IN74ACT640
OCTAL 3-STATE INVERTING
BUS TRANSCEIVER
High-Speed Silicon-Gate CMOS
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
ORDERING INFORMATION
• 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
IN74ACT640N Plastic
IN74ACT640DW SOIC
TA = -40° to 85° C for all
packages
PIN ASSIGNMENT
LOGIC DIAGRAM
FUNCTION TABLE
Control Inputs
Output Direction
Enable
Operation
L
L
H
X
Data
Transmitted
from Bus B to
Bus A (inverted)
Data
PIN 20=VCC
PIN 10 = GND
L
Transmitted
from Bus A to
Bus B (inverted)
Buses Isolated
(High
H
Impedance
State)
X = don’t care
1
INTEGRAL [ INTEGRAL CORP. ]
