KBDSER132 Datasheet, PDF (1/9 Pages) ABCircuits – Serial output keyboard encoder for up to 132 keys

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KBDSER132 IC
Serial output keyboard encoder for up to 132 keys
General Description
The KBDSER132 IC is designed to provide a serial binary output encoder for keyboards up to
132 keys. The KBDSER132 IC contains all the logic necessary to encode a SPST keyboard
switch array up to 12 by 11 in size and provide a serial binary output. The output is standard
asynchronous format, using 8 bits, 1 stop and no parity at 9600 BPS. Other formats and
encoding are available, contact the factory. The array can be a 12 x 11 array, but any smaller
size may be used. The KBDSER132 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
• Asynchronous serial output.
• Fully encodes a key switch array. (up to 12 x11)
• No external parts required.
• Low power consumption 2 mA typical.
• Supply voltage 2.4 to 5.25 volts.
• All timing internally generated.
• 2 Key rollover.
• On chip row input resistors.
• Internal key bounce elimination.
• TTL and CMOS compatible outputs.
• Part is in full production.
• SOIC 28 Pin Package.
• Low EMI
• ROHS Compliant
Part Number KBDSER132
January 2013 Page 1 of 9