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NEW PRODUCT NEWS—edited by Harv Weiner

Serial Keyboard Encoder

The USAR SerialCoder IC consumes minimum power, making it ideal for add-on keyboards for hand-held devices, cellular phones, and single-board systems designed for portable applications. A patent-pending technique, Self Power Management, enables the keyboard to sleep during periods of inactivity. Because inactivity includes the time between keystrokes, the keyboard is almost always sleeping. Typical power consumption is less than 2 nA (at 5 V, 25ęC). When the keyboard is activated, data is sent immediately, so nothing is lost. The encoder also detects heavy objects inadvertently pressing keys and powers-down.

Because the USAR SerialCoder detects the location of a pressed key rather than detecting a defined key, the IC works with most keyboards. The keyboard encoder scans and debounces an 8ð² x 16ð² matrix. The IC also provides an innovative algorithm to detect and eliminate "ghost" keys. It requires few external components and uses a small, low-profile 32-pin LQFP package that measures 7 mm x 7 mm.

The USAR SerialCoder costs less than $3.50 in OEM quantities.

USAR Systems, Inc.
(212) 226-2042
Fax: (212) 226-3215
www.usar.com

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