IN74ACT21

1

High-Speed Silicon-Gate CMOS

The IN74ACT21 is identical in pinout to the LS/ALS21,

HC/HCT21. The IN74ACT21 may be used as a level converter

for interfacing TTL or NMOS outputs to High Speed CMOS

inputs.

• TTL/NMOS Compatible Input Levels

• Outputs Directly Interface to CMOS, NMOS, and TTL

• Operating Voltage Range: 4.5 to 5.5 V

• Low Input Current: 1.0 µA; 0.1 µA @ 25°C

• Outputs Source/Sink 24 mA

ORDERING INFORMATION

IN74ACT21N Plastic

IN74ACT21D SOIC

packages

PIN ASSIGNMENT

NC = NO CONNECTION

FUNCTION TABLE

Inputs

Output

A

B

C

D

Y

L

X

X

X

L

X

L

X

X

L

X

X

L

X

L

X

X

X

L

L

H

H

H

H

H

X = don’t care

LOGIC DIAGRAM

PIN 7 = GND

PINS 3,11 = NO CONNECTION