CD54HCT640 Datasheet, PDF (2/11 Pages) Texas Instruments – High-Speed CMOS Logic Octal Three-State Bus Transceiver, Inverting

CD54HC640, CD74HC640, CD54HCT640, CD74HCT640
Functional Diagram
A0
B0
A1
THRU
A6
B1
THRU
B6
A7
B7
OE
OUTPUT ENABLE AND
DIR
DIRECTION-SELECT LOGIC
V_CC = 20
GND = 10
TRUTH TABLE
CONTROL INPUTS
DATA PORT STATUS
OE
DIR
A_n
B_n
L
L
O
I
H
H
Z
Z
H
L
Z
Z
L
H
I
O
To prevent excess currents in the High-Z modes all I/O terminals
should be terminated with 1kΩ to 1MΩ resistors.
H = High Level
L = Low Level
I = Input
O = Output (Inversion of Input Level)
Z = High Impedance
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