INPUT AND OUTPUT EQUIVALENT CIRCUIT

TRUTH TABLE

INPUTS

OUTPUTS

CLK

ENABLE

SELECT

G1

G2

C

B

A

Y0

Y1

Y2

Y3

Y4

Y5

Y6

Y7

X

X

H

X

X

X

HHHH

HHHH

X

L

XXXX

HHHH

HHHH

H

L

L

L

L

L

HHH

HHHH

H

L

L

L

H

H

L

H

H

HHHH

H

L

L

H

L

H

H

L

H

HHHH

H

L

L

H

H

HHH

L

HHHH

H

L

H

L

L

HHHH

L

HHH

H

L

H

L

H

HHHH

H

L

HH

H

L

HH

L

HHHH

HH

L

H

H

L

HHH

HHHH

HHH

L

L

H

L

X

X

X

Outputs corresponding to stored address L: all others H

PIN DESCRIPTION

PIN No

SYMBOL

NAME AND FUNCTION

1, 2, 3

A, B, C

Data Inputs

4

CLK

Clock Input (LOW to

HIGH, Edge-triggered)

5

G2

Enable (Active LOW)

6

G1

Enable (Active HIGH)

9, 10, 11,

12, 13, 14,

15, 7

Y0, Y1, Y2,

Y3, Y4, Y5,

Y6, Y7

Data Outputs

8

GND

Ground (0V)

16

Positive Supply Voltage

IEC LOGIC SYMBOL

M54/M74HC131

2/12