TECHNICAL DATA
IN74AC640
Octal 3-State Inverting
Bus Transceiver
High-Speed Silicon-Gate CMOS
The IN74AC640 is identical in pinout to the LS/ALS640,
HC/HCT640. The device inputs are compatible with standard CMOS
outputs; with pullup resistors, they are compatible with LS/ALS
outputs.
The IN74AC640 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.
•
Outputs Directly Interface to CMOS, NMOS, and TTL
•
Operating Voltage Range: 2.0 to 6.0 V
•
Low Input Current: 1.0
µA;
o.1
µA
@ 25°C
•
High Noise Immunity Characteristic of CMOS Devices
•
Outputs Source/Sink 24 mA
ORDERING INFORMATION
IN74AC640N Plastic
IN74AC640DW SOIC
T
A
= -40° to 85° C for all
packages
PIN ASSIGNMENT
LOGIC DIAGRAM
FUNCTION TABLE
Control Inputs
Output
Enable
L
Direction
L
Operation
Data Transmitted
from Bus B to
Bus A (inverted)
Data Transmitted
from Bus A to
Bus B (inverted)
Buses Isolated
(High Impedance
State)
L
PIN 20=V
CC
PIN 10 = GND
H
H
X
X = don’t care
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