FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL OMB Number: 3235-0104 Expires: January 31, 2005 Estimated average burden hours per response... 0.5

(Print or Type Responses)

1. Name and Address of Reporting Person *   YILMAZ HAMZA 2. Date of Event Requiring Statement (Month/Day/Year) 09/28/2012 3. Issuer Name and Ticker or Trading Symbol ALPHA & OMEGA SEMICONDUCTOR Ltd [AOSL] (Last) (First) (Middle) 475 OAKMEAD PARKWAY 4. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) Chief Technology Officer 5. If Amendment, Date Original Filed(Month/Day/Year) (Street) SUNNYVALE, CA 94085 6. Individual or Joint/Group Filing(Check Applicable Line) _X_ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Beneficially Owned

1.Title of Security (Instr. 4) 2. Amount of Securities Beneficially Owned (Instr. 4) 3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 4. Nature of Indirect Beneficial Ownership (Instr. 5) Common Shares 5,233 (1) D Â

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.			SEC 1473 (7-02)
	Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Employee Share Option (right to buy)	  (2)	02/06/2018	Common Shares	32,308	$ 13	D	Â
Employee Share Option (right to buy)	  (2)	02/06/2018	Common Shares	7,692	$ 13	D	Â
Employee Share Option (right to buy)	  (2)	05/04/2019	Common Shares	17,500	$ 7.6	D	Â
Employee Share Option (right to buy)	  (3)	05/04/2019	Common Shares	39,312	$ 7.6	D	Â
Employee Share Option (right to buy)	  (4)	05/04/2019	Common Shares	39,456	$ 7.6	D	Â
Employee Share Option (right to buy)	  (5)	05/04/2019	Common Shares	2,500	$ 7.6	D	Â
Employee Share Option (right to buy)	  (6)	08/12/2019	Common Shares	50,000	$ 8.4	D	Â
Employee Share Option (right to buy)	  (7)	11/11/2019	Common Shares	15,000	$ 10.5	D	Â
Employee Share Option (right to buy)	  (8)	04/27/2020	Common Shares	50,000	$ 18	D	Â
Employee Share Option (right to buy)	  (9)	03/06/2021	Common Shares	34,000	$ 12.68	D	Â
Employee Share Option (right to buy)	  (10)	04/25/2022	Common Shares	20,400	$ 9.9	D	Â

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
YILMAZ HAMZA 475 OAKMEAD PARKWAY SUNNYVALE, CA 94085	Â	Â	  Chief Technology Officer	Â

Signatures

/s/ Hamza Yilmaz		10/09/2012
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 5(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	Includes 4,061 shares subject to a restricted stock unit award granted on April 26, 2012 that will be issued as those units vest.
(2)	As of September 28, 2012, the option is fully vested and immediately exercisable for all option shares.
(3)	The option was granted on May 5, 2009 and becomes exercisable in a series of twenty-eight (28) successive equal monthly installments from 8/9/2010 to 12/9/2012.
(4)	The option was granted on May 5, 2009 and becomes exercisable in a series of thirty-six (36) successive equal monthly installments from 12/9/2009 to 12/9/2012.
(5)	The option was granted on May 5, 3009 and becomes exercisable with respect to all the underlying shares on January 9, 2013.
(6)	The option was granted on August 13, 2009 and becomes exercisable with respect to one-fifth (1/5) of the underlying shares on the first anniversary of the grant date, and thereafter the balance of the option shares become exercisable in a series of forty-eight (48) successive equal monthly installments.
(7)	The option was granted on November 12, 2009 and becomes exercisable with respect to one-fifth (1/5) of the underlying shares on the first anniversary of the grant date, and thereafter the balance of the option shares become exercisable in a series of forty-eight (48) successive equal monthly installments.
(8)	The option was granted on April 28, 2010 and becomes exercisable with respect to one-fifth (1/5) of the underlying shares on the first anniversary of the grant date, and thereafter the balance of the option shares become exercisable in a series of forty-eight (48) successive equal monthly installments.
(9)	The option was granted on March 7, 2011 and becomes exercisable with respect to one-fifth (1/5) of the underlying shares on the first anniversary of the grant date, and thereafter the balance of the option shares become exercisable in a series of forty-eight (48) successive equal monthly installments.
(10)	The option was granted on April 26, 2012 and becomes exercisable in a series of forty-eight (48) successive equal monthly installments.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, See Instruction 6 for procedure.

Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.