accrued Liabilities	Accrued liabilities and other current liabilities consisted of the following: December 30, December 31, (in thousands) Accrued customer rebates $ 10,705 $ 8,710 Accrued payroll and related benefits 6,424 3,411 Accrued expenses 3,004 4,507 Accrual for inventory purchases 1,214 2,124 ESPP employee contributions 1,043 706 Other 3,556 1,607 $ 25,946 $ 21,065

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value, Assets Measured on Recurring Basis	As of December 30, 2018 and December 31, 2017 respectively, the Company measures and reports certain assets at fair value on a recurring basis as shown below except for cash held at banks that are measured at historical cost and which are therefore not included in the tables below. Fair Value as of December 30, 2018 Level 1 Level 2 Level 3 Total Assets: (in thousands) Cash equivalents: Money market funds $ 3,170 $ — $ — $ 3,170 Commercial paper — 2,044 — 2,044 Total cash equivalents 3,170 2,044 — 5,214 Marketable Securities: — Corporate debt securities — 85,136 — 85,136 Government debt securities — 12,132 — 12,132 Total marketable securities — 97,268 — 97,268 Total cash equivalents and marketable securities $ 3,170 $ 99,312 $ — $ 102,482 Fair Value as of December 31, 2017 Level 1 Level 2 Level 3 Total Assets: (in thousands) Cash equivalents: Money market funds $ 4,398 $ — $ — $ 4,398 Corporate debt securities — 2,000 — 2,000 Total cash equivalents 4,398 2,000 — 6,398 Marketable Securities: — Corporate debt securities — 83,329 — 83,329 Government debt securities — 10,866 — 10,866 Total marketable securities — 94,195 — 94,195 Total cash equivalents and marketable securities $ 4,398 $ 96,195 $ — $ 100,593
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	Total notional and net fair values for foreign exchange derivative contracts designated as hedging instruments as of December 30, 2018 were as follows: Derivative Assets* Derivative Liabilities* Notional Amount Fair Value Notional Amount Fair Value (in thousands) Current assets $ 376 $ 3 Current liabilities $ 18,386 $ 908 Non-current assets** 2,630 28 Non-current liabilities** 3,050 82 Total foreign exchange contracts $ 3,006 $ 31 Total foreign exchange contracts $ 21,436 $ 990 * The Company recorded a net derivative liability of approximately $1.0 million as of December 30, 2018. There were no derivative assets or liabilities recorded in fiscal 2017. ** Non-current derivative assets and liabilities were discounted at the prevailing risk-free interest rate.
Schedule of Warrants	As of December 31, 2017 , warrants issued and outstanding were as follows: Date of Issuance Number of Warrants Exercise Price Expiration Date Common stock warrants September 2015 83,006 $ 2.50 February 2019

Derivative Instruments (Tables)

Derivative Instruments (Tables)	12 Months Ended
	Dec. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of derivative gain (loss)	The effects of derivative instruments and hedging activities on the consolidated statement of operations and its effect on the consolidated statement of comprehensive loss from changes in fair value for the year ended December 30, 2018 was as follows: Location and Amount of Loss Recognized for Hedging Activities: Consolidated Statement of Operations Consolidated Statement of Comprehensive Income (Loss)- (pre-tax) Research and Development Sales and Marketing General and Administrative Total (in thousands) Total expense from foreign currency hedging $ 414 $ 102 $ 27 $ 543 $ (959 ) Effects of foreign currency cashflow hedging: Loss reclassified from consolidated statement of comprehensive Income (loss) $ (414 ) $ (102 ) $ (27 ) $ (543 ) $ 543 Loss recognized in consolidated statement of comprehensive Income (loss) $ — $ — $ — $ — $ (1,502 )

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Rental Payments for Operating Leases	The Company conducts its operations using leased office facilities in various locations. The following is a schedule of future minimum lease payments under operating leases as of December 30, 2018 (in thousands): 2019 $ 2,862 2020 2,333 2021 1,899 2022 1,923 2023 1,809 2024 and beyond 318 Total minimum lease payments $ 11,144

Stockholders_ Equity (Tables)

Stockholders’ Equity (Tables)	12 Months Ended
	Dec. 30, 2018
Equity [Abstract]
Schedule of Stock by Class	The Company had reserved shares of common stock for issuance, on an as-converted basis, as follows: December 30, 2018 Options issued and outstanding 4,391,548 RSUs issued and outstanding 1,868,659 Shares available for ESPP 1,245,492 Shares available for future stock awards 2,563,564 10,069,263

Stock-based Compensation (Table

Stock-based Compensation (Tables)	12 Months Ended
	Dec. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs	Total stock-based compensation expense for employees and non-employees recognized in the consolidated statements of operations was as follows: Years Ended December 30, December 31, January 1, (in thousands) Cost of revenue $ 199 $ 165 $ 33 Research and development 9,676 5,616 911 Sales and marketing 2,696 1,763 248 General and administrative 4,718 3,139 1,898 Total stock-based compensation expense $ 17,289 $ 10,683 $ 3,090 The above stock-based compensation expense related to the following equity-based awards: Years Ended December 30, 2018 December 31, 2017 January 1, (in thousands) Stock options $ 4,171 $ 3,539 $ 3,090 RSU awards 11,187 5,368 — ESPP shares 1,931 1,776 — Total stock-based compensation expense $ 17,289 $ 10,683 $ 3,090
Schedule of Unrecognized Compensation Cost, Nonvested Awards	Unamortized compensation expense related to unvested stock awards was as follows (in thousands): December 30, 2018 December 31, 2017 Unamortized Expense Average Expected Recognition Period in Years Unamortized Expense Average Expected Recognition Period in Years Stock options $ 7,697 2.2 $ 9,275 2.8 RSU awards 23,206 2.3 16,272 2.7 ESPP shares 1,081 0.5 1,182 0.8 Total unamortized stock-based compensation expense $ 31,984 $ 26,729
Schedule of Share-based Compensation, Stock Options, Activity	The table below summarizes stock option activity under the 2016 Plan: Number of Number of Weighted– Weighted– Aggregate Balances at December 27, 2015 78,975 5,062,342 $ 1.77 7.4 $ 11,269 Authorized 6,113,092 — RSUs granted (6,950 ) — Granted (weighted–average fair value of $3.65 per share) (2,064,982 ) 2,064,982 8.99 Exercised — (403,769 ) 2.95 Expired, forfeited or canceled 249,931 (249,930 ) 3.14 Balances at January 1, 2017 4,370,066 6,473,625 3.95 7.4 91,840 Granted (weighted–average fair value of $7.91 per share) (703,283 ) 703,283 19.31 Exercised — (1,756,143 ) 1.86 Expired, forfeited or canceled 145,813 (145,813 ) 8.15 Balances at December 31, 2017 3,812,596 5,274,952 6.59 7.2 35,578 Granted (weighted–average fair value of $5.50 per share) (666,250 ) 666,250 13.06 Exercised — (1,293,541 ) 3.23 Expired, forfeited or canceled 256,113 (256,113 ) 12.55 Balances at December 30, 2018 3,402,459 4,391,548 8.21 6.6 30,148 Options vested and exercisable-December 30, 2018 2,626,213 5.57 5.8 24,411
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	The following assumptions were used to calculate the fair value of options granted to employees and non-employee directors during the years indicated: Years Ended December 30, December 31, January 1, Expected term (in years) 6.08 6.0 - 6.1 5.5 - 6.6 Volatility 40% 37% - 39% 39% - 40% Risk-free interest rate 2.4% 1.9% - 2.3% 1.1% - 2.1% Expected dividend — — — The following assumptions were used in estimating the fair value of employees' purchase rights under the ESPP: Years Ended December 30, December 31, Contractual term remaining (in years) 0.5 - 1.0 0.5 - 1.0 Volatility 31% - 57% 49% - 66% Risk-free interest rate 2.1% - 2.7% 1.4 % - 1.6% Expected dividend — —
Schedule of Share-based Compensation, Restricted Stock Units Award Activity	The table below summarizes RSU activity under the 2016 Plan: Number of Weighted– Aggregate Balances at January 1, 2017 6,950 3.9 $ 126 Granted (weighted–average fair value of $17.72 per share) 1,276,940 Vested (125,818 ) Forfeited or canceled (57,545 ) Balances at December 31, 2017 1,100,527 Granted (weighted–average fair value of $14.93 per share) 1,541,549 Vested (565,618 ) Forfeited or canceled (207,799 ) Balances at December 30, 2018 1,868,659 Outstanding and expected to vest at December 30, 2018 1,868,659 1.2 $ 26,423

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 30, 2018
Income Tax Disclosure [Abstract]
Schedule of Income before Income Tax, Domestic and Foreign	The components of loss before income taxes were as follows: Years Ended December 30, December 31, January 1, (in thousands) United States $ 3,001 $ 33,451 $ 16,535 Foreign 1,048 (33,981 ) (18,063 ) $ 4,049 $ (530 ) $ (1,528 )
Schedule of Components of Income Tax Expense (Benefit)	The components of the benefit (provision) for income taxes were as follows: Years Ended December 30, December 31, January 1, (in thousands) Federal $ — $ 290 $ (266 ) State (7 ) (16 ) (1 ) Foreign (960 ) (668 ) (132 ) Total current provision for income taxes (967 ) (394 ) (399 ) Federal (14 ) 35,303 — State (2 ) 65 — Foreign 17 (32 ) 32 Total deferred provision 1 35,336 32 $ (966 ) $ 34,942 $ (367 )
Schedule of Deferred Tax Assets and Liabilities	The material components of the deferred tax assets were as follows: December 30, December 31, (in thousands) Deferred tax assets: Accrual, reserve and other $ 1,578 $ 1,471 Depreciation and amortization (1,576 ) (1,625 ) Net operating loss and credits carry forwards 49,059 48,401 Stock based compensation 1,881 1,645 Other 252 64 Total gross deferred tax assets 51,194 49,956 Valuation allowance (15,643 ) (14,534 ) Total net deferred tax assets $ 35,551 $ 35,422
Schedule of Effective Income Tax Rate Reconciliation	A reconciliation of the Company’s effective tax rate to the statutory U.S. federal rate is as follows: Years Ended December 30, December 31, January 1, US Federal Rate 21.0 % 34.0 % 34.0 % State income taxes, net of federal benefit (26.2 ) 867.1 — Difference between statutory rate and foreign effective tax rate 18.5 (2,285.7 ) (437.8 ) Other permanent Items 5.5 (52.3 ) (125.2 ) Stock based compensation (36.5 ) 1,650.1 (29.2 ) Research and development credits (77.3 ) 610.3 102.2 Change in valuation allowance 27.4 8,988.6 477.6 Foreign Income 8.8 (96.1 ) (75.8 ) Foreign Tax Credit — — 30.7 True up 25.5 — — Uncertain tax position 57.2 — — Federal Rate Change — (3,128.1 ) — 23.9 % 6,587.9 % (23.5 )%
Unrecognized Tax Benefits	A reconciliation of the beginning and ending unrecognized tax benefit amount is as follows: December 30, December 31, January 1, (in thousands) Beginning balance $ 5,318 $ 5,221 $ 4,425 Increases related to current year’s unrecognized tax benefits 3,283 1,569 888 Increases related to prior year’s unrecognized tax benefits 107 68 — Decreases related to prior year’s unrecognized tax benefits (442 ) (1,540 ) (92 ) Ending balance $ 8,266 $ 5,318 $ 5,221
Summary of Valuation Allowance	The valuation allowance for deferred tax assets consisted of the following activity for the fiscal years 2018 , 2017 and 2016 : Balance at Beginning of Year Additions Reductions Balance at End of Year Allowance for deferred tax assets (in thousands) Year ended December 30, 2018 $ 14,534 $ 1,109 $ — $ 15,643 Year ended December 31, 2017 62,207 4,260 (51,933 ) 14,534 Year ended January 1, 2017 $ 67,194 $ 705 $ (5,692 ) $ 62,207

Segment Information and Opera_2

Segment Information and Operations by Geographic Area (Tables)	12 Months Ended
	Dec. 30, 2018
Segment Reporting [Abstract]
Schedule of Revenue from External Customers by Geographical Areas	The following table sets forth revenue by country, based on ship-to destinations, for countries with 10% or more of revenue during any of the periods presented: Years Ended December 30, December 31, January 1, Amount % of revenue Amount % of revenue Amount % of revenue (Dollars in thousands) China $ 123,383 56 % $ 119,821 68 % $ 86,107 66 % Vietnam 56,125 25 — — — — Taiwan 19,050 9 17,780 10 13,752 11 Tunisia 17,334 8 13,410 8 13,755 11 United States 111 — 283 — 291 — Other foreign countries 4,457 2 25,065 14 15,164 12 Total $ 220,460 100 % $ 176,359 100 % $ 129,069 100 % The following table sets forth the Company’s revenue by geographic region, based on ship-to destinations (in thousands): Years Ended December 30, 2018 December 31, 2017 January 1, 2017 Amount % of revenue Amount % of revenue Amount % of revenue Asia-Pacific $ 202,342 92 % $ 162,059 92 % $ 114,499 89 % Europe, Middle East and Africa 17,953 8 14,015 8 14,353 11 Americas 165 — 285 — 217 — Total $ 220,460 100 % $ 176,359 100 % $ 129,069 100 %

The Company and Summary of Si_4

The Company and Summary of Significant Accounting Policies (Concentration Risk) (Details) - Customer Concentration Risk	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
A | Sales Revenue, Services, Net
Concentration Risk [Line Items]
Concentration risk rate	29.00%	16.00%	11.00%
A | Accounts Receivable
Concentration Risk [Line Items]
Concentration risk rate	36.00%	31.00%
B | Sales Revenue, Services, Net
Concentration Risk [Line Items]
Concentration risk rate			19.00%
B | Accounts Receivable
Concentration Risk [Line Items]
Concentration risk rate	14.00%
C | Sales Revenue, Services, Net
Concentration Risk [Line Items]
Concentration risk rate			11.00%
C | Accounts Receivable
Concentration Risk [Line Items]
Concentration risk rate		12.00%
D | Accounts Receivable
Concentration Risk [Line Items]
Concentration risk rate	10.00%
E | Accounts Receivable
Concentration Risk [Line Items]
Concentration risk rate	10.00%	14.00%

The Company and Summary of Si_5

The Company and Summary of Significant Accounting Policies (Narrative) (Details) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017	Jan. 02, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Intangible asset		$ 5,100,000
Asset impairment charges		0	$ 0	$ 0
Amortization of intangible assets		$ 1,500,000
Warranty period		12 months
Estimate of breakage		$ 1,000,000
Customer discounts and rebates reversed	$ 2,000,000
Accumulated Deficit
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of new accounting principle in period of adoption				$ (54,000)
Adoption of ASU 2016-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred income tax liabilities, net					$ 54,000,000
Adoption of ASU 2016-09 | Accumulated Deficit
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of new accounting principle in period of adoption					$ 54,000

The Company and Summary of Si_6

The Company and Summary of Significant Accounting Policies (Property and Equipment Useful Lives) (Details)	12 Months Ended
	Dec. 30, 2018
Computer software
Property, Plant and Equipment [Line Items]
Useful life	3 years
Minimum | Computer and lab equipment
Property, Plant and Equipment [Line Items]
Useful life	3 years
Minimum | Furniture and fixtures
Property, Plant and Equipment [Line Items]
Useful life	3 years
Maximum | Computer and lab equipment
Property, Plant and Equipment [Line Items]
Useful life	5 years
Maximum | Furniture and fixtures
Property, Plant and Equipment [Line Items]
Useful life	7 years

Earnings Per Share (Schedule of

Earnings Per Share (Schedule of Eanings Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Earnings Per Share [Abstract]
Net income (loss)	$ 3,083	$ 34,412	$ (1,895)
Weighted-average shares outstanding - basic (in shares)	36,744	34,259	6,385
Dilutive effect of convertible preferred stock, warrants to purchase preferred stock, stock options, common stock warrants, ESPP and RSUs (in shares)	2,919	4,225	0
Weighted average shares used to compute diluted net (income) loss per share (in shares)	39,663	38,484	6,385
Net income (loss) per share:
Basic (dollars per share)	$ 0.08	$ 1	$ (0.30)
Diluted (dollars per share)	$ 0.08	$ 0.89	$ (0.30)

Earnings Per Share (Schedule _2

Earnings Per Share (Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share) (Details) - shares shares in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation (in shares)	1,375	1,952	7,182
Warrants to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation (in shares)	0	0	477
Shares available for ESPP
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation (in shares)	24	0	224
Restricted Stock Units (RSUs)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation (in shares)	40	1,095	7
Options to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation (in shares)	1,311	857	6,474

Balance Sheets Components (Mark

Balance Sheets Components (Marketable Securities) (Details) - USD ($) $ in Thousands	Dec. 30, 2018	Dec. 31, 2017
Schedule of Investments [Line Items]
Amortized Cost	$ 97,494	$ 94,459
Gross Unrealized Gains	26	7
Gross Unrealized Losses	(252)	(271)
Fair Value	97,268	94,195
Corporate debt securities
Schedule of Investments [Line Items]
Amortized Cost	85,353	83,570
Gross Unrealized Gains	24	7
Gross Unrealized Losses	(242)	(250)
Fair Value	85,135	83,327
Government debt securities
Schedule of Investments [Line Items]
Amortized Cost	12,141	10,889
Gross Unrealized Gains	2	0
Gross Unrealized Losses	(10)	(21)
Fair Value	$ 12,133	$ 10,868

Balance Sheets Components (Amor

Balance Sheets Components (Amortized Cost and Fair Value) (Details) - USD ($) $ in Thousands	Dec. 30, 2018	Dec. 31, 2017
Amortized Cost
Due in one year or less	$ 80,041	$ 49,201
Due after one year to five years	17,453	45,258
Amortized Cost	97,494	94,459
Fair Value
Due in one year or less	79,840	49,144
Due after one year to five years	17,428	45,051
Total, fair value	$ 97,268	$ 94,195

Balance Sheets Components (Sche

Balance Sheets Components (Schedule of Property and Equipment) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 25,223	$ 20,656
Accumulated depreciation and amortization	(11,532)	(8,145)
Property and equipment, net	13,691	12,511
Depreciation and amortization	4,861	2,669	$ 1,278
Computer and lab equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	17,858	14,295
Computer software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,047	795
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,739	1,589
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	4,579	3,977
Tangible Assets
Property, Plant and Equipment [Line Items]
Depreciation and amortization	$ 3,600	$ 2,400	$ 1,300

Balance Sheets Components (Sc_2

Balance Sheets Components (Schedule of Inventory) (Details) - USD ($) $ in Thousands	Dec. 30, 2018	Dec. 31, 2017
Balance Sheets Components [Abstract]
Raw materials	$ 9,069	$ 5,812
Work in progress	1,093	1,069
Finished goods	10,056	5,781
Inventory, gross	$ 20,218	$ 12,662

Balance Sheets Components (Accr

Balance Sheets Components (Accrued Liabilities and Other Current Liabilities) (Details) - USD ($) $ in Thousands	Dec. 30, 2018	Dec. 31, 2017
Balance Sheets Components [Abstract]
Accrued customer rebates	$ 10,705	$ 8,710
Accrued payroll and related benefits	6,424	3,411
Accrued expenses	3,004	4,507
Accrual for inventory purchases	1,214	2,124
ESPP employee contributions	1,043	706
Other	3,556	1,607
Accrued liabilities and other current liabilities	$ 25,946	$ 21,065

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details)	Dec. 30, 2018$ / shares
Measurement Input, Exercise Price | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value assumption (usd per share)	1

Fair Value Measurements (Assets

Fair Value Measurements (Assets, Recurring Basis) (Details) - USD ($) $ in Thousands	Dec. 30, 2018	Dec. 31, 2017
Assets:
Cash equivalents	$ 0	$ 0
Marketable securities	97,268	94,195
Fair Value, Measurements, Recurring
Assets:
Cash equivalents	5,214	6,398
Marketable securities	97,268	94,195
Total cash equivalents and marketable securities	102,482	100,593
Fair Value, Measurements, Recurring | Level 1
Assets:
Cash equivalents	3,170	4,398
Marketable securities	0	0
Total cash equivalents and marketable securities	3,170	4,398
Fair Value, Measurements, Recurring | Level 2
Assets:
Cash equivalents	2,044	2,000
Marketable securities	97,268	94,195
Total cash equivalents and marketable securities	99,312	96,195
Fair Value, Measurements, Recurring | Level 3
Assets:
Marketable securities	0	0
Total cash equivalents and marketable securities	0	0
Money market funds | Fair Value, Measurements, Recurring
Assets:
Cash equivalents	3,170	4,398
Money market funds | Fair Value, Measurements, Recurring | Level 1
Assets:
Cash equivalents	3,170	4,398
Money market funds | Fair Value, Measurements, Recurring | Level 2
Assets:
Cash equivalents	0	0
Money market funds | Fair Value, Measurements, Recurring | Level 3
Assets:
Cash equivalents	0	0
Corporate debt securities | Fair Value, Measurements, Recurring
Assets:
Cash equivalents	2,044	2,000
Marketable securities	85,136	83,329
Corporate debt securities | Fair Value, Measurements, Recurring | Level 1
Assets:
Cash equivalents	0	0
Marketable securities	0	0
Corporate debt securities | Fair Value, Measurements, Recurring | Level 2
Assets:
Cash equivalents	2,044	2,000
Marketable securities	85,136	83,329
Corporate debt securities | Fair Value, Measurements, Recurring | Level 3
Assets:
Cash equivalents	0	0
Marketable securities	0	0
Government debt securities | Fair Value, Measurements, Recurring
Assets:
Marketable securities	12,132	10,866
Government debt securities | Fair Value, Measurements, Recurring | Level 1
Assets:
Marketable securities	0	0
Government debt securities | Fair Value, Measurements, Recurring | Level 2
Assets:
Marketable securities	12,132	10,866
Government debt securities | Fair Value, Measurements, Recurring | Level 3
Assets:
Marketable securities	$ 0	$ 0

Fair Value Measurements (Common

Fair Value Measurements (Common Stock Warrants) (Details) - USD ($)	Dec. 30, 2018	Dec. 31, 2017
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)	$ 0
September 2,015
Class of Warrant or Right [Line Items]
Warrants exercised (in shares)	83,006
Exercise Price (usd per share)	$ 2.50	$ 2.50
Number of Warrants (in shares)		83,006
Number of Warrants Issued (in shares)		83,006

Fair Value Measurements (Fair V

Fair Value Measurements (Fair Value of Derivatives) (Details) - USD ($)	Dec. 30, 2018	Dec. 31, 2017
Assets:
Derivative liability	$ 1,000,000	$ 0
Foreign Exchange Forward | Designated as Hedging Instrument
Assets:
Derivative Asset, Notional Amount	3,006,000
Derivative Asset, Fair Value	31,000
Derivative Liability, Notional Amount	21,436,000
Derivative Liability, Fair Value	990,000
Foreign Exchange Forward | Designated as Hedging Instrument | Current Assets
Assets:
Derivative Asset, Notional Amount	376,000
Derivative Asset, Fair Value	3,000
Foreign Exchange Forward | Designated as Hedging Instrument | Noncurrent Assets
Assets:
Derivative Asset, Notional Amount	2,630,000
Derivative Asset, Fair Value	28,000
Foreign Exchange Forward | Designated as Hedging Instrument | Current Liabilities
Assets:
Derivative Liability, Notional Amount	18,386,000
Derivative Liability, Fair Value	908,000
Foreign Exchange Forward | Designated as Hedging Instrument | Noncurrent Liabilities
Assets:
Derivative Liability, Notional Amount	3,050,000
Derivative Liability, Fair Value	$ 82,000

Derivative Instruments (Locatio

Derivative Instruments (Location and Amount of Gain or (Loss) Recognized in Income on Fair Value and Cash Flow Hedging Relationships) (Details) $ in Thousands	12 Months Ended
	Dec. 30, 2018USD ($)
Derivative Instruments, Gain (Loss) [Line Items]
Loss reclassified from consolidated statement of comprehensive Income (loss)	$ (785)
Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Loss recognized in consolidated statement of comprehensive Income (loss)	0
Designated as Hedging Instrument | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Loss reclassified from consolidated statement of comprehensive Income (loss)	(543)
Condensed Consolidated Statement of Comprehensive Loss (pre-tax) | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Loss recognized in consolidated statement of comprehensive Income (loss)	(1,502)
Condensed Consolidated Statement of Comprehensive Loss (pre-tax) | Designated as Hedging Instrument | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Loss reclassified from consolidated statement of comprehensive Income (loss)	543
Research and development | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Loss recognized in consolidated statement of comprehensive Income (loss)	0
Research and development | Designated as Hedging Instrument | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Loss reclassified from consolidated statement of comprehensive Income (loss)	(414)
Sales and marketing | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Loss recognized in consolidated statement of comprehensive Income (loss)	0
Sales and marketing | Designated as Hedging Instrument | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Loss reclassified from consolidated statement of comprehensive Income (loss)	(102)
General and administrative | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Loss recognized in consolidated statement of comprehensive Income (loss)	0
General and administrative | Designated as Hedging Instrument | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Loss reclassified from consolidated statement of comprehensive Income (loss)	(27)
Foreign Exchange Forward | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Total expense from foreign currency hedging	543
Foreign Exchange Forward | Condensed Consolidated Statement of Comprehensive Loss (pre-tax) | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Total expense from foreign currency hedging	(959)
Foreign Exchange Forward | Research and development | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Total expense from foreign currency hedging	414
Foreign Exchange Forward | Sales and marketing | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Total expense from foreign currency hedging	102
Foreign Exchange Forward | General and administrative | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Total expense from foreign currency hedging	$ 27

Commitments and Contingencies_2

Commitments and Contingencies (Details) $ in Thousands	Dec. 30, 2018USD ($)
Commitments and Contingencies Disclosure [Abstract]
2,019	$ 2,862
2,020	2,333
2,021	1,899
2,022	1,923
2,023	1,809
2024 and beyond	318
Total minimum lease payments	$ 11,144

Commitments and Contingencies_3

Commitments and Contingencies (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Other Commitments [Line Items]
Rent expense	$ 2,900,000	$ 1,900,000	$ 1,200,000
Purchase obligation	11,400,000
Indemnification Agreement
Other Commitments [Line Items]
Obligations	$ 0

Commitments and Contingencies_4

Commitments and Contingencies (RUSNANO) (Details) - Investor - Agreement with RUSNANO $ in Millions	Dec. 31, 2014period	Jul. 31, 2014USD ($)period
Related Party Transaction [Line Items]
Contractual obligation		$ 13
Annual periods | period	6	6
Contractual obligation, year 1		$ 2.2
Contractual obligation, year 2		1.7
Contractual obligation, year 3		2
Contractual obligation, year 4		2.2
Contractual obligation, year 5		2.4
Contractual obligation, year 6		$ 2.5
Funding obligation penalty		10.00%
Difference between the funding obligation and the actual funding		80.00%

Commitments and Contingencies_5

Commitments and Contingencies (Narrative 2) (Details) $ in Millions	Dec. 30, 2018USD ($)
Software License Arrangement
Other Commitments [Line Items]
Contractual obligation	$ 2.6
Contractual obligation, year 1	1.5
Contractual obligation, year 2	1.1
Intellectual Property Licenses
Other Commitments [Line Items]
Contractual obligation	2.5
Design Win Solutions
Other Commitments [Line Items]
Contractual obligation	$ 4.3

Long-term Debt (Narrative) (Det

Long-term Debt (Narrative) (Details) - USD ($) $ in Thousands	Dec. 30, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
Long-term debt, current portion	$ 0	$ 3,943

Stockholders_ Equity (Details)

Stockholders’ Equity (Details)	Dec. 30, 2018vote$ / sharesshares	Dec. 31, 2017$ / sharesshares
Equity [Abstract]
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock, par value (in usd per share) | $ / shares	$ 0.0001	$ 0.0001
Votes per share | vote	1
Options issued and outstanding (in shares)	4,391,548
RSUs issued and outstanding (in shares)	1,868,659
Shares available for ESPP (in shares)	1,245,492
Shares available for future stock awards (in shares)	2,563,564
Shares reserved for future issuance (in shares)	10,069,263

Stock-based Compensation (Narra

Stock-based Compensation (Narrative) (Details) $ in Millions	1 Months Ended	12 Months Ended
	Nov. 30, 2016shares	Dec. 30, 2018USD ($)shares	Dec. 31, 2017USD ($)shares	Jan. 01, 2017USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grants (in shares)		2,563,564
Vesting period		4 years
Aggregate intrinsic value of options exercised | $		$ 16.5	$ 29	$ 2.6
Repurchase rights expiration per month of shares		0.0278
2016 Employee Stock Purchase Plan | ESPP shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grants (in shares)	4,100,000
Conditional increase of shares (in shares)	3,400,000
Conditional increase of shares rate	5.00%
Exercisable term		10 years
Vesting period		4 years
Maximum subscription rate		20.00%
Stock issued (in shares)		400,696	353,812
Stock authorized for repurchase (in shares)		1,245,492
Minimum | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Maximum | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years

Stock-based Compensation (Compe

Stock-based Compensation (Compensation Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 17,289	$ 10,683	$ 3,090
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	199	165	33
Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	9,676	5,616	911
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	2,696	1,763	248
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 4,718	$ 3,139	$ 1,898

Stock-based Compensation (Equit

Stock-based Compensation (Equity Based Awards Compensation Costs) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 17,289	$ 10,683	$ 3,090
Stock options
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	4,171	3,539	3,090
RSU awards
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	11,187	5,368	0
ESPP shares
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 1,931	$ 1,776	$ 0

Stock-based Compensation (Sched

Stock-based Compensation (Schedule of Unrecognized Compensation Cost, Nonvested Awards) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized Expense, Stock options	$ 7,697	$ 9,275
Total unamortized stock-based compensation expense	$ 31,984	$ 26,729
Average Expected Recognition Period in Years	2 years 2 months 6 days	2 years 9 months 6 days
RSU awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized Expense	$ 23,206	$ 16,272
Average Expected Recognition Period in Years	2 years 4 months 6 days	2 years 8 months 6 days
ESPP shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized Expense	$ 1,081	$ 1,182
Average Expected Recognition Period in Years	6 months 6 days	9 months 6 days

Stock-based Compensation (Sch_2

Stock-based Compensation (Schedule of Share-based Compensation, Stock Options, Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017	Dec. 27, 2015
Number of Shares Available for Issuance
Ending balance (in shares)	2,563,564
Number of Shares Outstanding
Ending balance (in shares)	4,391,548
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted average fair value (usd per share)	$ 5.50	$ 7.91	$ 3.65
Stock options
Number of Shares Available for Issuance
Beginning balance (in shares)	3,812,596	4,370,066	78,975
Authorized (in shares)				6,113,092
Granted (in shares)	(666,250)	(703,283)	(2,064,982)
Expired, forfeited or canceled (in shares)	256,113	145,813	249,931
Ending balance (in shares)	3,402,459	3,812,596	4,370,066
Number of Shares Outstanding
Beginning balance (in shares)	5,274,952	6,473,625	5,062,342
Granted (in shares)	666,250	703,283	2,064,982
Exercised (in shares)	(1,293,541)	(1,756,143)	(403,769)
Expired, forfeited or canceled (in shares)	(256,113)	(145,813)	(249,930)
Ending balance (in shares)	4,391,548	5,274,952	6,473,625
Options vested and exercisable-December 30, 2018 (in shares)	2,626,213
Weighted– Average Exercise Price
Beginning balance (usd per share)	$ 6.59	$ 3.95	$ 1.77
Granted (usd per share)	13.06	19.31	8.99
Exercised (usd per share)	3.23	1.86	2.95
Expired, forfeited or canceled (usd per share)	12.55	8.15	3.14
Ending balance (usd per share)	8.21	$ 6.59	$ 3.95
Options Exercisable-December 31, 2018 (usd per share)	$ 5.57
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted-average remaining contractual term	6 years 7 months 6 days	7 years 2 months 6 days	7 years 4 months 8 days
Weighted-average remaining contractual term, Options Exercisable	5 years 10 months 6 days
Aggregate intrinsic value	$ 30,148	$ 35,578	$ 91,840	$ 11,269
Aggregate intrinsic value, options exercisable	$ 24,411
Restricted Stock Units (RSUs)
Number of Shares Available for Issuance
Granted (in shares)	(1,541,549)	(1,276,940)	(6,950)

Stock-based Compensation (Fair

Stock-based Compensation (Fair Value Assumptions) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	6 years 29 days
Volatility	40.00%
Volatility, minimum		37.00%	39.00%
Volatility, maximum		39.00%	40.00%
Risk-free interest rate	2.40%
Risk-free interest rate, minimum		1.90%	1.10%
Risk-free interest rate, maximum		2.30%	2.10%
Expected dividend	$ 0	$ 0	$ 0
ESPP shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility, minimum	31.00%	49.00%
Volatility, maximum	57.00%	66.00%
Risk-free interest rate, minimum	2.10%	1.40%
Risk-free interest rate, maximum	2.70%	1.60%
Expected dividend	$ 0	$ 0
Minimum | Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)		6 years	5 years 6 months
Minimum | ESPP shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	6 months	6 months
Maximum | Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)		6 years 1 month 6 days	6 years 7 months 6 days
Maximum | ESPP shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	1 year	1 year

Stock-based Compensation (Restr

Stock-based Compensation (Restricted Stock Units) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Weighted average fair value (usd per share)	$ 14.93	$ 17.72
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Beginning balance (in shares)	1,100,527	6,950
Granted (in shares)	1,541,549	1,276,940	6,950
Vested (in shares)	(565,618)	(125,818)
Forfeited or canceled (in shares)	(207,799)	(57,545)
Ending balance (in shares)	1,868,659	1,100,527	6,950
Outstanding and expected to vest (in shares)	1,868,659
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Weighted average remaining contractual term	1 year 2 months 6 days	3 years 11 months 6 days
Aggregate intrinsic value, outstanding and expected to vest	$ 26,423		$ 126

Income Taxes (Schedule of Incom

Income Taxes (Schedule of Income before Income Tax, Domestic and Foreign) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Income Tax Disclosure [Abstract]
United States	$ 3,001	$ 33,451	$ 16,535
Foreign	1,048	(33,981)	(18,063)
Income (loss) before income taxes	$ 4,049	$ (530)	$ (1,528)

Income Taxes (Schedule of Compo

Income Taxes (Schedule of Components of Income Tax Expense (Benefit)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Income Tax Disclosure [Abstract]
Federal	$ 0	$ 290	$ (266)
State	(7)	(16)	(1)
Foreign	(960)	(668)	(132)
Total current provision for income taxes	(967)	(394)	(399)
Federal	(14)	35,303	0
State	(2)	65	0
Foreign	17	(32)	32
Total deferred provision	1	35,336	32
Income tax expense (benefit)	$ (966)	$ 34,942	$ (367)

Income Taxes (Schedule of Defer

Income Taxes (Schedule of Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017	Dec. 27, 2015
Deferred tax assets:
Accrual, reserve and other	$ 1,578	$ 1,471
Depreciation and amortization	(1,576)	(1,625)
Net operating loss and credits carry forwards	49,059	48,401
Stock based compensation	1,881	1,645
Other	252	64
Total gross deferred tax assets	51,194	49,956
Valuation allowance	(15,643)	(14,534)	$ (62,207)	$ (67,194)
Total net deferred tax assets	$ 35,551	$ 35,422

Income Taxes (Schedule of Effec

Income Taxes (Schedule of Effective Income Tax Rate Reconciliation) (Details)	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Income Tax Disclosure [Abstract]
US Federal Rate	21.00%	34.00%	34.00%
State income taxes, net of federal benefit	(26.20%)	867.10%	0.00%
Difference between statutory rate and foreign effective tax rate	18.50%	(2285.70%)	(437.80%)
Other permanent Items	5.50%	(52.30%)	(125.20%)
Stock based compensation	(36.50%)	1650.10%	(29.20%)
Research and development credits	(77.30%)	610.30%	102.20%
Change in valuation allowance	27.40%	8988.60%	477.60%
Foreign Income	8.80%	(96.10%)	(75.80%)
Foreign Tax Credit	0.00%	0.00%	30.70%
True up	25.50%	0.00%	0.00%
Uncertain tax position	57.20%	0.00%	0.00%
Federal Rate Change	0.00%	(3128.10%)	0.00%
Effective Income Tax Rate Reconciliation, Percent	23.90%	6587.90%	(23.50%)

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017	Dec. 27, 2015
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 117,000	$ 120,200
Unrecognized tax benefits	8,266	5,318	$ 5,221	$ 4,425
Unrecognized tax benefits that would impact effective tax rate	5,600
Undistributed earnings of foreign subsidiaries	9,700
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	92,400	104,600
Research Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Tax credit carryforward	14,900	10,600
Research Tax Credit Carryforward | State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Tax credit carryforward	$ 13,500	$ 11,000

Income Taxes (Unrecognized Tax

Income Taxes (Unrecognized Tax Benefits) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	$ 5,318	$ 5,221	$ 4,425
Increases related to current year’s unrecognized tax benefits	3,283	1,569	888
Increases related to prior year’s unrecognized tax benefits	107	68	0
Decreases related to prior year’s unrecognized tax benefits	(442)	(1,540)	(92)
Ending balance	$ 8,266	$ 5,318	$ 5,221

Income Taxes (Valuation Allowan

Income Taxes (Valuation Allowance) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Valuation Allowance [Roll Forward]
Balance at Beginning of Year	$ 14,534	$ 62,207	$ 67,194
Additions	1,109	4,260	705
Reductions	0	(51,933)	(5,692)
Balance at End of Year	$ 15,643	$ 14,534	$ 62,207

Employee Benefit Plans (Details

Employee Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017
Retirement Benefits [Abstract]
Contribution amount by Company	$ 0.5	$ 0.5

Segment Information and Opera_3

Segment Information and Operations by Geographic Area (Narrative) (Details)	12 Months Ended
	Dec. 30, 2018segment
Segment Reporting [Abstract]
Number of operating segments	1

Segment Information and Opera_4

Segment Information and Operations by Geographic Area (Schedule of Revenue by Geographical Area) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 220,460	$ 176,359	$ 129,069
Geographic Concentration Risk | Sales Revenue, Services, Net
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 220,460	$ 176,359	$ 129,069
Percentage of revenue	100.00%	100.00%	100.00%
Geographic Concentration Risk | Sales Revenue, Services, Net | Asia-Pacific
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 202,342	$ 162,059	$ 114,499
Percentage of revenue	92.00%	92.00%	89.00%
Geographic Concentration Risk | Sales Revenue, Services, Net | Europe, Middle East and Africa
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 17,953	$ 14,015	$ 14,353
Percentage of revenue	8.00%	8.00%	11.00%
Geographic Concentration Risk | Sales Revenue, Services, Net | Americas
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 165	$ 285	$ 217
Percentage of revenue	0.00%	0.00%	0.00%
Geographic Concentration Risk | Sales Revenue, Services, Net | China
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 123,383	$ 119,821	$ 86,107
Percentage of revenue	56.00%	68.00%	66.00%
Geographic Concentration Risk | Sales Revenue, Services, Net | Vietnam
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 56,125	$ 0	$ 0
Percentage of revenue	25.00%	0.00%	0.00%
Geographic Concentration Risk | Sales Revenue, Services, Net | Taiwan
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 19,050	$ 17,780	$ 13,752
Percentage of revenue	9.00%	10.00%	11.00%
Geographic Concentration Risk | Sales Revenue, Services, Net | Tunisia
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 17,334	$ 13,410	$ 13,755
Percentage of revenue	8.00%	8.00%	11.00%
Geographic Concentration Risk | Sales Revenue, Services, Net | United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 111	$ 283	$ 291
Percentage of revenue	0.00%	0.00%	0.00%
Geographic Concentration Risk | Sales Revenue, Services, Net | Other foreign countries
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 4,457	$ 25,065	$ 15,164
Percentage of revenue	2.00%	14.00%	12.00%

Related Party transactions (Pur

Related Party transactions (Purchases from Cadence Design Systems, Inc.) (Details) - USD ($) $ in Millions	Jul. 01, 2018	Jul. 01, 2018	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Related Party Transaction [Line Items]
Intangible asset			$ 5.1
Amortization of intangible assets			$ 1.5
Software License Arrangement | Lip-Bu Tan
Related Party Transaction [Line Items]
Intangible asset	$ 2.4	$ 2.4
Amortization of intangible assets	$ 0.8	$ 0.5		$ 3
Purchases from related party					$ 1.7

Related Party transactions (Agr

Related Party transactions (Agreement with RUSNANO) (Details) - Investor - Agreement with RUSNANO $ in Millions	Dec. 31, 2014period	Jul. 31, 2014USD ($)period
Related Party Transaction [Line Items]
Contractual obligation		$ 13
Annual periods | period	6	6
Contractual obligation, year 1		$ 2.2
Contractual obligation, year 2		1.7
Contractual obligation, year 3		2
Contractual obligation, year 4		2.2
Contractual obligation, year 5		2.4
Contractual obligation, year 6		$ 2.5
Funding obligation penalty		10.00%
Difference between the funding obligation and the actual funding		80.00%