UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C.  20549

FORM 10-K/A

Amendment No.1

(MARK ONE)
(x)	Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 (Fee Required) For the fiscal year ended March 31, 2007
or
(  )	Transition Report Pursuant to Section 13 or 15(d) of the Securities and Exchange Act of 1934 For the transition period from _______ to ________
Commission File No. 0-12718
SUPERTEX, INC.
(Exact name of Registrant as specified in its charter)

California		94-2328535
(State or other jurisdiction of incorporation or organization)		(I.R.S. Employer Identification No.)
1235 Bordeaux Drive, Sunnyvale, California 94089
(Address of principal executive offices)
Registrant's Telephone Number, Including Area Code:  (408) 222-8888
Securities registered pursuant to Section 12(b) of the Act:
Title of each class: Common Stock	Name of each exchange on which registered: Nasdaq Global Select Market
Securities registered pursuant to Section 12(g) of the Act: None
Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.  Yes  o   No  x
Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 of Section 15(d) of the Act.   Yes  o   No  x
Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.Yes  x   No  o
Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (Sec. 229.405 of this chapter) is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. o
Indicate by check mark whether the registrant is an accelerated filer (as defined in Rule 12b-2 of the Act). Check one.    Large accelerated filer o           Accelerated filer x            Non-accelerated filer o            Smaller Reporting Company o
As of September 29, 2006, the last business day of the registrant’s most recently completed second fiscal quarter, there were 13,679,179 shares of the registrant’s common stock outstanding, and the aggregate market value of such shares held by non-affiliates of the registrant was $435,238,896 based on the closing price reported on the NASDAQ National Market on September 29, 2006. Shares of common stock held by officers, directors and other persons who may be deemed “affiliates” of the Registrant have been excluded from this computation.  This determination of affiliate status is not necessarily a conclusive determination for other purposes. The total number of shares outstanding of the Registrant's common stock as of June 11, 2007, was 13,732,728.
Documents Incorporated by Reference:  Part III incorporates by reference portions of the Company's definitive proxy statement for the Annual Meeting of Shareholders held on August 17, 2007 (the "Proxy Statement").

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Explanatory Note

Supertex, Inc. (the “Company”) is filing this Amendment No. 1 to its Annual Report on Form 10-K (“the Amendment”) for the year ended March 31, 2007, which was originally filed on June 14, 2007 (“Original Filing”), to amend in its entirety the Exhibits 32.1, Certification of Chief Executive Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, and Exhibit 32.2,  Certification of Chief Financial Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002. The Exhibits 32.1 and 32.2 of the Original Filing inadvertently included clerical errors on the titles of the exhibits and the dates of the fiscal year.

Pursuant to Rule 12b-15 promulgated under the Securities Exchange Act of 1934, as amended (“Exchange Act”), this Amendment amends in its entirety Item 15(a)(3) of Part IV of the Original Filing and contains new certifications pursuant to Rule 13a-14 promulgated under the Exchange Act. This Amendment contains only the exhibits to the Original Filing that are being amended, and those unaffected parts or exhibits are not included herein. This Amendment continues to speak as of the date of the Original Filing. In this amendment, the Company has not updated the disclosure contained herein to reflect events that have occurred since the filing of the Original Filing. Accordingly, this Amendment should be read in conjunction with the Company’s other filings, if any, made with the United States Securities and Exchange Commission subsequent to the filing of the Original Filing, including the amendment to those filings, if any.

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PART IV

Item 15.   Exhibits and Financial Statement Schedules
(a)	The following documents are filed as part of this form:

3.	Exhibits.
	Exhibit	Exhibit Description
	2.1 (1)	Agreement for purchases and sale of assets by and between Supertex, Inc. and Orbit Semiconductor dated January 16, 1999.
	3.1 (2)	Restated Articles of Incorporation of Registrant filed May 21, 1980.
	3.2 (2)	Certificate of Amendment of Articles of Incorporation filed April 16, 1981.
	3.3 (2)	Certificate of Amendment of Articles of Incorporation filed September 30, 1983.
	3.4 (3)	Certificate of Amendment of Articles of Incorporation filed October 14, 1988.
	3.5 (5)	Bylaws of Registrant, as amended.
	10 (2)	Deferred Compensation Plan (Supplemental Employee Retirement Plan), which became effective January 1, 1996.
	10.2 (1)	Lease Assignment agreement for 71 Vista Montana, San Jose, California, dated February 1, 1999 among Orbit Semiconductor, as assignor, Sobrato Development Companies #871, as landlord, and Supertex, Inc., as assignee.
	10.6 (4)	1991 Stock Option Plan which became effective, with form of stock option agreement.
	10.6a (5)	1991 Stock Option Plan, as amended as of August 4, 1995, with form of stock option agreement.
	10.6b (6)	1991 Stock Option Plan, as amended as of August 6, 1999, with form of stock option agreement.
	10.6c (7)	2000 Employee Stock Purchase Plan.
	10.6d (8)	2001 Stock Option Plan, which became effective, with form of stock option agreement.
	10.7 (2)	Profit Sharing Plan.

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	21.1*	Subsidiary of the Registrant.
	23.1*	Consent of PricewaterhouseCoopers LLP, Independent Registered Public Accounting Firm.
	24.1*	Power of Attorney.
	31.1*	Certification of Chief Executive Officer pursuant to Securities Exchange Act Rules 13a-14(a) and 15d-14(a), as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
	31.2*	Certification of Chief Financial Officer pursuant to Securities Exchange Act Rules 13a-14(a) and 15d-14(a), as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
	31.3	Certification of Chief Executive Officer pursuant to Securities Exchange Act Rules 13a-14(a) and 15d-14(a), as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
	31.4	Certification of Chief Financial Officer pursuant to Securities Exchange Act Rules 13a-14(a) and 15d-14(a), as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
	32.1	Certification of Chief Executive Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
	32.2	Certification of Chief Financial Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
	(1)	Incorporated by reference to the exhibit of the same number filed with current report on form 8-K dated January 19, 1999.
	(2)	Incorporated by reference to exhibit of same number of Registrant's Registration Statement on Form S-1 (File No. 2-86898), which became effective December 6, 1983.
	(3)	Incorporated by reference to exhibit filed with Quarterly Report on Form 10-Q for period ended October 1, 1988.
	(4)	Incorporated by reference to exhibit filed with Annual Report on Form 10-K for year ended March 31, 1991.
	(5)	Incorporated by reference to exhibit included in Registrant's Registration Statement on Form S-8 (File No. 33-43691) which became effective September 1, 1995.
	(6)	Incorporated by reference to exhibit included in Registrant's Registration Statement on Form S-8 (File No. 33-43691) which became effective September 29, 1999.
	(7)	Incorporated by reference to exhibit included in Registrant's Registration Statement on Form S-8 (File No. 333-47606) which became effective October 6, 2000.
	(8)	Incorporated by reference to Appendix B of the Registrants amended Proxy Statement filed on August 7, 2001 (File No. 000-12718).  Corresponding Registration Statement on Form S-8 (File No. 333-69594) became effective on September 18, 2001.
(b	Exhibits  31.3, 31.4, 32.1 and 32.2 are filed herewith.

_______________

* Previously filed.

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

	Supertex, Inc.
Dated:  October 7, 2008		/s/PHILLIP A. KAGEL
		Phillip A. Kagel
		Vice President of Finance and Chief Financial Officer
		(Principal Financial and Accounting Officer)

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

Signature	Title	Date
/s/ HENRY C. PAO	President, Chief Executive Officer	October 7, 2008
(Henry C. Pao)	(Principal Executive Officer)
/s/ PHILLIP A. KAGEL	Vice President of Finance and Chief Financial Officer	October 7, 2008
(Phillip A. Kagel)	(Principal Financial and Accounting Officer)
/s/ BENEDICT C. K. CHOY *	Senior Vice President, Technology Development	October 7, 2008
(Benedict C. K. Choy)
/s/ W. MARK LOVELESS*	Director	October 7, 2008
(W. Mark Loveless)
/s/ ELLIOTT SCHLAM *	Director	October 7, 2008
(Elliott Schlam)
/s/ MILTON FENG *	Director	October 7, 2008
(Milton Feng)
*By:  /s/ HENRY C. PAO	Attorney-in-fact	October 7, 2008
(Henry C. Pao)

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SUPERTEX, INC.

EXHIBIT INDEX

(The Registrant will furnish to any shareholders who so request a copy of this Annual Report on Form 10-K and any Exhibit listed below, provided that the Registrant may require payment of a reasonable fee not to exceed its expense in furnishing such information. The following exhibits are filed as part of, or incorporated by reference into, this Amendment No. 1 to the Annual Report on Form 10-K.)

Exhibit	Exhibit Description
2.1 (1)	Agreement for purchases and sale of assets by and between Supertex, Inc. and Orbit Semiconductor dated January 16, 1999.
3.1 (2)	Restated Articles of Incorporation of Registrant filed May 21, 1980.
3.2 (2)	Certificate of Amendment of Articles of Incorporation filed April 16, 1981.
3.3 (2)	Certificate of Amendment of Articles of Incorporation filed September 30, 1983.
3.4 (3)	Certificate of Amendment of Articles of Incorporation filed October 14, 1988.
3.5 (5)	Bylaws of Registrant, as amended.
10 (2)	Deferred Compensation Plan (Supplemental Employee Retirement Plan), which became effective January 1, 1996.
10.2 (1)	Lease Assignment agreement for 71 Vista Montana, San Jose, California, dated February 1, 1999 among Orbit Semiconductor, as assignor, Sobrato Development Companies #871, as landlord, and Supertex, Inc., as assignee.
10.6 (4)	1991 Stock Option Plan which became effective, with form of stock option agreement.
10.6a (5)	1991 Stock Option Plan, as amended as of August 4, 1995, with form of stock option agreement.
10.6b (6)	1991 Stock Option Plan, as amended as of August 6, 1999, with form of stock option agreement.
10.6c (7)	2000 Employee Stock Purchase Plan.
10.6d (8)	2001 Stock Option Plan, which became effective, with form of stock option agreement.
10.7 (2)	Profit Sharing Plan.

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21.1*	Subsidiary of the Registrant.
23.1*	Consent of PricewaterhouseCoopers LLP, Independent Registered Public Accounting Firm.
24.1*	Power of Attorney.
31.1*	Certification of Chief Executive Officer pursuant to Securities Exchange Act Rules 13a-14(a) and 15d-14(a), as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
31.2*	Certification of Chief Financial Officer pursuant to Securities Exchange Act Rules 13a-14(a) and 15d-14(a), as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
31.3	Certification of Chief Executive Officer pursuant to Securities Exchange Act Rules 13a-14(a) and 15d-14(a), as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
31.4	Certification of Chief Financial Officer pursuant to Securities Exchange Act Rules 13a-14(a) and 15d-14(a), as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
32.1	Certification of Chief Executive Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
32.2	Certification of Chief Financial Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
(1)	Incorporated by reference to the exhibit of the same number filed with current report on form 8-K dated January 19, 1999.
(2)	Incorporated by reference to exhibit of same number of Registrant's Registration Statement on Form S-1 (File No. 2-86898), which became effective December 6, 1983.
(3)	Incorporated by reference to exhibit filed with Quarterly Report on Form 10-Q for period ended October 1, 1988.
(4)	Incorporated by reference to exhibit filed with Annual Report on Form 10-K for year ended March 31, 1991.
(5)	Incorporated by reference to exhibit included in Registrant's Registration Statement on Form S-8 (File No. 33-43691) which became effective September 1, 1995.
(6)	Incorporated by reference to exhibit included in Registrant's Registration Statement on Form S-8 (File No. 33-43691) which became effective September 29, 1999.
(7)	Incorporated by reference to exhibit included in Registrant's Registration Statement on Form S-8 (File No. 333-47606) which became effective October 6, 2000.
(8)	Incorporated by reference to Appendix B of the Registrants amended Proxy Statement filed on August 7, 2001 (File No. 000-12718).  Corresponding Registration Statement on Form S-8 (File No. 333-69594) became effective on September 18, 2001.
* Previously filed

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 EXHIBIT 31.3

CERTIFICATIONS UNDER RULE 13a-14(a)/l5d-14(a)

I, Henry C. Pao, certify that:

1. I have reviewed this Amendment No. 1 (to Form 10-K) of Supertex, Inc., a California corporation;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report.

Date: October 7, 2008	/s/  HENRY C. PAO
	Henry C. Pao, Ph.D.
	Chief Executive Officer

EXHIBIT 31.4

CERTIFICATIONS UNDER RULE 13a-14(a)/l5d-14(a)

I, Phillip A. Kagel, certify that:

1. I have reviewed this amendment No. 1 (to Form 10-K) of Supertex, Inc., a California corporation;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report.

Date: October 7, 2008	/s/  PHILLIP A. KAGEL
	Phillip A. Kagel
	Vice President of Finance and Chief Financial Officer
	(Principal Financial Officer and Principal Accounting Officer)

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EXHIBIT 32.1

STATEMENT OF CHIEF EXECUTIVE OFFICER UNDER 18 U.S.C. § 1350

I, Henry C. Pao, the chief executive officer of Supertex, Inc., a California corporation (the “Company”), certify pursuant to Section 1350 of Chapter 63 of Title 18 of the United States Code, that to my knowledge:

(i) the Annual Report of the Company on Form 10-K for the period ending March 31, 2007 (the “Report”), fully complies with the requirements of Section 13(a) or 15(d), whichever is applicable, of the Securities Exchange Act of 1934, and

(ii) the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: October 7, 2008	/s/ HENRY C. PAO
	Henry C. Pao, Ph.D.
	Chief Executive Officer

The material contained in this Exhibit 32.1 is not deemed “filed” with the SEC and is not to be incorporated by reference into any filing of the Company under the Securities Act of 1933 or the Securities Exchange Act of 1934, whether made before or after the date hereof and irrespective of any general incorporation language contained in such filing.

EXHIBIT 32.2

STATEMENT OF CHIEF FINANCIAL OFFICER UNDER 18 U.S.C. § 1350

I, Phillip A. Kagel, the vice president of finance and chief financial officer of Supertex, Inc., a California corporation (the “Company”), certify pursuant to Section 1350 of Chapter 63 of Title 18 of the United States Code, that to my knowledge:

(i) the Annual Report of the Company on Form 10-K for the period ending March 31, 2007 (the “Report”), fully complies with the requirements of Section 13(a) or 15(d), whichever is applicable, of the Securities Exchange Act of 1934, and

(ii) the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: October 7, 2008	/s/ PHILLIP A. KAGEL
	Phillip A. Kagel
	Vice President of Finance and Chief Financial Officer
	(Principal Financial Officer and Principal Accounting Officer)

The material contained in this Exhibit 32.2 is not deemed “filed” with the SEC and is not to be incorporated by reference into any filing of the Company under the Securities Act of 1933 or the Securities Exchange Act of 1934, whether made before or after the date hereof and irrespective of any general incorporation language contained in such filing.

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