Everspin (MRAM) 10-Q 7 Aug 19 2019 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2019	Jul. 31, 2019
Document And Entity Information
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Entity Registrant Name	EVERSPIN TECHNOLOGIES INC
Entity Central Index Key	0001438423
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		17,151,478
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Shell Company	false

Condensed Balance Sheets

Condensed Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 15,273	$ 23,379
Accounts receivable, net	5,864	7,522
Inventory	8,964	9,097
Prepaid expenses and other current assets	488	688
Total current assets	30,589	40,686
Property and equipment, net	3,867	4,286
Right-of-use assets	2,947
Other assets	73	73
Total assets	37,476	45,045
Current liabilities:
Accounts payable	2,197	2,637
Accrued liabilities	3,704	5,001
Current portion of long-term debt	5,977	5,977
Lease liabilities	1,583
Total current liabilities	13,461	13,615
Long-term debt, net of current portion	3,642	6,509
Lease liabilities, net of current portion	1,726
Total liabilities	18,829	20,124
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.0001 par value per share; 5,000,000 shares authorized; no shares issued and outstanding as of June 30, 2019 and December 31, 2018
Common stock, $0.0001 par value per share; 100,000,000 shares authorized; 17,151,290 and 17,095,456 shares issued and outstanding as of June 30, 2019 and December 31, 2018	2	2
Additional paid-in capital	160,564	158,912
Accumulated deficit	(141,919)	(133,993)
Total stockholders’ equity	18,647	24,921
Total liabilities and stockholders’ equity	$ 37,476	$ 45,045

Condensed Balance Sheets (Paren

Condensed Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2019	Dec. 31, 2018
Condensed Balance Sheets
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares Issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	17,151,290	17,095,456
Common stock, shares outstanding	17,151,290	17,095,456

Condensed Statements of Operati

Condensed Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Total revenue	$ 8,646	$ 10,765	$ 18,672	$ 25,618
Cost of sales	4,627	6,229	9,868	11,127
Gross profit	4,019	4,536	8,804	14,491
Operating expenses:
Research and development	3,519	6,773	7,517	13,253
General and administrative	2,856	3,329	6,451	6,548
Sales and marketing	1,239	1,713	2,603	3,079
Total operating expenses	7,614	11,815	16,571	22,880
Loss from operations	(3,595)	(7,279)	(7,767)	(8,389)
Interest expense	(186)	(222)	(397)	(433)
Other income, net	111	132	238	176
Net loss and comprehensive loss	$ (3,670)	$ (7,369)	$ (7,926)	$ (8,646)
Net loss per common share, basic and diluted	$ (0.21)	$ (0.44)	$ (0.46)	$ (0.55)
Weighted-average shares used to compute net loss per common share, basic and diluted	17,137,338	16,635,261	17,117,777	15,717,248
Product sales
Total revenue	$ 8,003	$ 9,449	$ 17,026	$ 18,814
Product sales
Total revenue	8,003	9,449	17,026	18,814
Licensing, royalty and other revenue
Total revenue	$ 643	$ 1,316	$ 1,646	$ 6,804

Condensed Statements of Stockho

Condensed Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Total
Balance at Dec. 31, 2017	$ 1	$ 128,422	$ (117,539)	$ 10,884
Balance (in shares) at Dec. 31, 2017	12,817,201
Increase (Decrease) in Stockholders' Equity
Adjustment to opening balance for adoption of new accounting standard			1,300	1,300
Issuance of common stock in secondary offering, net of issuance costs	$ 1	24,608		24,609
Issuance of common stock in secondary offering, net of issuance costs (in shares)	3,772,447
Issuance of common stock under stock incentive plans		309		309
Issuance of common stock under stock incentive plans (in shares)	58,229
Compensation expense related to vesting of common stock issued to GLOBALFOUNDRIES		237		237
Stock-based compensation expense		625		625
Net loss			(1,277)	(1,277)
Balance at Mar. 31, 2018	$ 2	154,201	(117,516)	36,687
Balance (in shares) at Mar. 31, 2018	16,647,877
Balance at Dec. 31, 2017	$ 1	128,422	(117,539)	10,884
Balance (in shares) at Dec. 31, 2017	12,817,201
Increase (Decrease) in Stockholders' Equity
Net loss				(8,646)
Balance at Jun. 30, 2018	$ 2	155,866	(124,885)	30,983
Balance (in shares) at Jun. 30, 2018	16,800,505
Balance at Mar. 31, 2018	$ 2	154,201	(117,516)	36,687
Balance (in shares) at Mar. 31, 2018	16,647,877
Increase (Decrease) in Stockholders' Equity
Issuance of common stock under stock incentive plans		723		723
Issuance of common stock under stock incentive plans (in shares)	152,628
Compensation expense related to vesting of common stock issued to GLOBALFOUNDRIES		225		225
Stock-based compensation expense		717		717
Net loss			(7,369)	(7,369)
Balance at Jun. 30, 2018	$ 2	155,866	(124,885)	30,983
Balance (in shares) at Jun. 30, 2018	16,800,505
Balance at Dec. 31, 2018	$ 2	158,912	(133,993)	24,921
Balance (in shares) at Dec. 31, 2018	17,095,456
Increase (Decrease) in Stockholders' Equity
Issuance of common stock under stock incentive plans		13		13
Issuance of common stock under stock incentive plans (in shares)	12,607
Stock-based compensation expense		704		704
Net loss			(4,256)	(4,256)
Balance at Mar. 31, 2019	$ 2	159,629	(138,249)	21,382
Balance (in shares) at Mar. 31, 2019	17,108,063
Balance at Dec. 31, 2018	$ 2	158,912	(133,993)	24,921
Balance (in shares) at Dec. 31, 2018	17,095,456
Increase (Decrease) in Stockholders' Equity
Net loss				(7,926)
Balance at Jun. 30, 2019	$ 2	160,564	(141,919)	18,647
Balance (in shares) at Jun. 30, 2019	17,151,290
Balance at Mar. 31, 2019	$ 2	159,629	(138,249)	21,382
Balance (in shares) at Mar. 31, 2019	17,108,063
Increase (Decrease) in Stockholders' Equity
Issuance of common stock under stock incentive plans		137		137
Issuance of common stock under stock incentive plans (in shares)	43,227
Stock-based compensation expense		798		798
Net loss			(3,670)	(3,670)
Balance at Jun. 30, 2019	$ 2	$ 160,564	$ (141,919)	$ 18,647
Balance (in shares) at Jun. 30, 2019	17,151,290

Condensed Statement of Cash Flo

Condensed Statement of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash flows from operating activities
Net loss	$ (7,926)	$ (8,646)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	876	729
Loss on disposal of property and equipment	20	19
Stock-based compensation	1,502	1,342
Non-cash interest expense	153	200
Compensation expense related to vesting of common stock to GLOBALFOUNDRIES		462
Changes in operating assets and liabilities:
Accounts receivable	1,658	(1,391)
Inventory	133	940
Prepaid expenses and other current assets	200	(635)
Right-of-use assets	23
Other assets		(136)
Accounts payable	(456)	51
Accrued liabilities	(907)	2,591
Lease liabilities	(43)
Shipping term reversal		(39)
Net cash used in operating activities	(4,790)	(4,513)
Cash flows from investing activities
Purchases of property and equipment	(461)	(347)
Net cash used in investing activities	(461)	(347)
Cash flows from financing activities
Proceeds from the issuance of common stock, net of offering costs		24,609
Payments on debt	(3,000)	(1,000)
Payments on finance lease obligation	(5)	(6)
Proceeds from exercise of stock options and purchase of shares in employee stock purchase plan	150	1,032
Net cash (used in) provided by financing activities	(2,855)	24,635
Net (decrease) increase in cash and cash equivalents	(8,106)	19,775
Cash and cash equivalents at beginning of period	23,379	12,950
Cash and cash equivalents at end of period	15,273	32,725
Supplementary cash flow information:
Interest paid	257	233
Operating cash flows paid for operating leases	837
Financing cash flows paid for finance leases	5
Right-of-use assets obtained in exchange for new operating leases	23
Non-cash investing and financing activities:
Purchases of property and equipment in accounts payable	$ 27	$ 27

Organization and Nature of Busi

Organization and Nature of Business	6 Months Ended
	Jun. 30, 2019
Organization and Nature of Business
Organization and Nature of Business	1. Organization and Nature of Business Everspin Technologies, Inc. (the Company) was incorporated in Delaware on May 16, 2008. The Company’s magnetoresistive random-access memory (MRAM) solutions offer the persistence of non-volatile memory with the speed and endurance of random-access memory (RAM) and enable the protection of mission critical data particularly in the event of power interruption or failure. The Company’s MRAM solutions allow its customers in the industrial, automotive, transportation, and enterprise storage markets to design high performance, power efficient and reliable systems without the need for bulky batteries or capacitors. Ability to continue as a going concern The Company believes that its existing cash and cash equivalents as of June 30, 2019, coupled with its anticipated growth and sales levels will be sufficient to meet its anticipated cash requirements for at least the next twelve months from the financial statement issuance date. The Company’s future capital requirements will depend on many factors, including its growth rate, the timing and extent of its spending to support research and development activities, the timing and cost of establishing additional sales and marketing capabilities, and the introduction of new products. The Company may be required at some point in the future to seek additional equity or debt financing, to sustain operations beyond that point, and such additional financing may not be available on acceptable terms or at all. If the Company is unable to raise additional capital or generate sufficient cash from operations to adequately fund its operations, it will need to curtail planned activities to reduce costs. Doing so will likely harm its ability to execute on its business plan.

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2019
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation The accompanying unaudited condensed financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (GAAP) and applicable rules and regulations of the Securities and Exchange Commission (SEC) regarding interim financial reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by GAAP have been condensed or omitted, and accordingly the balance sheet as of December 31, 2018 has been derived from the audited financial statements at that date but does not include all of the information required by GAAP for complete financial statements. These unaudited interim condensed financial statements have been prepared on the same basis as the Company’s annual financial statements and, in the opinion of management, reflect all adjustments (consisting only of normal recurring adjustments) that are necessary for a fair statement of the Company’s financial information. The results of operations for the three and six months ended June 30, 2019 are not necessarily indicative of the results to be expected for the year ending December 31, 2019 or for any other interim period or for any other future year. The accompanying condensed financial statements and related financial information should be read in conjunction with the audited financial statements and the related notes thereto for the year ended December 31, 2018, included in the Company’s Annual Report on Form 10-K filed with the SEC. Use of Estimates The preparation of the condensed financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the condensed financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, management evaluates its estimates, including those related to revenue recognition, fair value of assets and liabilities, inventory, product warranty reserves, income taxes, and stock-based compensation. The Company believes its estimates and assumptions are reasonable; however, actual results may differ from the Company’s estimates. Accounts receivable, net The Company estimates credits to distributors based on the historical rate of credits provided to distributors relative to sales. At June 30, 2019, the allowance for product returns and the allowance for price concessions were $212,000 and $100,000, respectively. At December 31, 2018, the allowance for product returns and the allowance for price concessions were $144,000 and $569,000, respectively. Accounts receivable, net consisted of the following (in thousands): June 30, December 31, 2019 2018 Trade accounts receivable $ 5,584 $ 7,297 Unbilled accounts receivable 592 938 Allowance for accounts receivable (312) (713) Accounts receivable, net $ 5,864 $ 7,522 Concentration of Credit Risk Financial instruments that potentially expose the Company to a concentration of credit risk consist principally of cash and cash equivalents that are held by a financial institution in the United States and accounts receivable. Amounts on deposit with a financial institution may at times exceed federally insured limits. The Company maintains its cash accounts with high credit quality financial institutions and, accordingly, minimal credit risk exists with respect to the financial institutions. Significant customers are those which represent more than 10% of the Company’s total revenue or net accounts receivable balance at each respective balance sheet date. For the purposes of this disclosure, the Company defines “customer” as the entity that is purchasing the products or licenses directly from the Company, which includes the distributors of the Company’s products in addition to end customers that the Company sells to directly. For each significant customer, revenue as a percentage of total revenue and accounts receivable as a percentage of total accounts receivable, net are as follows: Revenue Revenue Accounts Receivable, net Three Months Ended Six Months Ended As of June 30, June 30, June 30, December 31, Customers 2019 2018 2019 2018 2019 2018 Customer A 23 % * 16 % * 40 % 23 % Customer B 13 % * 12 % * * * Customer C 12 % 14 % 12 % 14 % * * Customer D 11 % * 13 % * * * Customer E * * * 20 % * * Customer F * 19 % * 13 % * * Customer G * * * * 11 % 21 % Customer H * * * * * 11 % Customer I * * * * * 11 % * Fair Value of Financial Instruments Fair value is defined as an exit price, representing the amount that would be received to sell an asset, or paid to transfer a liability, in an orderly transaction between market participants. The framework for measuring fair value provides a three-tier hierarchy prioritizing inputs to valuation techniques used in measuring fair value as follows: Level 1— Observable inputs such as quoted prices for identical assets or liabilities in active markets; Level 2— Inputs, other than quoted prices for identical assets or liabilities in active markets, which are observable either directly or indirectly; and Level 3— Unobservable inputs in which there is little or no market data requiring the reporting entity to develop its own assumptions The carrying value of accounts receivable, accounts payable, and other accruals readily convertible into cash approximate fair value because of the short-term nature of the instruments. As of June 30, 2019, based on Level 2 inputs and the borrowing rates available to the Company for loans with similar terms and consideration of the Company’s credit risk, the carrying value of the Company’s variable interest rate debt, excluding unamortized debt issuance costs, approximates fair value. The Company’s financial instruments consist of Level 1 assets. Where quoted prices are available in an active market, securities are classified as Level 1. Level 1 assets consist of highly liquid money market funds that are included in cash equivalents. The following tables sets forth the fair value of the Company’s financial assets measured at fair value on a recurring basis (in thousands): June 30, 2019 Level 1 Level 2 Level 3 Total Assets: Money market funds $ 15,417 $ — $ — $ 15,417 Total assets measured at fair value $ 15,417 $ — $ — $ 15,417 December 31, 2018 Level 1 Level 2 Level 3 Total Assets: Money market funds $ 23,478 $ — $ — $ 23,478 Total assets measured at fair value $ 23,478 $ — $ — $ 23,478 Leases The Company leases office, lab, manufacturing space and equipment in various locations with initial lease terms of up to five years. These leases require monthly lease payments that may be subject to annual increases throughout the lease term. The terms of these leases also include renewal options at the election of the Company to renew or extend the lease for a range of an additional two to five years. These optional periods have not been considered in the determination of the right-of-use-assets (ROU) or lease liabilities associated with these leases as the Company did not consider it reasonably certain it would exercise the options. The Company determines if an arrangement is a lease at inception. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. The classification of the Company's leases as operating or finance leases along with the initial measurement and recognition of the associated ROU assets and lease liabilities is performed at the lease commencement date. The measurement of lease liabilities is based on the present value of future lease payments over the lease term. The Company’s uses its incremental borrowing rate, based on the information available at commencement date, to determine the present value of lease payments when its leases do not provide an implicit rate. The Company uses the implicit rate when readily determinable. The ROU asset is based on the measurement of the lease liability, includes any lease payments made prior to or on lease commencement and excludes lease incentives and initial direct costs incurred, as applicable. Lease expense for the Company’s operating leases is recognized on a straight-line basis over the lease term. Amortization expense for ROU assets associated with finance leases is recognized on a straight-line basis over the shorter of the useful life of the asset or the lease term and interest expense associated with finance leases is recognized on the balance of the lease liability using the effective interest method based on the estimated incremental borrowing rate. The Company has lease agreements with lease and non-lease components. The Company has elected to not separate lease and non-lease components for any leases involving real estate and office equipment classes of assets and, as a result, accounts for the lease and non-lease components as a single lease component. The Company will separate lease and non-lease components for any leases involving manufacturing facility classes of assets. Further, the Company elected the short-term lease exception policy, permitting it to not apply the recognition requirements of this standard to leases with terms of 12 months or less (short-term leases) for all classes of assets. As of June 30, 2019, the Company did not have any short-term leases. Operating leases are included in right-of-use assets, lease liabilities, and lease liabilities, net of current portion in the Company’s balance sheet. Finance leases are included in property and equipment, other current liabilities, and other long-term liabilities in the Company’s balance sheet. Stock-based Compensation Stock-based compensation arrangements include stock option grants and restricted stock unit (RSU) awards under the Company’s equity incentive plans, as well as shares issued under the Company’s Employee Stock Purchase Plan (ESPP), through which employees may purchase the Company’s common stock at a discount to the market price. The Company measures its stock option grants made to employees based on the estimated fair value of the options as of the grant date using the Black-Scholes option-pricing model. Stock-based compensation expense is recognized over the requisite service period using the straight-line method. The Company has made an accounting policy election to account for forfeitures as they occur, rather than estimating expected forfeitures at the time of the grant. Stock-based compensation expense for options granted to non-employees as consideration for services received is measured on the date of performance at the fair value of the consideration received or the fair value of the equity instruments issued, using the Black-Scholes option-pricing model, whichever can be more reliably measured. Compensation expense for options granted to non-employees is recognized as the underlying options vest. The Company has made an accounting policy election to account for forfeitures as they occur, rather than estimating expected forfeitures at the time of the grant. In addition, the Company made an accounting policy election to use the contractual term as the expected term rather than estimating the expected term. Recently Adopted Pronouncements In February 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2016 02, Leases (Topic 842), which establishes a comprehensive new lease accounting model. The new standard: (a) clarifies the definition of a lease; (b) requires a dual approach to lease classification similar to current lease classifications; and (c) causes lessees to recognize leases on the balance sheet as a lease liability with a corresponding ROU asset for leases with a lease-term of more than 12 months. This ASU is effective for fiscal years and interim periods within those years beginning after December 15, 2018. In July 2018, the FASB issued ASU 2018-10, Codification Improvements to Topic 842 Leases and ASU No. 2018-11, Leases (Topic 842) Targeted Improvements. ASU 2018-10 clarifies how to apply certain aspects of ASU 2016-02. The Company adopted this standard on January 1, 2019, using the modified retrospective method. The comparative information has not been restated and continues to be reported under the accounting standards in effect for those periods. Topic 842 permits the application of certain practical expedients, of which the Company elected the “package of three” expedient, that eliminated the requirements to reassess prior conclusions about lease identification, lease classification, and initial direct costs. Further, the Company elected the short-term lease exception policy, permitting it to not apply the recognition requirements of this standard to short-term leases. Upon adoption of Topic 842, on January 1, 2019, the Company recorded an operating lease ROU asset of $3.6 million, operating lease liabilities of $4.0 million, and derecognized the deferred rent liability of $390,000. The accounting for the Company’s finance leases remained substantially unchanged. In June 2018, the FASB issued ASU No. 2018-07, Compensation-Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting. ASU 2018-07 is intended to reduce the cost and complexity and to improve financial reporting for nonemployee share-based payments. The ASU expands the scope of Topic 718, (which currently only includes share-based payments to employees) to include share-based payments issued to nonemployees for goods or services. Consequently, the accounting for share-based payments to nonemployees and employees will be substantially aligned. The standard is effective for fiscal years beginning after December 15, 2018, including interim periods within that fiscal year. Early adoption is permitted, but no earlier than a company’s adoption date of Topic 606. The Company adopted this standard on January 1, 2019 and the impact of its adoption on the Company’s financial statements was not material. Recently Issued Pronouncements In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which amends the incurred loss impairment methodology in current GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. ASU 2016-13 is effective for annual reporting periods, and interim periods within those years, beginning after December 15, 2019, and requires a cumulative effect adjustment to the balance sheet as of the beginning of the first reporting period in which the guidance is effective. In April 2019, the FASB issued ASU No. 2019-04, Codification Improvements Financial Instruments-Credit Losses (Topic 326). The new ASU provides narrow-scope amendments to help apply ASU No. 2016-13. The Company is evaluating the impact of the adoption of ASU 2016-13 on its financial statements.

Revenue

Revenue	6 Months Ended
	Jun. 30, 2019
Revenue
Revenue	3. Revenue The Company sells the majority of its products to its distributors, but also recognizes revenue under licensing and royalty agreements. The following table presents the Company’s revenues disaggregated by sales channel (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Distributor $ 5,564 $ 8,386 $ 12,749 $ 16,531 Non-distributor 3,082 2,379 5,923 9,087 Total revenue $ 8,646 $ 10,765 $ 18,672 $ 25,618 The following table presents the Company’s revenues disaggregated by timing of recognition (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Point in time $ 8,180 $ 9,644 $ 17,631 $ 24,116 Over time 466 1,121 1,041 1,502 Total revenue $ 8,646 $ 10,765 $ 18,672 $ 25,618 The following table presents the Company’s revenues disaggregated by type (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Product sales $ 8,003 $ 9,449 $ 17,026 $ 18,814 License fees — — — 5,000 Royalties 177 195 605 302 Other revenue 466 1,121 1,041 1,502 Total revenue $ 8,646 $ 10,765 $ 18,672 $ 25,618 The Company recognizes revenue in three primary geographic regions: North America; Europe, Middle East and Africa (EMEA); and Asia-Pacific and Japan (APJ). The following table presents the Company’s revenues disaggregated by the geographic region to which the product is delivered or licensee is located (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 North America $ 3,528 $ 2,379 $ 5,717 $ 4,110 EMEA 2,094 2,096 4,728 5,147 APJ 3,024 6,290 8,227 16,361 Total revenue $ 8,646 $ 10,765 $ 18,672 $ 25,618

Balance Sheet Components

Balance Sheet Components	6 Months Ended
	Jun. 30, 2019
Balance Sheet Components
Balance Sheet Components	4. Balance Sheet Components Inventory Inventory consisted of the following (in thousands): June 30, December 31, 2019 2018 Raw materials $ 38 $ 288 Work-in-process 6,501 6,759 Finished goods 2,425 2,050 Total inventory $ 8,964 $ 9,097 Accrued Liabilities Accrued liabilities consisted of the following (in thousands): June 30, December 31, 2019 2018 Accrued payroll-related expenses $ 785 $ 1,558 Accrued joint development agreement expenses 1,190 661 Accrued inventory 812 1,678 Deferred rent — 390 Other 917 714 Total accrued liabilities $ 3,704 $ 5,001

Leases

Leases	6 Months Ended
	Jun. 30, 2019
Leases
Leases	5. Leases During 2017, the Company entered into an operating lease for 27,974 square feet of office space for its corporate headquarters located in Chandler, Arizona, that expires in January 2022. The Company has the option to renew the lease through August 2024; however, the Company does not consider it reasonably certain it will exercise the renewal option. The Company leases office and lab space for its design facility located in Austin, Texas, under an operating lease that expires in January 2022. The Company has the option to renew the lease for an additional five years; however, the Company does not consider it reasonably certain it will exercise the renewal option. The Company has another operating lease for its Arizona manufacturing facility, which includes office and fabrication space. This lease is cancellable upon 24 months’ notice by either of the parties and expires in January 2021. The undiscounted future non-cancellable lease payments under the Company’s leases were as follows (in thousands): As of June 30, 2019 Operating Leases Finance Lease Total 2019 (remaining six months) $ 857 $ 5 $ 862 2020 1,736 10 1,746 2021 859 — 859 2022 50 — 50 Total undiscounted lease payments 3,502 15 3,517 Less: Present value adjustment (208) — (208) Total lease liability 3,294 15 3,309 Less: Current portion of lease liability (1,573) (10) (1,583) Total lease liability, net of current portion $ 1,721 $ 5 $ 1,726 As determined under ASC 840, the future minimum rental commitments under the Company’s operating leases at December 31, 2018 were as follows (in thousands): Year Ending December 31, Amount 2019 $ 1,645 2020 1,701 2021 846 2022 47 Total minimum lease payments $ 4,239 Other information related to the Company's lease liabilities was as follows: As of June 30, 2019 Operating leases Finance lease Weighted-average remaining lease term (years) Weighted-average discount rate % % Lease costs for the Company’s operating leases were $401,000 and $420,000 for the three months ended June 30, 2019 and 2018 respectively, and $800,000 and $851,000, for the six months ended June 30, 2019 and 2018 respectively. Variable lease payments for operating leases were immaterial for the three and six months ended June 30, 2019 and 2018. Lease costs for the Company’s finance lease were immaterial for the three and six months ended June 30, 2019 and 2018.

Debt

Debt	6 Months Ended
	Jun. 30, 2019
Debt
Debt	6. Debt 2017 Credit Facility On May 4, 2017, the Company entered into a Loan and Security Agreement with Silicon Valley Bank (2017 Credit Facility) for a $12.0 million term loan. The term loan provided for interest at a floating rate equal to the prime rate minus 0.75%. The term loan provided for a period of interest-only payments through April 30, 2018, followed by fixed principal and interest payments based on a 24-month amortization schedule. An end of term fee of 6% of the amount borrowed must be made when the loan is prepaid or repaid, whether at maturity or as a result of a prepayment or acceleration or otherwise. On July 6, 2018, the Company entered into the First Amendment to the 2017 Credit Facility (the First Amendment). The First Amendment extended the period of interest-only payments through December 31, 2018, followed by fixed principal and interest payments based on either a 24-month or a 36-month amortization schedule if the Company achieves certain milestones. The Company determined it would not meet the milestones, therefore, the 2017 Credit Facility is based on a 24-month amortization schedule and matures in December 2020. The 2017 Credit Facility provides for interest at a floating rate equal to the prime rate minus 0.75%. As of June 30, 2019, the interest rate was 4.75%. The terms of the First Amendment included the refund of $1.0 million in principal payments previously made by the Company. An end of term fee of 7% of the amount borrowed must be made when the loan is prepaid or repaid, whether at maturity or as a result of a prepayment or acceleration or otherwise. The additional payment is being accreted using the effective interest method. As of June 30, 2019, the effective interest rate under the 2017 Credit Facility was 7.77%. In January 2019 and June 2019, the Company entered into the Second Amendment and the Third Amendment to the 2017 Credit Facility, respectively, which primarily modified the financial covenants under the 2017 Credit Facility. The Company is permitted to make voluntary prepayments of the 2017 Credit Facility with a prepayment fee, calculated as of the effective date of the First Amendment, equal to (i) $240,000 during the first 12 months and (ii) $120,000 if prepaid in months 13-24. The Company is required to make mandatory prepayments of the outstanding loan upon the acceleration by lender following the occurrence of an event of default, along with a payment of the end of term fee, the prepayment fee and any other obligations that are due and payable at the time of prepayment. In the event of default, the interest rate in effect will increase by 5.0% per annum. In conjunction with the First Amendment, outstanding warrants held by SVB to purchase 9,229 shares of the Company’s common stock at $26.00 per share were cancelled. The Company subsequently issued a warrant to SVB for the purchase of 9,375 shares of the Company’s common stock at an exercise price of $8.91 per share. The warrant can be exercised at any time and expires five years after the date of issuance. The Company estimated the fair value of the warrant as $43,000 on the date of issuance using the Black-Scholes option pricing model. The warrant was recorded as a discount to the debt and will be amortized into interest expense over the remaining term of the loan using the effective interest method. Security for the 2017 Credit Facility includes all of the Company’s assets except for intellectual property. The Company is required to comply with certain covenants under the 2017 Credit Facility, including requirements to maintain a minimum liquidity ratio, meet certain revenue targets, and restrictions on certain actions without the consent of the lender, such as limitations on its ability to engage in mergers or acquisitions, sell assets, enter into transactions involving related parties, incur indebtedness or grant liens or negative pledges on its assets, make loans or make other investments. Under these covenants, the Company is prohibited from paying cash dividends with respect to its capital stock. The Company was in compliance with all covenants at June 30, 2019. The 2017 Credit Facility contains a material adverse effect clause which provides that an event of default will occur if, among other triggers, an event occurs that could reasonably be expected to result in a material adverse effect on the Company’s business, operations or condition, or on the Company’s ability to perform its obligations under the term loan. As of June 30, 2019, management does not believe that it is probable that the clause will be triggered within the next 12 months, and therefore the term loan is classified as long-term. The carrying value of the Company’s 2017 Credit Facility at June 30, 2019 was as follows (in thousands): Current Long-Term Portion Debt Total Credit Facility $ 6,000 $ 3,840 $ 9,840 Unamortized debt discounts (23) (198) (221) Net carrying value $ 5,977 $ 3,642 $ 9,619 The carrying value of the Company’s 2017 Credit Facility at December 31, 2018 was as follows (in thousands): Current Long-Term Portion Debt Total Credit Facility $ 6,000 $ 6,840 $ 12,840 Unamortized debt discounts (33) (341) (374) Net carrying value $ 5,967 $ 6,499 $ 12,466 The table below includes the principal repayments due under the 2017 Credit Facility (in thousands): Principal Repayments as of June 30, 2019 2019 (remaining six months) $ 3,000 2020 6,840 Total principal repayments $ 9,840

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2019
Stock-Based Compensation
Stock-Based Compensation	7. Stock-Based Compensation The following table summarizes the stock option and award activity for the six months ended June 30, 2019: Options Outstanding Weighted- Weighted- Options and Average Average Awards Exercise Remaining Aggregate Available for Number of Price Per Contractual Intrinsic Grant Options Share Life (years) Value (In thousands) Balance—December 31, 2018 764,145 1,475,299 $ 7.60 7.8 $ 284 Authorized 512,864 — — RSUs granted (141,750) — — RSUs cancelled/forfeited 9,000 — — Options granted (530,250) 530,250 $ 6.68 Options exercised — (4,188) $ 4.88 $ 12 Options cancelled/forfeited 124,269 (127,798) $ 8.83 Balance—June 30, 2019 738,278 1,873,563 $ 7.26 8.1 $ 556 Options exercisable—June 30, 2019 804,998 $ 6.95 6.9 $ 496 The total grant date fair value of options vested was $516,000 and $545,000 during the three months ended June 30, 2019 and 2018, respectively, and $1.2 million and $922,000 during the six months ended June 30, 2019 and 2018, respectively. The weighted-average grant date fair value of employee options granted was $4.34 and $4.14 per share during the three months ended June 30, 2019 and 2018, respectively, and $4.07 and $4.56 per share during the six months ended June 30, 2019 and 2018, respectively. 2016 Employee Stock Purchase Plan In January 2019, there was an increase of 170,955 shares reserved for issuance under the Company’s Employee Stock Purchase Plan (ESPP). The Company had 417,939 shares available for future issuance under the Company’s ESPP as of June 30, 2019. Employees purchased 22,405 shares for $130,000 during the three and six months ended June 30, 2019. Employees purchased 20,057 shares for $137,000 during the three and six months ended June 30, 2018. Modification of Stock Awards In February 2018, the Company modified the terms of 400,000 vested and unvested stock option awards granted to the Chief Executive Officer, by reducing their exercise price from $16.25 per share to $7.64 per share. There was no change to any of the other terms of the option awards. The modification resulted in an incremental value of $600,000 being allocated to the options, of which $63,000 was recognized to expense immediately based on options that were vested at the time of the modification. The remaining incremental value of $537,000 attributable to unvested options will be recognized over the remaining vesting term through September 2021. Restricted Stock Units The following table summarizes Restricted Stock Units (RSUs) activity for the six months ended June 30, 2019: RSUs Outstanding Weighted- Average Number of Grant Date Restricted Stock Fair Value Per Units Share Balance—December 31, 2018 93,560 $ 8.38 Granted 141,750 6.79 Vested (29,241) 8.40 Cancelled/forfeited (9,000) 7.86 Balance—June 30, 2019 197,069 $ 7.25 The fair value of RSUs is determined on the date of grant based on the market price of the Company’s common stock on that date. As of June 30, 2019, there was $1.3 million of unrecognized stock-based compensation expense related to RSUs to be recognized over a weighted-average period of 2.8 years. Stock-based Compensation Expense The Company recognized stock-based compensation expense from awards granted to employees and non-employees under its equity incentive plans and from its ESPP as follows, excluding amounts related to GLOBALFOUNDRIES, Inc. (GF) (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Research and development $ 161 $ 138 $ 308 $ 246 General and administrative 556 466 1,065 899 Sales and marketing 81 113 129 197 Total $ 798 $ 717 $ 1,502 $ 1,342 As of June 30, 2019, there was $5.5 million of total unrecognized compensation expense related to unvested options which is expected to be recognized over a weighted-average period of 2.7 years. Compensation cost capitalized within inventory at December 31, 2019 and 2018 was not material.

Significant Agreements

Significant Agreements	6 Months Ended
	Jun. 30, 2019
Significant Agreements
Significant Agreements	8. Significant Agreements GLOBALFOUNDRIES, Inc. Joint Development Agreement On October 17, 2014, the Company entered into a Joint Development Agreement (JDA) with GF, for the joint development of the Company’s Spin Transfer Torque MRAM (STT-MRAM) technology. In October 2018, the Company entered into the Third Amendment to the JDA with GF, which extended the term of the JDA until December 2019. The JDA also states that the specific terms and conditions for the production and supply of the developed STT-MRAM technology would be pursuant to a separate manufacturing agreement entered into between the parties. Under the current JDA extension terms, each party licenses its relevant intellectual property to the other party. For certain jointly developed works, the parties have agreed to follow an invention allocation procedure to determine ownership. In addition, GF possesses the exclusive right to manufacture the Company’s discrete and embedded STT-MRAM devices developed pursuant to the agreement until the earlier of three years after the qualification of the MRAM device for a particular technology node or four years after the completion of the relevant statement of work under which the device was developed. For the same exclusivity period associated with the relevant device, GF agreed not to license intellectual property developed in connection with the JDA to named competitors of the Company. Generally, unless otherwise specified in the agreement or a statement of work, the Company and GF share project costs, which do not include personnel or production qualification costs, under the JDA. If GF manufactures, sells or transfers to customers wafers containing production quantified STT-MRAM devices that utilize certain design information, GF will be required to pay the Company a royalty. The Company incurred project costs of $440,000 and $2.3 million for the three months ended June 30, 2019 and 2018 respectively and $1.2 million and $4.4 million for the six months ended June 30, 2019 and 2018 respectively, which were recognized in research and development expense. The Company entered into a Statement of Work (SOW) and an Amendment to the SOW, under the JDA with GF effective August 2016 and June 2018, respectively. The Company is entitled to revenues under the SOW and its Amendment upon delivery and acceptance of product. The Company did not recognize any revenue from GF during the three and six months ended June 30, 2019 and recognized revenue from GF of $500,000 during the three and six months ended June 30, 2018. On October 21, 2014, GF participated, along with other investors, in the Company’s Series B redeemable convertible preferred stock financing and purchased 192,307 shares at $26.00 per share. Contemporaneously, the Company sold 461,538 shares of its common stock to GF at a discounted price of $0.00026 per share. The common shares vest upon the achievement of a goal as set forth in the Statement of Work #1 (the SOW) under the JDA. The unvested common shares are subject to repurchase by the Company, if the JDA is terminated for any reason, for a one-year period after such termination, at a price that is the lower of the original price paid by GF or the fair value of the Company’s common stock as of the date of repurchase. The Company has determined that the issuance of these shares of common stock to GF represents compensation for services to be provided under the JDA. Accordingly, the shares are accounted for similar to a stock award granted to a non-employee of the Company and are remeasured to their fair value as they vest. A total of 211,538 shares of common stock became vested on August 21, 2016, the designated Initial Measurement Date. The remaining shares vested on a monthly basis through October 21, 2018. The Company recognized non-cash compensation expense of $225,000 and $462,000 during the three and six months ended June 30, 2018, in research and development expense related to the vesting of the shares of common stock. As of December 31, 2018, all shares issued to GF were fully vested. Silterra Malaysia Sdn. Bhd. Joint Collaboration Agreement In September 2018, the Company entered into a Joint Collaboration Agreement (JCA) with Silterra Malaysia Sdn. Bhd. (Silterra), and another third party. The JCA will create additional manufacturing capacity for the Company’s Toggle MRAM products. Initial production is expected to start in 2020. Under the JCA the Company will pay non-recurring engineering costs of $1.0 million. As of June 30, 2019, the Company has paid $400,000 of JCA costs. There were no JCA costs paid for during the three and six months ended June 30, 2019. License Agreement In March 2018, the Company entered into a global cross-license agreement with a customer pursuant to which the Company granted a worldwide, non-exclusive, non-transferable, irrevocable, royalty-bearing license under the Company’s patents to use, sell, import and export the Company’s products. Under the cross-license agreement, the Company received a non-refundable license fee and is entitled to annual royalty payments based upon low single digits of the average selling price of products covered under the license agreement. The license was transferred to the customer and the Company recognized the non-refundable license fee during the six months ended June 30, 2018. The cross-license agreement will remain in effect until the licensed patents have expired, been abandoned, or ruled invalid.

Net Loss Per Common Share

Net Loss Per Common Share	6 Months Ended
	Jun. 30, 2019
Net Loss Per Common Share
Net Loss Per Common Share	9. Net Loss Per Common Share The following table sets forth the computation of basic and diluted net loss per share (in thousands, except share and per share amounts): Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Numerator: Net loss $ (3,670) $ (7,369) $ (7,926) $ (8,646) Denominator: Weighted-average common shares outstanding 17,137,338 16,689,677 17,117,777 15,786,043 Less: weighted-average unvested common shares subject to repurchase — (54,416) — (68,795) Weighted-average common shares outstanding used to calculate net loss per common share, basic and diluted 17,137,338 16,635,261 17,117,777 15,717,248 Net loss per common share, basic and diluted $ (0.21) $ (0.44) $ (0.46) $ (0.55) The following outstanding shares of potentially dilutive securities have been excluded from diluted net loss per common share for the periods presented, because their inclusion would be anti-dilutive: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Options to purchase common stock 1,873,563 1,696,187 1,873,563 1,696,187 Restricted stock units 197,069 89,230 197,069 89,230 Common stock subject to repurchase — 38,462 — 38,462 Common stock warrants 27,836 27,690 27,836 27,690 Total 2,098,468 1,851,569 2,098,468 1,851,569

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2019
Subsequent Events
Subsequent Events	10. Subsequent Events In August 2019, the Company executed an Amended and Restated Loan and Security Agreement (the 2019 Credit Facility), which amended and restated the 2017 Credit Facility, providing for a formula revolving line of credit (Line of Credit) and a term loan (2019 Term Loan) with Silicon Valley Bank to refinance in full the outstanding principal balance of $8.0 million under the 2017 Credit Facility. The Company paid the final payment of $0.8 million, which was due upon repayment of the 2017 Credit Facility. The Line of Credit allows for a maximum draw of $5.0 million, subject to a formula borrowing base, has a two year term and bears interest at a floating rate equal to the Wall Street Journal (WSJ) prime rate plus 1.5%, per annum, subject to a floor of 6.75%. The Line of Credit provides for a commitment fee of 1.6% of the maximum availability of the Line of Credit, due upon closing, and a termination fee equal to 1% of the maximum availability under the Line of Credit, which is due in case of a termination of the Line of Credit prior to the scheduled maturity date. The Company drew $2.0 million at execution to pay off a portion of the outstanding balance of the 2017 Credit Facility, and $3.0 million remains available under the Line of Credit, subject to borrowing base availability. The 2019 Term Loan provides for a $6.0 million term loan funded in full at closing, with a term of 42 months, and a 12-month interest only period followed by 30 months of equal principal payments, plus accrued interest. The 2019 Term Loan bears interest at a floating rate equal to the WSJ prime rate minus 0.75%, subject to a floor of 4.75%. A final payment of 7% of the original principal amount of the 2019 Term Loan must be made when the 2019 Term Loan is prepaid or repaid, whether at maturity or as a result of a prepayment or acceleration or otherwise. The 2019 Term Loan has a prepayment fee equal to 2% of the total commitment, which is due only if the 2019 Term Loan is prepaid prior to the scheduled maturity date for any reason. The 2019 Credit Facility contains a financial covenant, which requires the Company to maintain a minimum liquidity ratio. The obligations under the 2019 Credit Facility are secured by a first priority perfected security interest in the Company’s assets excluding intellectual property. In conjunction with entering into the 2019 Credit Facility, on August 5, 2019, the Company and SVB amended and restated the warrant issued to SVB in connection with the First Amendment, which was a warrant to purchase 9,375 shares of the Company’s common stock at $8.91 per share, to add an option by SVB to put the warrant back to the Company for $50,000 upon expiration or a liquidity event, to be prorated if SVB exercises a portion of the warrant. The warrant expires on July 6, 2023.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2019
Summary of Significant Accounting Policies
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (GAAP) and applicable rules and regulations of the Securities and Exchange Commission (SEC) regarding interim financial reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by GAAP have been condensed or omitted, and accordingly the balance sheet as of December 31, 2018 has been derived from the audited financial statements at that date but does not include all of the information required by GAAP for complete financial statements. These unaudited interim condensed financial statements have been prepared on the same basis as the Company’s annual financial statements and, in the opinion of management, reflect all adjustments (consisting only of normal recurring adjustments) that are necessary for a fair statement of the Company’s financial information. The results of operations for the three and six months ended June 30, 2019 are not necessarily indicative of the results to be expected for the year ending December 31, 2019 or for any other interim period or for any other future year. The accompanying condensed financial statements and related financial information should be read in conjunction with the audited financial statements and the related notes thereto for the year ended December 31, 2018, included in the Company’s Annual Report on Form 10-K filed with the SEC.
Use of Estimates	Use of Estimates The preparation of the condensed financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the condensed financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, management evaluates its estimates, including those related to revenue recognition, fair value of assets and liabilities, inventory, product warranty reserves, income taxes, and stock-based compensation. The Company believes its estimates and assumptions are reasonable; however, actual results may differ from the Company’s estimates.
Accounts receivable, net	Accounts receivable, net The Company estimates credits to distributors based on the historical rate of credits provided to distributors relative to sales. At June 30, 2019, the allowance for product returns and the allowance for price concessions were $212,000 and $100,000, respectively. At December 31, 2018, the allowance for product returns and the allowance for price concessions were $144,000 and $569,000, respectively. Accounts receivable, net consisted of the following (in thousands): June 30, December 31, 2019 2018 Trade accounts receivable $ 5,584 $ 7,297 Unbilled accounts receivable 592 938 Allowance for accounts receivable (312) (713) Accounts receivable, net $ 5,864 $ 7,522
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments that potentially expose the Company to a concentration of credit risk consist principally of cash and cash equivalents that are held by a financial institution in the United States and accounts receivable. Amounts on deposit with a financial institution may at times exceed federally insured limits. The Company maintains its cash accounts with high credit quality financial institutions and, accordingly, minimal credit risk exists with respect to the financial institutions. Significant customers are those which represent more than 10% of the Company’s total revenue or net accounts receivable balance at each respective balance sheet date. For the purposes of this disclosure, the Company defines “customer” as the entity that is purchasing the products or licenses directly from the Company, which includes the distributors of the Company’s products in addition to end customers that the Company sells to directly. For each significant customer, revenue as a percentage of total revenue and accounts receivable as a percentage of total accounts receivable, net are as follows: Revenue Revenue Accounts Receivable, net Three Months Ended Six Months Ended As of June 30, June 30, June 30, December 31, Customers 2019 2018 2019 2018 2019 2018 Customer A 23 % * 16 % * 40 % 23 % Customer B 13 % * 12 % * * * Customer C 12 % 14 % 12 % 14 % * * Customer D 11 % * 13 % * * * Customer E * * * 20 % * * Customer F * 19 % * 13 % * * Customer G * * * * 11 % 21 % Customer H * * * * * 11 % Customer I * * * * * 11 % *
Fair Value of Financial Instruments	Fair Value of Financial Instruments Fair value is defined as an exit price, representing the amount that would be received to sell an asset, or paid to transfer a liability, in an orderly transaction between market participants. The framework for measuring fair value provides a three-tier hierarchy prioritizing inputs to valuation techniques used in measuring fair value as follows: Level 1— Observable inputs such as quoted prices for identical assets or liabilities in active markets; Level 2— Inputs, other than quoted prices for identical assets or liabilities in active markets, which are observable either directly or indirectly; and Level 3— Unobservable inputs in which there is little or no market data requiring the reporting entity to develop its own assumptions The carrying value of accounts receivable, accounts payable, and other accruals readily convertible into cash approximate fair value because of the short-term nature of the instruments. As of June 30, 2019, based on Level 2 inputs and the borrowing rates available to the Company for loans with similar terms and consideration of the Company’s credit risk, the carrying value of the Company’s variable interest rate debt, excluding unamortized debt issuance costs, approximates fair value. The Company’s financial instruments consist of Level 1 assets. Where quoted prices are available in an active market, securities are classified as Level 1. Level 1 assets consist of highly liquid money market funds that are included in cash equivalents. The following tables sets forth the fair value of the Company’s financial assets measured at fair value on a recurring basis (in thousands): June 30, 2019 Level 1 Level 2 Level 3 Total Assets: Money market funds $ 15,417 $ — $ — $ 15,417 Total assets measured at fair value $ 15,417 $ — $ — $ 15,417 December 31, 2018 Level 1 Level 2 Level 3 Total Assets: Money market funds $ 23,478 $ — $ — $ 23,478 Total assets measured at fair value $ 23,478 $ — $ — $ 23,478
Leases	Leases The Company leases office, lab, manufacturing space and equipment in various locations with initial lease terms of up to five years. These leases require monthly lease payments that may be subject to annual increases throughout the lease term. The terms of these leases also include renewal options at the election of the Company to renew or extend the lease for a range of an additional two to five years. These optional periods have not been considered in the determination of the right-of-use-assets (ROU) or lease liabilities associated with these leases as the Company did not consider it reasonably certain it would exercise the options. The Company determines if an arrangement is a lease at inception. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. The classification of the Company's leases as operating or finance leases along with the initial measurement and recognition of the associated ROU assets and lease liabilities is performed at the lease commencement date. The measurement of lease liabilities is based on the present value of future lease payments over the lease term. The Company’s uses its incremental borrowing rate, based on the information available at commencement date, to determine the present value of lease payments when its leases do not provide an implicit rate. The Company uses the implicit rate when readily determinable. The ROU asset is based on the measurement of the lease liability, includes any lease payments made prior to or on lease commencement and excludes lease incentives and initial direct costs incurred, as applicable. Lease expense for the Company’s operating leases is recognized on a straight-line basis over the lease term. Amortization expense for ROU assets associated with finance leases is recognized on a straight-line basis over the shorter of the useful life of the asset or the lease term and interest expense associated with finance leases is recognized on the balance of the lease liability using the effective interest method based on the estimated incremental borrowing rate. The Company has lease agreements with lease and non-lease components. The Company has elected to not separate lease and non-lease components for any leases involving real estate and office equipment classes of assets and, as a result, accounts for the lease and non-lease components as a single lease component. The Company will separate lease and non-lease components for any leases involving manufacturing facility classes of assets. Further, the Company elected the short-term lease exception policy, permitting it to not apply the recognition requirements of this standard to leases with terms of 12 months or less (short-term leases) for all classes of assets. As of June 30, 2019, the Company did not have any short-term leases. Operating leases are included in right-of-use assets, lease liabilities, and lease liabilities, net of current portion in the Company’s balance sheet. Finance leases are included in property and equipment, other current liabilities, and other long-term liabilities in the Company’s balance sheet.
Stock-based Compensation	Stock-based Compensation Stock-based compensation arrangements include stock option grants and restricted stock unit (RSU) awards under the Company’s equity incentive plans, as well as shares issued under the Company’s Employee Stock Purchase Plan (ESPP), through which employees may purchase the Company’s common stock at a discount to the market price. The Company measures its stock option grants made to employees based on the estimated fair value of the options as of the grant date using the Black-Scholes option-pricing model. Stock-based compensation expense is recognized over the requisite service period using the straight-line method. The Company has made an accounting policy election to account for forfeitures as they occur, rather than estimating expected forfeitures at the time of the grant. Stock-based compensation expense for options granted to non-employees as consideration for services received is measured on the date of performance at the fair value of the consideration received or the fair value of the equity instruments issued, using the Black-Scholes option-pricing model, whichever can be more reliably measured. Compensation expense for options granted to non-employees is recognized as the underlying options vest. The Company has made an accounting policy election to account for forfeitures as they occur, rather than estimating expected forfeitures at the time of the grant. In addition, the Company made an accounting policy election to use the contractual term as the expected term rather than estimating the expected term.
Recently Adopted Pronouncements and Recently Issued Pronouncements	Recently Adopted Pronouncements In February 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2016 02, Leases (Topic 842), which establishes a comprehensive new lease accounting model. The new standard: (a) clarifies the definition of a lease; (b) requires a dual approach to lease classification similar to current lease classifications; and (c) causes lessees to recognize leases on the balance sheet as a lease liability with a corresponding ROU asset for leases with a lease-term of more than 12 months. This ASU is effective for fiscal years and interim periods within those years beginning after December 15, 2018. In July 2018, the FASB issued ASU 2018-10, Codification Improvements to Topic 842 Leases and ASU No. 2018-11, Leases (Topic 842) Targeted Improvements. ASU 2018-10 clarifies how to apply certain aspects of ASU 2016-02. The Company adopted this standard on January 1, 2019, using the modified retrospective method. The comparative information has not been restated and continues to be reported under the accounting standards in effect for those periods. Topic 842 permits the application of certain practical expedients, of which the Company elected the “package of three” expedient, that eliminated the requirements to reassess prior conclusions about lease identification, lease classification, and initial direct costs. Further, the Company elected the short-term lease exception policy, permitting it to not apply the recognition requirements of this standard to short-term leases. Upon adoption of Topic 842, on January 1, 2019, the Company recorded an operating lease ROU asset of $3.6 million, operating lease liabilities of $4.0 million, and derecognized the deferred rent liability of $390,000. The accounting for the Company’s finance leases remained substantially unchanged. In June 2018, the FASB issued ASU No. 2018-07, Compensation-Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting. ASU 2018-07 is intended to reduce the cost and complexity and to improve financial reporting for nonemployee share-based payments. The ASU expands the scope of Topic 718, (which currently only includes share-based payments to employees) to include share-based payments issued to nonemployees for goods or services. Consequently, the accounting for share-based payments to nonemployees and employees will be substantially aligned. The standard is effective for fiscal years beginning after December 15, 2018, including interim periods within that fiscal year. Early adoption is permitted, but no earlier than a company’s adoption date of Topic 606. The Company adopted this standard on January 1, 2019 and the impact of its adoption on the Company’s financial statements was not material. Recently Issued Pronouncements In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which amends the incurred loss impairment methodology in current GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. ASU 2016-13 is effective for annual reporting periods, and interim periods within those years, beginning after December 15, 2019, and requires a cumulative effect adjustment to the balance sheet as of the beginning of the first reporting period in which the guidance is effective. In April 2019, the FASB issued ASU No. 2019-04, Codification Improvements Financial Instruments-Credit Losses (Topic 326). The new ASU provides narrow-scope amendments to help apply ASU No. 2016-13. The Company is evaluating the impact of the adoption of ASU 2016-13 on its financial statements.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2019
Summary of Significant Accounting Policies
Schedule of accounts receivable net	Accounts receivable, net consisted of the following (in thousands): June 30, December 31, 2019 2018 Trade accounts receivable $ 5,584 $ 7,297 Unbilled accounts receivable 592 938 Allowance for accounts receivable (312) (713) Accounts receivable, net $ 5,864 $ 7,522
Schedule of Revenue and Accounts Receivable for Each Significant Customer	Revenue Revenue Accounts Receivable, net Three Months Ended Six Months Ended As of June 30, June 30, June 30, December 31, Customers 2019 2018 2019 2018 2019 2018 Customer A 23 % * 16 % * 40 % 23 % Customer B 13 % * 12 % * * * Customer C 12 % 14 % 12 % 14 % * * Customer D 11 % * 13 % * * * Customer E * * * 20 % * * Customer F * 19 % * 13 % * * Customer G * * * * 11 % 21 % Customer H * * * * * 11 % Customer I * * * * * 11 % *
Schedule of Fair Value of Financial Assets Measured on Recurring Basis	The following tables sets forth the fair value of the Company’s financial assets measured at fair value on a recurring basis (in thousands): June 30, 2019 Level 1 Level 2 Level 3 Total Assets: Money market funds $ 15,417 $ — $ — $ 15,417 Total assets measured at fair value $ 15,417 $ — $ — $ 15,417 December 31, 2018 Level 1 Level 2 Level 3 Total Assets: Money market funds $ 23,478 $ — $ — $ 23,478 Total assets measured at fair value $ 23,478 $ — $ — $ 23,478

Revenue (Tables)

Revenue (Tables)	6 Months Ended
	Jun. 30, 2019
Revenue
Schedule of disaggregation of revenue	The following table presents the Company’s revenues disaggregated by sales channel (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Distributor $ 5,564 $ 8,386 $ 12,749 $ 16,531 Non-distributor 3,082 2,379 5,923 9,087 Total revenue $ 8,646 $ 10,765 $ 18,672 $ 25,618 The following table presents the Company’s revenues disaggregated by timing of recognition (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Point in time $ 8,180 $ 9,644 $ 17,631 $ 24,116 Over time 466 1,121 1,041 1,502 Total revenue $ 8,646 $ 10,765 $ 18,672 $ 25,618 The following table presents the Company’s revenues disaggregated by type (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Product sales $ 8,003 $ 9,449 $ 17,026 $ 18,814 License fees — — — 5,000 Royalties 177 195 605 302 Other revenue 466 1,121 1,041 1,502 Total revenue $ 8,646 $ 10,765 $ 18,672 $ 25,618 The Company recognizes revenue in three primary geographic regions: North America; Europe, Middle East and Africa (EMEA); and Asia-Pacific and Japan (APJ). The following table presents the Company’s revenues disaggregated by the geographic region to which the product is delivered or licensee is located (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 North America $ 3,528 $ 2,379 $ 5,717 $ 4,110 EMEA 2,094 2,096 4,728 5,147 APJ 3,024 6,290 8,227 16,361 Total revenue $ 8,646 $ 10,765 $ 18,672 $ 25,618

Balance Sheet Components (Table

Balance Sheet Components (Tables)	6 Months Ended
	Jun. 30, 2019
Balance Sheet Components
Schedule of Inventory	Inventory consisted of the following (in thousands): June 30, December 31, 2019 2018 Raw materials $ 38 $ 288 Work-in-process 6,501 6,759 Finished goods 2,425 2,050 Total inventory $ 8,964 $ 9,097
Schedule of Accrued Liabilities	Accrued liabilities consisted of the following (in thousands): June 30, December 31, 2019 2018 Accrued payroll-related expenses $ 785 $ 1,558 Accrued joint development agreement expenses 1,190 661 Accrued inventory 812 1,678 Deferred rent — 390 Other 917 714 Total accrued liabilities $ 3,704 $ 5,001

Leases (Tables)

Leases (Tables)	6 Months Ended
	Jun. 30, 2019
Leases
Schedule of future lease payments	The undiscounted future non-cancellable lease payments under the Company’s leases were as follows (in thousands): As of June 30, 2019 Operating Leases Finance Lease Total 2019 (remaining six months) $ 857 $ 5 $ 862 2020 1,736 10 1,746 2021 859 — 859 2022 50 — 50 Total undiscounted lease payments 3,502 15 3,517 Less: Present value adjustment (208) — (208) Total lease liability 3,294 15 3,309 Less: Current portion of lease liability (1,573) (10) (1,583) Total lease liability, net of current portion $ 1,721 $ 5 $ 1,726 As determined under ASC 840, the future minimum rental commitments under the Company’s operating leases at December 31, 2018 were as follows (in thousands): Year Ending December 31, Amount 2019 $ 1,645 2020 1,701 2021 846 2022 47 Total minimum lease payments $ 4,239
Schedule of supplemental information	As of June 30, 2019 Operating leases Finance lease Weighted-average remaining lease term (years) Weighted-average discount rate % %

Debt (Tables)

Debt (Tables)	6 Months Ended
	Jun. 30, 2019
Debt
Summary of Debt	The carrying value of the Company’s 2017 Credit Facility at June 30, 2019 was as follows (in thousands): Current Long-Term Portion Debt Total Credit Facility $ 6,000 $ 3,840 $ 9,840 Unamortized debt discounts (23) (198) (221) Net carrying value $ 5,977 $ 3,642 $ 9,619 The carrying value of the Company’s 2017 Credit Facility at December 31, 2018 was as follows (in thousands): Current Long-Term Portion Debt Total Credit Facility $ 6,000 $ 6,840 $ 12,840 Unamortized debt discounts (33) (341) (374) Net carrying value $ 5,967 $ 6,499 $ 12,466
Summary of Principal Repayments of Credit Facility	The table below includes the principal repayments due under the 2017 Credit Facility (in thousands): Principal Repayments as of June 30, 2019 2019 (remaining six months) $ 3,000 2020 6,840 Total principal repayments $ 9,840

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2019
Stock-Based Compensation
Summary of Stock Option Activity	Options Outstanding Weighted- Weighted- Options and Average Average Awards Exercise Remaining Aggregate Available for Number of Price Per Contractual Intrinsic Grant Options Share Life (years) Value (In thousands) Balance—December 31, 2018 764,145 1,475,299 $ 7.60 7.8 $ 284 Authorized 512,864 — — RSUs granted (141,750) — — RSUs cancelled/forfeited 9,000 — — Options granted (530,250) 530,250 $ 6.68 Options exercised — (4,188) $ 4.88 $ 12 Options cancelled/forfeited 124,269 (127,798) $ 8.83 Balance—June 30, 2019 738,278 1,873,563 $ 7.26 8.1 $ 556 Options exercisable—June 30, 2019 804,998 $ 6.95 6.9 $ 496
Schedule of Restricted Stock Unit Activity	RSUs Outstanding Weighted- Average Number of Grant Date Restricted Stock Fair Value Per Units Share Balance—December 31, 2018 93,560 $ 8.38 Granted 141,750 6.79 Vested (29,241) 8.40 Cancelled/forfeited (9,000) 7.86 Balance—June 30, 2019 197,069 $ 7.25
Summary of Stock-Based Compensation Expense	The Company recognized stock-based compensation expense from awards granted to employees and non-employees under its equity incentive plans and from its ESPP as follows, excluding amounts related to GLOBALFOUNDRIES, Inc. (GF) (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Research and development $ 161 $ 138 $ 308 $ 246 General and administrative 556 466 1,065 899 Sales and marketing 81 113 129 197 Total $ 798 $ 717 $ 1,502 $ 1,342

Net Loss Per Common Share (Tabl

Net Loss Per Common Share (Tables)	6 Months Ended
	Jun. 30, 2019
Net Loss Per Common Share
Computation of Basic and Diluted Net Loss Per Share	The following table sets forth the computation of basic and diluted net loss per share (in thousands, except share and per share amounts): Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Numerator: Net loss $ (3,670) $ (7,369) $ (7,926) $ (8,646) Denominator: Weighted-average common shares outstanding 17,137,338 16,689,677 17,117,777 15,786,043 Less: weighted-average unvested common shares subject to repurchase — (54,416) — (68,795) Weighted-average common shares outstanding used to calculate net loss per common share, basic and diluted 17,137,338 16,635,261 17,117,777 15,717,248 Net loss per common share, basic and diluted $ (0.21) $ (0.44) $ (0.46) $ (0.55)
Schedule of Potentially Dilutive Securities Excluded from Diluted Net Loss Per Common Share	Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Options to purchase common stock 1,873,563 1,696,187 1,873,563 1,696,187 Restricted stock units 197,069 89,230 197,069 89,230 Common stock subject to repurchase — 38,462 — 38,462 Common stock warrants 27,836 27,690 27,836 27,690 Total 2,098,468 1,851,569 2,098,468 1,851,569

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Accounts Receivable, net (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Accounts receivable
Allowance for product returns	$ 212,000	$ 144,000
Allowance for price concessions	100,000	569,000
Trade accounts receivable	5,584,000	7,297,000
Unbilled accounts receivable	592,000	938,000
Allowance for accounts receivable	(312,000)	(713,000)
Accounts receivable, net	$ 5,864,000	$ 7,522,000

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Schedule of Revenue and Accounts Receivable for Each Significant Customer (Details) - Customer Concentration Risk	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Revenue | Customer A
Concentration risk
Concentration risk percentage	23.00%		16.00%
Revenue | Customer A | Maximum
Concentration risk
Concentration risk percentage		10.00%		10.00%
Revenue | Customer B
Concentration risk
Concentration risk percentage	13.00%		12.00%
Revenue | Customer B | Maximum
Concentration risk
Concentration risk percentage		10.00%		10.00%
Revenue | Customer C
Concentration risk
Concentration risk percentage	12.00%	14.00%	12.00%	14.00%
Revenue | Customer D
Concentration risk
Concentration risk percentage	11.00%		13.00%
Revenue | Customer D | Maximum
Concentration risk
Concentration risk percentage		10.00%		10.00%
Revenue | Customer E
Concentration risk
Concentration risk percentage				20.00%
Revenue | Customer E | Maximum
Concentration risk
Concentration risk percentage	10.00%	10.00%	10.00%
Revenue | Customer F
Concentration risk
Concentration risk percentage		19.00%		13.00%
Revenue | Customer F | Maximum
Concentration risk
Concentration risk percentage	10.00%		10.00%
Revenue | Customer G | Maximum
Concentration risk
Concentration risk percentage	10.00%	10.00%	10.00%	10.00%
Revenue | Customer H | Maximum
Concentration risk
Concentration risk percentage	10.00%	10.00%	10.00%	10.00%
Revenue | Customer I | Maximum
Concentration risk
Concentration risk percentage	10.00%	10.00%	10.00%	10.00%
Accounts Receivable, net | Customer A
Concentration risk
Concentration risk percentage			40.00%		23.00%
Accounts Receivable, net | Customer B | Maximum
Concentration risk
Concentration risk percentage			10.00%		10.00%
Accounts Receivable, net | Customer C | Maximum
Concentration risk
Concentration risk percentage			10.00%		10.00%
Accounts Receivable, net | Customer D | Maximum
Concentration risk
Concentration risk percentage			10.00%		10.00%
Accounts Receivable, net | Customer E | Maximum
Concentration risk
Concentration risk percentage			10.00%		10.00%
Accounts Receivable, net | Customer F | Maximum
Concentration risk
Concentration risk percentage			10.00%		10.00%
Accounts Receivable, net | Customer G
Concentration risk
Concentration risk percentage			11.00%		21.00%
Accounts Receivable, net | Customer H
Concentration risk
Concentration risk percentage					11.00%
Accounts Receivable, net | Customer H | Maximum
Concentration risk
Concentration risk percentage			10.00%
Accounts Receivable, net | Customer I
Concentration risk
Concentration risk percentage					11.00%
Accounts Receivable, net | Customer I | Maximum
Concentration risk
Concentration risk percentage			10.00%

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Schedule of Fair Value of Financial Assets and Liabilities Measured on Recurring Basis (Details) - Recurring - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Fair Value
Total assets measured at fair value	$ 15,417	$ 23,478
Level 1
Fair Value
Total assets measured at fair value	15,417	23,478
Money market funds
Fair Value
Money market funds	15,417	23,478
Money market funds | Level 1
Fair Value
Money market funds	$ 15,417	$ 23,478

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Leases (Details)	6 Months Ended
	Jun. 30, 2019
Leases
Operating lease - existence of option to extend	true
Finance lease - existence of option to extend	true
Minimum
Leases
Operating lease renewal term (in years)	2 years
Finance lease renewal term (in years)	2 years
Maximum
Leases
Operating term of lease (in years)	5 years
Operating lease renewal term (in years)	5 years
Finance term of lease (in years)	5 years
Finance lease renewal term (in years)	5 years

Summary of Significant Accoun_8

Summary of Significant Accounting Policies - Recently issued pronouncements (Details) - USD ($) $ in Thousands	Jan. 01, 2019	Jun. 30, 2019
Recently Issued Pronouncement
Practical expedient - package	true
Right-of-use assets		$ 2,947
Operating leases liabilities		$ 3,294
ASU 2016-02
Recently Issued Pronouncement
Right-of-use assets	$ 3,600
Operating leases liabilities	4,000
Derecognized deferred rent liability	$ 390

Revenue - Disaggregated by Sale

Revenue - Disaggregated by Sales Channel (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue
Revenue	$ 8,646	$ 10,765	$ 18,672	$ 25,618
Distributor
Disaggregation of Revenue
Revenue	5,564	8,386	12,749	16,531
Non-distributor
Disaggregation of Revenue
Revenue	$ 3,082	$ 2,379	$ 5,923	$ 9,087

Revenue - Disaggregated by Timi

Revenue - Disaggregated by Timing of Recognition (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue
Revenue	$ 8,646	$ 10,765	$ 18,672	$ 25,618
Point in time
Disaggregation of Revenue
Revenue	8,180	9,644	17,631	24,116
Over time
Disaggregation of Revenue
Revenue	$ 466	$ 1,121	$ 1,041	$ 1,502

Revenue - Disaggregated by Type

Revenue - Disaggregated by Type (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue
Revenue	$ 8,646	$ 10,765	$ 18,672	$ 25,618
Product sales
Disaggregation of Revenue
Revenue	8,003	9,449	17,026	18,814
License fees
Disaggregation of Revenue
Revenue				5,000
Royalties
Disaggregation of Revenue
Revenue	177	195	605	302
Other revenue
Disaggregation of Revenue
Revenue	$ 466	$ 1,121	$ 1,041	$ 1,502

Revenue - Disaggregated by Geog

Revenue - Disaggregated by Geographic Region (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019USD ($)region	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)region	Jun. 30, 2018USD ($)
Disaggregation of Revenue
Number of primary geographic regions | region	3		3
Revenue	$ 8,646	$ 10,765	$ 18,672	$ 25,618
North America
Disaggregation of Revenue
Revenue	3,528	2,379	5,717	4,110
EMEA
Disaggregation of Revenue
Revenue	2,094	2,096	4,728	5,147
APJ
Disaggregation of Revenue
Revenue	$ 3,024	$ 6,290	$ 8,227	$ 16,361

Balance Sheet Components - Sche

Balance Sheet Components - Schedule of Inventory (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Inventory
Raw materials	$ 38	$ 288
Work-in-process	6,501	6,759
Finished goods	2,425	2,050
Total inventory	$ 8,964	$ 9,097

Balance Sheet Components - Sc_2

Balance Sheet Components - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Accrued liabilities
Accrued payroll-related expenses	$ 785	$ 1,558
Accrued joint development agreement expenses	1,190	661
Accrued inventory	812	1,678
Deferred rent		390
Other	917	714
Total accrued liabilities	$ 3,704	$ 5,001

Leases (Details)

Leases (Details) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)	Dec. 31, 2017ft²	Dec. 31, 2018USD ($)
Future operating lease payments
2019 (remaining six months)	$ 857		$ 857
2020	1,736		1,736
2021	859		859
2022	50		50
Total undiscounted lease payments	3,502		3,502
Less: Present value adjustment	(208)		(208)
Total lease liability	3,294		3,294
Less: Current portion of lease liability	(1,573)		(1,573)
Total lease liability, net of current portion	1,721		1,721
Future finance lease payments
2019 (remaining six months)	5		5
2020	10		10
Total undiscounted lease payments	15		15
Total lease liability	15		15
Less: Current portion of lease liability	(10)		(10)
Total lease liability, net of current portion	5		5
Future lease payments
2019 (remaining six months)	862		862
2020	1,746		1,746
2021	859		859
2022	50		50
Total undiscounted lease payments	3,517		3,517
Less: Present value adjustment	(208)		(208)
Total lease liability	3,309		3,309
Less: Current portion of lease liability	(1,583)		(1,583)
Total lease liability, net of current portion	$ 1,726		$ 1,726
Minimum rental commitments
2019						$ 1,645
2020						1,701
2021						846
2022						47
Total minimum lease payments						$ 4,239
Other lease information
Operating lease weighted-average remaining lease term (years)	2 years 1 month 13 days		2 years 1 month 13 days
Finance lease weighted-average remaining lease term (years)	1 year 5 months 1 day		1 year 5 months 1 day
Operating lease weighted-average discount rate	6.01%		6.01%
Finance lease weighted-average discount rate	3.50%		3.50%
Operating lease costs	$ 401	$ 420	$ 800	$ 851
Previous Headquarters
Leases
Area of operating lease (in sq feet) | ft²					27,974
Office and Lab Space
Leases
Operating lease renewal term (in years)	5 years		5 years
Arizona manufacturing facility
Leases
Period to cancel lease upon notice			24 months

Debt - Credit Facility (Details

Debt - Credit Facility (Details)	Jul. 06, 2018USD ($)payment$ / sharesshares	May 04, 2017USD ($)payment	Jun. 30, 2019USD ($)
2017 Credit Facility
Debt
Loan agreement amount		$ 12,000,000
Interest rate			7.77%
Reimbursement of principal payments			$ 1,000,000
End-of-term fee (as a percent)	7.00%	6.00%
Number of shares the warrant can be converted to | shares	9,375
Warrant exercise price | $ / shares	$ 8.91
Warrant exercise expiration period	5 years
Fair value of warrants	$ 43,000
Increase in rate in the event of default (as a percentage)			5.00%
2017 Credit Facility | Prepayment period - first 12 months
Debt
Prepayment fee			$ 240,000
2017 Credit Facility | Prepayment period - months 13-24
Debt
Prepayment fee			$ 120,000
2017 Credit Facility | Minimum
Debt
Number of interest and principal payments | payment	24	24
2017 Credit Facility | Maximum
Debt
Number of interest and principal payments | payment	36
2017 Credit Facility | Prime Rate
Debt
Interest rate, negative basis spread percentage	0.75%	0.75%
Interest rate			4.75%
SVB Credit Facility
Debt
Number of shares the warrant can be converted to that was cancelled | shares	9,229
Warrant exercise price | $ / shares	$ 26

Debt - Carrying Value (Details)

Debt - Carrying Value (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt
Net carrying value of debt, Current Portion	$ 5,977	$ 5,977
Net carrying value of debt, Long-term debt	3,642	6,509
2017 Credit Facility
Debt
Debt, Current Portion	6,000	6,000
Less: Debt issuance costs, Current Portion	(23)	(33)
Net carrying value of debt, Current Portion	5,977	5,967
Debt, including end of term fee, Long-term debt	3,840	6,840
Less: Unamortized debt discounts, Long-term debt	(198)	(341)
Net carrying value of debt, Long-term debt	3,642	6,499
Total principal amount	9,840	12,840
Less: Discount attributable to warrants, end of term fee and debt issuance costs, Total	(221)	(374)
Net carrying value of debt, Total	$ 9,619	$ 12,466

Debt - Summary of Principal Rep

Debt - Summary of Principal Repayments of 2017 Credit Facility (Details) - 2017 Credit Facility - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt
2019 (remaining six months)	$ 3,000
2020	6,840
Total principal amount	$ 9,840	$ 12,840

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Options and Awards Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
Stock-based compensation
Options and Awards Available for Grant, Outstanding, Beginning balance	764,145
Options and Awards Available for Grant, Options authorized	512,864
Options and Awards Available for Grant, RSUs granted	(141,750)
Options Available for Grant, RSUs cancelled/forfeited	9,000
Options and Awards Available for Grant, Options granted	(530,250)
Options Available for Grant, Options exercised	0
Options and Awards Available for Grant, Options cancelled/forfeited	124,269
Options and Awards Available for Grant, Outstanding, Ending balance	738,278	764,145
Number of Options, Outstanding, Beginning balance	1,475,299
Number of Options, Options granted	530,250
Number of Options, Options exercised	(4,188)
Number of Options, Options cancelled/forfeited	(127,798)
Number of Options, Outstanding, Ending balance	1,873,563	1,475,299
Number of Options, exercisable	804,998
Weighted - Average Exercise Price Per Share, Options outstanding, Beginning balance	$ 7.60
Weighted - Average Exercise Price Per Share, Options granted	6.68
Weighted - Average Exercise Price Per Share, Options exercised	4.88
Weighted - Average Exercise Price Per Share, Options cancelled/forfeited	8.83
Weighted - Average Exercise Price Per Share, Options outstanding, Ending balance	7.26	$ 7.60
Weighted - Average Exercise Price Per Share, Options exercisable	$ 6.95
Weighted - Average Remaining Contractual Life, Options outstanding	8 years 1 month 6 days	7 years 9 months 18 days
Weighted - Average Remaining Contractual Life, Options exercisable	6 years 10 months 24 days
Aggregate Intrinsic Value, Options outstanding	$ 556	$ 284
Aggregate Intrinsic Value, Options exercised	12
Aggregate Intrinsic Value, Options exercisable	$ 496

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details) - USD ($)	1 Months Ended		3 Months Ended				6 Months Ended
	Jan. 31, 2019	Feb. 28, 2018	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Jan. 31, 2018
Share-based Compensation
Total grant date fair value of options vested			$ 516,000		$ 545,000		$ 1,200,000	$ 922,000
Shares available for future issuance (in shares)			738,278				738,278		764,145
Value of share issued			$ 137,000	$ 13,000	723,000	$ 309,000
Weighted-average exercise price (per share)			$ 7.26				$ 7.26		$ 7.60
Number of stock options granted (in shares)							530,250
Options remained outstanding			1,873,563				1,873,563		1,475,299
Stock-based compensation expense			$ 798,000		$ 717,000		$ 1,502,000	$ 1,342,000
Immediate vesting
Share-based Compensation
Incremental modification value		$ 63,000
Remaining vesting
Share-based Compensation
Incremental modification value		$ 537,000
Chief Executive Officer
Share-based Compensation
Number of vested and unvested stock option award modified		400,000
Weighted-average exercise price (per share)		$ 7.64								$ 16.25
Incremental modification value		$ 600,000
Employees
Share-based Compensation
Weighted-average grant date fair value of options granted			$ 4.34		$ 4.14		$ 4.07	$ 4.56
2016 Employee Stock Purchase Plan
Share-based Compensation
Increase in number of shares available for grant	170,955
Shares available for future issuance (in shares)			417,939				417,939
Value of share issued			$ 130,000		$ 137,000		$ 130,000	$ 137,000
Number of shares issued (in shares)			22,405		20,057		22,405	20,057

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Units (Details) $ / shares in Units, $ in Millions	6 Months Ended
	Jun. 30, 2019USD ($)$ / sharesshares
Weighted Average Exercise Price Per Share
Unrecognized stock-based compensation expense | $	$ 5.5
Unrecognized compensation expense, weighted-average period expected to be recognized	2 years 8 months 12 days
Restricted stock units
Number of Restricted Stock Units
Balance, beginning of period | shares	93,560
Granted | shares	141,750
Vested | shares	(29,241)
Cancelled/forfeited | shares	(9,000)
Balance, end of period | shares	197,069
Weighted Average Exercise Price Per Share
Balance, beginning of period (price per share) | $ / shares	$ 8.38
Granted (price per share) | $ / shares	6.79
Vested (price per share) | $ / shares	8.40
Cancelled/forfeited (price per share) | $ / shares	7.86
Balance, end of period (price per share) | $ / shares	$ 7.25
2016 Employee Incentive Plan | Restricted stock units
Weighted Average Exercise Price Per Share
Unrecognized stock-based compensation expense | $	$ 1.3
Unrecognized compensation expense, weighted-average period expected to be recognized	2 years 9 months 18 days

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Share-based compensation expense
Stock-based compensation expense	$ 798	$ 717	$ 1,502	$ 1,342
Unrecognized stock-based compensation expense	5,500		$ 5,500
Unrecognized compensation expense, weighted-average period expected to be recognized			2 years 8 months 12 days
Research and development
Share-based compensation expense
Stock-based compensation expense	161	138	$ 308	246
General and administrative
Share-based compensation expense
Stock-based compensation expense	556	466	1,065	899
Sales and marketing
Share-based compensation expense
Stock-based compensation expense	$ 81	$ 113	$ 129	$ 197

Significant Agreements (Details

Significant Agreements (Details) - USD ($)	Aug. 21, 2016	Oct. 21, 2014	Oct. 17, 2014	Sep. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019
Joint development agreement
Research and development expense					$ 3,519,000	$ 6,773,000		$ 7,517,000	$ 13,253,000
Non-cash compensation expense (income)						225,000			462,000
Common Stock
Joint development agreement
Number of shares sold							3,772,447
Joint Development Agreement | Global Foundries, Inc.
Joint development agreement
Period of possession of exclusive right to manufacture after qualification of device			3 years
Period of possession of exclusive right to manufacture after completion of device development work			4 years
Research and development expense					440,000	2,300,000		1,200,000	4,400,000
Milestone revenue						$ 500,000		0	$ 500,000
Period to Repurchase Shares		1 year
Joint Development Agreement | Global Foundries, Inc. | Common Stock
Joint development agreement
Number of shares sold		461,538
Shares sold, price per share		$ 0.00026
Number of shares of common stock, vested	211,538
Joint Development Agreement | Global Foundries, Inc. | Series B Redeemable Convertible Preferred Stock [Member]
Joint development agreement
Number of shares sold		192,307
Shares sold, price per share		$ 26
Collaborative Agreement | Silterra
Joint development agreement
Non-recurring engineering cost obligation				$ 1,000,000
JCA costs					$ 0			$ 0		$ 400,000

Net Loss Per Common Share - Com

Net Loss Per Common Share - Computation of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
Numerator:
Net loss	$ (3,670)	$ (4,256)	$ (7,369)	$ (1,277)	$ (7,926)	$ (8,646)
Denominator:
Weighted-average common shares outstanding	17,137,338		16,689,677		17,117,777	15,786,043
Less: weighted-average unvested common shares subjected to repurchase			(54,416)			(68,795)
Weighted-average common shares outstanding used to calculate net loss per common share, basic and diluted	17,137,338		16,635,261		17,117,777	15,717,248
Net loss per common share, basic and diluted	$ (0.21)		$ (0.44)		$ (0.46)	$ (0.55)

Net Loss Per Common Share - Sch

Net Loss Per Common Share - Schedule of Potentially Dilutive Securities Excluded from Diluted Net Loss Per Common Share (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Antidilutive Securities
Potentially dilutive securities excluded from diluted net loss per common share	2,098,468	1,851,569	2,098,468	1,851,569
Options to purchase common stock
Antidilutive Securities
Potentially dilutive securities excluded from diluted net loss per common share	1,873,563	1,696,187	1,873,563	1,696,187
Restricted stock units
Antidilutive Securities
Potentially dilutive securities excluded from diluted net loss per common share	197,069	89,230	197,069	89,230
Common stock subject to repurchase
Antidilutive Securities
Potentially dilutive securities excluded from diluted net loss per common share		38,462		38,462
Common stock warrants
Antidilutive Securities
Potentially dilutive securities excluded from diluted net loss per common share	27,836	27,690	27,836	27,690

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Thousands	Aug. 07, 2019	Aug. 05, 2019	Jul. 06, 2018	May 04, 2017	Jul. 31, 2019	Jun. 30, 2019	Dec. 31, 2018
2017 Credit Facility
Subsequent events
Principal amount						$ 9,840	$ 12,840
Loan agreement amount				$ 12,000
Effective interest rate						7.77%
End-of-term fee (as a percent)			7.00%	6.00%
Number of shares the warrant can be converted to			9,375
Warrant exercise price			$ 8.91
2017 Credit Facility | Prime Rate
Subsequent events
Effective interest rate						4.75%
Interest rate, negative basis spread percentage			0.75%	0.75%
Subsequent Events | 2017 Credit Facility
Subsequent events
Principal amount					$ 8,000
Repayment of credit facility	$ 800
Subsequent Events | 2019 Credit Facility
Subsequent events
Number of shares the warrant can be converted to		9,375
Warrant exercise price		$ 8.91
Amount bank could receive if takes the option to put the warrants upon expiration or a liquidity event		$ 50
Subsequent Events | 2019 Credit Facility - Revolving Line Of Credit
Subsequent events
Loan agreement amount	$ 5,000
Agreement term	2 years
Commitment fee (as a percentage)	1.60%
Termination fee (as a percentage)	1.00%
Debt amount	$ 2,000
Remaining availability	$ 3,000
Subsequent Events | 2019 Credit Facility - Revolving Line Of Credit | Prime Rate
Subsequent events
Interest rate, basis spread percentage	1.50%
Subsequent Events | 2019 Credit Facility - Revolving Line Of Credit | Prime Rate | Minimum
Subsequent events
Effective interest rate	6.75%
Subsequent Events | 2019 Credit Facility - Term Loan
Subsequent events
Agreement term	42 months
Prepayment fee (as a percentage)	2.00%
Debt amount	$ 6,000
Number of months of interest only payment	12 months
Number of months of equal principal payments plus accrued interest	30 months
End-of-term fee (as a percent)	7.00%
Subsequent Events | 2019 Credit Facility - Term Loan | Prime Rate
Subsequent events
Interest rate, negative basis spread percentage	0.75%
Subsequent Events | 2019 Credit Facility - Term Loan | Prime Rate | Minimum
Subsequent events
Effective interest rate	4.75%