M74HC243

2/11

INPUT AND OUTPUT EQUIVALENT CIRCUIT

PIN DESCRIPTION

TRUTH TABLE

LOGIC DIAGRAM

This logic diagram has not be used to estimate propagation delays

PIN No

SYMBOL

NAME AND FUNCTION

1GAB

Output Enable Input

(Active LOW)

2, 12

NC

Not Connected

3, 4, 5, 6

1A to 4A

Data Inputs/Outputs

11, 10, 9, 8

1B to 4B

Data Inputs/Outputs

13

GBA

Output Enable Input

7

GND

Ground (0V)

14

Positive Supply Voltage

INPUTS

FUNCTION

OUTPUTS

GAB

GBA

A BUS

B BUS

H

H

OUTPUT

INPUT

A = B

L

L

INPUT

OUTPUT

B = A

H

L

HIGH IMPEDANCE

Z

L

H

HIGH IMPEDANCE

Z