M54HC166

2/11

IEC LOGIC SYMBOLS

INPUT AND OUTPUT EQUIVALENT CIRCUIT

PIN DESCRIPTION

TRUTH TABLE

X : Don’t Care

a........h : The level of steady input voltage at inputs a through H respectively

PIN N°

SYMBOL

NAME AND FUNCTION

1

SI

Serial Data Inputs

2, 3, 4, 5, 10,

11, 12, 14

A to H

Parallel Data Inputs

6CLOCK INH

Clock Enable Input

(Active Low)

7CLOCK

Clock Input (LOW to

HIGH, Edge Triggered

9

CLEAR

Asynchronous Master

Reset Input (Active Low)

13

Serial Output from the

Last Stage

15

SHIFT/LOAD

Parallel Enable Input

(Active Low)

8

GND

Ground (0V)

16

Positive Supply Voltage

INPUTS

INTERNAL OUTPUTS

OUTPUTS

CLEAR

SHIFT/

LOAD

CLOCK

INH

CLOCK

SERIAL IN

PARALLEL

A..........H

QA

QB

QH

L

XXX

XX

L

L

L

L

X

X

X

X

NO CHANGE

H

L

L

X

a..............h

a

b

h

H

H

L

H

X

H

QAn

QGn

H

H

L

L

X

L

QAn

QGn

H

X

H

X

X

X

NO CHANGE