74ACT257_01 Datasheet, PDF (2/11 Pages) STMicroelectronics – QUAD 2 CHANNEL MULTIPLEXER (3-STATE)

74ACT257
INPUT AND OUTPUT EQUIVALENT CIRCUIT
PIN DESCRIPTION
PIN No
1
2, 5, 11, 14
3, 6, 10, 13
4, 7, 9, 12
15
8
16
SYMBOL
SELECT
1A to 4A
1B to 4B
1Y to 4Y
OE
GND
V_CC
NAME AND FUNCTION
Common Data Select
Inputs
Data Inputs From Source
A
Data Inputs From Source
B
Multiplexer Outputs
3 State Output Enable
Inputs (Active LOW)
Ground (0V)
Positive Supply Voltage
TRUTH TABLE
OE
H
L
L
L
L
X : Don’t Care
Z : High Impedance
LOGIC DIAGRAM
INPUTS
SELECT
A
X
X
L
L
L
H
H
X
H
X
OUTPUT
B
Y
X
Z
X
L
X
H
L
L
H
H
This logic diagram has not be used to estimate propagation delays
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