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ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104

Part Number KBDP64

KBDP64 IC

Parallel output keyboard encoder for up to 64 keys

General Description

The KBDP64 IC is designed to provide a parallel binary output encoder for keyboards up to 64

keys. The KBDP64 IC contains all the logic necessary to encode a SPST keyboard switch array

up to 8 by 8 in size and provide a parallel binary output and a data available strobe. The data

available strobe goes high when a key is pressed, and goes low when the key is released. The

data outputs keep their states after the key is released. The array can be a 8 x 8 array, but any

smaller size may be used. The KBDP64 handles debouncing and encodes the keys with no

external parts. All timing is internally generated. No external diodes are required in the array to

prevent key ghosting in a two key rollover situation.

A .1 uF bypass capacitor is suggested

across the VDD and VSS pins. The part uses the standard 28 pin .3 inch width SOIC package.

Features