Important Additional Information

This communication is for informational purposes only and does not constitute an offer to buy any securities or a solicitation of any vote or approval or a solicitation of an offer to sell any securities. MICROCHIP AND ON SEMICONDUCTOR INTEND TO FILE A PROXY STATEMENT WITH THE SECURITIES AND EXCHANGE COMMISSION (THE “SEC”) RELATING TO MICROCHIP’S AND ON SEMICONDUCTOR’S SOLICITATION OF PROXIES FROM THE SHAREHOLDERS OF ATMEL FOR USE AT THE 2009 ANNUAL MEETING OF SHAREHOLDERS. ALL ATMEL SHAREHOLDERS ARE URGED TO READ THE PROXY STATEMENT FILED WITH THE SEC CAREFULLY IN ITS ENTIRETY WHEN IT BECOMES AVAILABLE BECAUSE IT WILL CONTAIN IMPORTANT INFORMATION.

SHAREHOLDERS WILL BE ABLE TO OBTAIN FREE COPIES OF THE PROXY STATEMENT FILED WITH THE SEC BY MICROCHIP AT WWW.MICROCHIP.COM, BY ON SEMICONDUCTOR AT WWW.ONSEMI.COM, AND THROUGH THE WEB SITE MAINTAINED BY THE SEC AT WWW.SEC.GOV. FREE COPIES OF THE PROXY STATEMENT CAN ALSO BE OBTAINED BY DIRECTING A REQUEST TO MICROCHIP’S AND ON SEMICONDUCTOR’S PROXY SOLICITOR, MACKENZIE PARTNERS, INC. AT (650) 798-5206.

Each of Microchip and ON Semiconductor and their respective directors and executive officers and other persons may be deemed to be participants in the solicitation of proxies from shareholders of Atmel in connection with the election of directors and other matters. As of the date hereof, Microchip beneficially owns approximately 4.1% of Atmel’s outstanding common stock. Information regarding Microchip’s and ON Semiconductor’s directors and executive officers is available in Microchip’s SEC filings (including Microchip’s Annual Report on Form 10-K for the fiscal year ended March 31, 2008 and its Proxy Statement for its 2008 Annual Meeting of Shareholders) and ON Semiconductor’s SEC filings (including ON Semiconductor’s Annual Report on Form 10-K for the fiscal year ended December 31, 2007 and its Proxy Statement for its 2008 Annual Meeting of Shareholders), respectively. Other information regarding the participants in the proxy solicitation and a description of their direct and indirect interests will be contained in the Proxy Statement to be filed by Microchip and ON Semiconductor with the SEC when it becomes available.

About Microchip Technology

Microchip Technology Incorporated (NASDAQ: MCHP) is a leading provider of microcontroller and analog semiconductors, providing low-risk product development, lower total system cost and faster time to market for thousands of diverse customer applications worldwide. Headquartered in Chandler, Ariz., Microchip offers outstanding technical support along with dependable delivery and quality. For more information, visit the Microchip’s website at www.microchip.com.

About ON Semiconductor

With its global logistics network and strong product portfolio, ON Semiconductor Corporation (NASDAQ: ONNN) is a preferred supplier of high performance, energy efficient, silicon solutions to customers in the power supply, automotive, communication, computer, consumer, medical, industrial, mobile phone, and military/aerospace markets. The company’s broad portfolio includes power, analog, DSP, mixed-signal, advance logic, clock management, non-volatile memory and standard component devices. Global corporate headquarters are located in Phoenix, Arizona. The company operates a network of manufacturing facilities, sales offices and design centers in key markets throughout North America, Europe, and the Asia Pacific regions. For more information, visit http://www.onsemi.com.

Microchip Investor Contacts:
MacKenzie Partners
Amy Bilbija, 650-798-5206
Email Contact
or
Microchip Media Contacts:
Sard Verbinnen & Co
David Reno, 212-687-8080
Email Contact
Andrew Cole or Ron Low, 415-618-8750
Email Contact / Email Contact
or
ON Semiconductor Investor Contacts:
Ken Rizvi, 602-244-3437
Email Contact
or
ON Semiconductor Media Contacts:
Anne Spitza, 602-244-6398
Email Contact