TECHNICAL DATA

IN74ACT640

Octal 3-State Inverting

Bus Transceiver

High-Speed Silicon-Gate CMOS

ORDERING INFORMATION

IN74ACT640N Plastic

IN74ACT640DW SOIC

The IN74ACT640 is identical in pinout to the LS/ALS640,

HC/HCT640. The IN74ACT640 may be used as a level converter for

interfacing TTL or NMOS outputs to High Speed CMOS inputs.

The IN74ACT640 is a 3-state transceiver that is used for 2-way

asynchronous communication between data buses. The device has an

active-low Output Enable pin, which is used to place the I/O ports into

high-impedance states. The Direction control determines whether data

flows from A to B or from B to A.

• 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

PIN ASSIGNMENT

LOGIC DIAGRAM

PIN 10 = GND

FUNCTION TABLE

Control Inputs

Output

Enable

Direction

Operation

L

L

Data Transmitted

from Bus B to

Bus A (inverted)

L

H

Data Transmitted

from Bus A to

Bus B (inverted)

H

X

Buses Isolated

(High Impedance

State)

X = don’t care

Rev. 00