Alpha and Omega Semiconductor 475 Oakmead Parkway, Sunnyvale, California 94085 USA FOR IMMEDIATE RELEASE Media Contact: Martha Aparicio Tel: 408.789.3233 Email: [email protected] Alpha and Omega Semiconductor Expands its 600V AlphaMOS™ Portfolio with Rugged Solutions for the Lighting Market Robust MOSFETs deliver high performance and reliability for LED and CFL lighting SUNNYVALE, Calif., April 26, 2013 – Alpha and Omega Semiconductor Limited (AOS) (Nasdaq: AOSL), a designer, developer and global supplier of a broad range of power semiconductors and power ICs, today announced the release of AOD4C60, AOD3C60, and AOD2HC60, the newest additions to its 600V AlphaMOS portfolio, which combines features such as robustness, controlled switching and low on-resistance to produce high-performing devices. These new products are well suited for commercial and industrial CFL ballasting as well as LED lighting for residential and commercial applications. These new devices are built using proprietary AlphaMOS technology, designed for efficient switching and dependable reliability. The device structure of these solutions allows for a smooth dv/dt and di/dt transition during hard switching, thereby reducing the ringing typically experienced with other superjunction-type devices. Furthermore, these devices offer 3x the avalanche current capability versus comparable superjunction solutions and enables power circuits to outlast fault conditions such as power line surges and lighting surges. These solutions are available in 4A, 3A, and 2.5A varieties in the DPAK green package and are 100% Rg and UIS tested. “As builders and homeowners move towards replacing conventional lighting fixtures with LED lighting, there is an ever increasing need for power solutions that are robust and efficient.” said Stephen Chang, Sr. Product Marketing Manager at AOS. “Our newest 600VAlphaMOS additions offer excellent avalanche ratings in addition to smooth switching performance to meet these power requirements.” AOD4C60 Technical Highlights 600V N-channel MOSFET ID = 4A RDS(ON) < 0.95 Ohms max at VGS = 10V COSS = 41 pF typ Qg (10V) = 14 nC typ AOD3C60 Technical Highlights 600V N-channel MOSFET ID = 3A RDS(ON) < 1.4 Ohms max at VGS = 10V COSS = 29 pF typ Qg (10V) = 10.3 nC typ Tel: 408.830.9742 • Fax: 408.830.9757 • www.aosmd.com 1 AOD2HC60 Technical Highlights 600V N-channel MOSFET ID = 2.5A RDS(ON) < 2 mOhms max at VGS = 10V COSS = 23 pF typ Qg (10V) = 7.6 nC typ Pricing and Availability The AOD4C60, AOD3C60, and AOD2HC60 are immediately available in production quantities with a lead-time of 12-14 weeks. The unit prices for 10,000 pieces of each device are $0.53, $0.43, and $0.31 respectively. About AOS Alpha and Omega Semiconductor Limited, or AOS, is a designer, developer and global supplier of a broad range of power semiconductors, including a wide portfolio of Power MOSFET, IGBT and Power IC products. AOS has developed extensive intellectual property and technical knowledge that encompasses the latest advancements in the power semiconductor industry, which enables us to introduce innovative products to address the increasingly complex power requirements of advanced electronics. AOS differentiates itself by integrating its Discrete and IC semiconductor process technology, product design, and advanced packaging know-how to develop high performance power management solutions. AOS's portfolio of products targets high-volume applications, including portable computers, flat panel TVs, LED lighting, smart phones, battery packs, consumer and industrial motor controls and power supplies for TVs, computers, servers and telecommunications equipment. For more information, please visit www.aosmd.com. Forward Looking Statements This press release contains forward-looking statements that are based on current expectations, estimates, forecasts and projections of future performance based on management's judgment, beliefs, current trends and anticipated product performance. These forward-looking statements include, without limitation, references to the efficiency and capability of new products, and the potential to expand into new markets. Forward looking statements involve risks and uncertainties that may cause actual results to differ materially from those contained in the forward-looking statements. These factors include, but are not limited to, the actual product performance in volume production, the quality and reliability of the product, our ability to achieve design wins, the general business and economic conditions, the state of the semiconductor industry, and other risks as described in the Company's annual report and other filings with the U.S. Securities and Exchange Commission. Although the Company believes that the expectations reflected in the forward looking statements are reasonable, it cannot guarantee future results, level of activity, performance, or achievements. You should not place undue reliance on these forward-looking statements. All information provided in this press release is as of today's date, unless otherwise stated, and AOS undertakes no duty to update such information, except as required under applicable law. ### Tel: 408.830.9742 • Fax: 408.830.9757 • www.aosmd.com 2