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NEW PRODUCT NEWS—edited by Harv Weiner

KEYPAD INTERFACE IC

The EDE1144 Keypad Encoder IC provides a convenient, reliable means of connecting a multiplexed keypad to a microcontroller, and is ideal for embedded, OEM, and new product development use. It is designed to interface a matrix-type 4 row ý 4 column (16 key or less) keypad to a microcontroller or other host processor. A one-wire serial or four-wire parallel interface returns the keypress data and can be used in conjunction with a data valid signal for polled or interrupt-driven applications.

The EDE1144 provides enhanced keypad features such as contact debouncing and key auto-repeat. It lowers software overhead in the host microcontroller and reduces the I/O pin requirements from eight to one.

In addition, the EDE1144 is electrically quiet. Many keypad encoders continually scan the keypad, radiating EMI noise from the wires leading to the keypad (resulting in trouble during emissions testing and final product certification and approval). The EDE1144 reduces this problem by monitoring the keypad with unchanging signals, and then scanning only once each time a keypress is detected.

The EDE1144 is available in an 18-pin DIP or SOIC package and sells for $3.25 in quantities of 1000.

E-Lab Digital Engineering, Inc.
1600 N. 291 Hwy., Ste. 330
Independence, MO 64056
(816) 257-9954
Fax: (816) 257-9945
www.elabinc.com

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