EXHIBIT 99.1 SUPERTEX, INC. 		PRESS RELEASE FOR IMMEDIATE RELEASE		Contact: Dr. Henry C. Pao May 03, 2004				 President & CEO 					 Tel:	408-222-8888 					 Fax:	408-222-4800 					 Email:	investors@supertex.com 		SUPERTEX REPORTS FOURTH FISCAL QUARTER 		 AND FISCAL YEAR-END RESULTS Sunnyvale, CA (May 03, 2004) - Supertex, Inc. (NASDAQ: SUPX) reported that for the fourth fiscal quarter ended March 31, 2004, net sales decreased 6% to $13,589,000 from $14,530,000 for the same quarter in the prior fiscal year, but increased 4% sequentially from the prior quarter of $13,010,000. Net income for the quarter decreased 74% to $290,000 or $0.02 per share on a diluted basis from $1,098,000 or $0.09 per share for the same quarter of the prior fiscal year and decreased 55% sequentially compared to $647,000 or $0.05 per share for the prior quarter. For the fiscal year ended March 31, 2004, net sales decreased 6% to $51,394,000 from $54,915,000 in the prior year, while net income decreased 24% to $2,159,000 from $2,855,000 in the prior year. Dr. Henry C. Pao, President and CEO, commented, "The fourth quarter of our fiscal year 2004 was characterized by a modest sequential sales growth, in spite of the turns business not being as robust as in the same period last year. According to plan, our sales underwent a product mix change and we reduced our inventory, primarily through write-down, based on this product mix change. Throughout the year we continued to reduce inventories of our older products while planning for tactical inventory of new products with a total net reduction for the year of $2.0 million to a year-end inventory of $12.6 million. Gross margin dropped to 38% compared to 41% in the prior quarter, and improved to 40% from 38% year-over-year despite the continued low production capacity utilization. Cash flow was positive in the quarter. Cash, cash equivalents and short-term investments increased by $11.2 million during the year. Our Research and Development expenses in the quarter went up to $2.64 million dollars or 19.4% of sales. Our sales and marketing expenses increased 14.1% from the prior quarter due to increased activities." He added, "Pre-production orders were received in all our emerging markets of Power-over-Ethernet (POE) ICs, hotswap ICs, LED driver ICs, and high voltage amplifier arrays for Optical-to-Optical telecom applications and our new telecom ringer IC. These 'second stage' orders are encouraging, and combined with a positive book-to-bill ratio, we are bullish on both our top and bottom line growth for our fiscal year 2005, starting with our first fiscal quarter. We have substantial production capacity in wafer fabrication and test in place to easily handle the projected increase in sales." Forward Looking Statements: The industry in which we compete is characterized by extreme rapid changes in technology and frequent new product introductions. We believe that our long-term growth will depend largely on our ability to continue to enhance existing products and to introduce new products and features that meet the continually changing requirements of our customers. All statements contained in this press release that are not historical facts are forward-looking statements. They include our optimism about our continued revenue and earnings growth during fiscal year. These forward-looking statements are made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. They are not guarantees of future performance or events but rather involve a number of risks and uncertainties including, but not limited to, whether our customers experience the demand we anticipate for their products, including products currently in the pre-production stage, which incorporate our products and whether competitors introduce products at lower prices than our products causing price erosion, as well as other risk factors detailed in our Form 8-K, 10-K, and 10-Q filings with the Securities and Exchange Commission. Due to these and other risks, our future actual results could differ materially from those discussed above. These forward-looking statements are based on our goals and objectives and our assumptions about, and assessment of, the future and may or may not prove true. They speak only as to the date of this release, and we undertake no obligation to publicly release updates or revisions to these statements. Conference Call Details The company will host a conference call at 2:30 p.m. PDT (5:30 p.m. EDT) on May 03, 2004, following the earnings release. President and Chief Executive Officer, Dr. Henry C. Pao and Executive Vice President, Richard E. Siegel will present an overview of the fourth fiscal quarter and fiscal 2004 year end financial results, discuss current business conditions and then respond to questions. The call is available live to listen or ask questions by dialing 800-540-0559 (domestic) or 785-832-1508 (toll, international) and ask to be connected to the Supertex Quarterly Earnings Release Call. A recorded replay will be available until 11:59 p.m., May 17, 2004 by dialing 888-274-8336 (domestic) or 402-220-2328 (toll, international). About Supertex Supertex, Inc. is a publicly held mixed signal semiconductor manufacturer, focused in high voltage interface products for use in the telecommunications, networking systems, flat panel displays, medical and industrial electronics industries. Supertex product, corporate and financial information is readily available at www.supertex.com. For further information, contact Dr. Henry C. Pao at Supertex, Inc., 1235 Bordeaux Drive, Sunnyvale, California 94089, 408-222-8888 or visit our Website at http://www.supertex.com. 				SUPERTEX, INC. 		CONSOLIDATED INCOME STATEMENT INFORMATION 				(unaudited) 				 Three-months Ended Fiscal Year Ended 				 March 31,	 March 31, 			 (in thousands, except per share amounts) 				 2004 2003 2004 2003 Net sales		 $ 13,589 $ 14,530 $ 51,394 $ 54,915 Cost of sales 8,423 8,494 30,938 34,103 			 --------- --------- --------- --------- Gross profit 		 5,166 6,036 20,456 20,812 Research and development 2,645 2,366 9,570 9,338 Selling, general and administrative 		 2,617 2,316 9,760 8,722 			 --------- --------- --------- --------- Income from operations (96) 1,354 1,126 2,752 Interest and other income, net 			 516 260 2,003 1,446 			 --------- --------- --------- --------- Income before income taxes 420 1,614 3,129 4,198 Provision for income taxes 130 516 970 1,343 			 ========= ========= ========= ========= Net income $ 290 $ 1,098 $ 2,159 $ 2,855 Net income per share Basic $ 0.02 $ 0.09 $ 0.17 $ 0.23 Diluted $ 0.02 $ 0.09 $ 0.17 $ 0.22 Shares used in per share computation Basic 12,848 12,620 12,758 12,598 Diluted 13,163 12,770 13,051 12,757 				SUPERTEX, INC. 		CONSOLIDATED BALANCE SHEET INFORMATION 				(unaudited) 				 March 31, 2004	 March 31, 2003 		 (in thousands) ASSETS Cash and cash equivalents $ 71,117 $ 60,931 Short term investments 			 5,007 3,945 Accounts receivable, net		 7,667 10,134 Inventories, net 			 12,606 14,582 Deferred income taxes			 4,989 4,030 Other current assets 642 575 				 ---------- ---------- Total current assets 102,028 94,197 Property, plant and equipment 9,731 12,104 Other assets 94 97 Deferred income taxes 944 2,273 				 ---------- ---------- TOTAL ASSETS			 $ 112,797 $ 108,671 				 ========== ========== LIABILITIES Trade accounts payable 		 $ 2,354 $ 3,572 Accrued salaries, wages and employee benefits 7,449 6,784 Other accrued liabilities 481 485 Deferred revenue 3,254 2,001 Income taxes payable 1,485 3,304 				 ----------	 ---------- Total current liabilities 15,023 16,146 				 ---------- ---------- SHAREHOLDERS' EQUITY Common stock 32,134 29,045 Retained earnings 65,640 63,480 				 ---------- ---------- Total shareholders' equity 97,774 92,525 				 ---------- ---------- TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY $ 112,797 $ 108,671 	 ========== ==========