December 1990

4

Philips Semiconductors

Product specification

8-bit synchronous BCD down counter

74HC/HCT40102

FUNCTION TABLE

Notes

1. Clock connected to CP.

2. Synchronous operation: changes occur on the LOW-to-HIGH CP transition.

H = HIGH voltage level

L = LOW voltage level

X = don’t care

CONTROL INPUTS

PRESET MODE

ACTION

MR

PL

PE

TE

HH

H

H

synchronous

inhibit counter

H

H

H

L

count down

H

H

L

X

preset on next LOW-to HIGH clock transition

HL

X

X

asynchronous

preset asynchronously

L

X

X

X

clear to maximum count

Fig.4 Functional diagram.