74HC257 Datasheet, PDF (4/13 Pages) NXP Semiconductors – Quad 2-input multiplexer 3-state

Philips Semiconductors
Quad 2-input multiplexer; 3-state
Product specification
74HC/HCT257
1S
23
1I0 1I1
56
2I0 2I1
11 10
3I0 3I1
14 13
4I0 4I1
SELECTOR
15 OE
3-STATE MULTIPLEXER OUTPUTS
1Y
2Y
3Y
4Y
4
7
12
9
MGR280
Fig.4 Functional diagram.
FUNCTION TABLE
INPUTS
OE
S
nI₀
nI₁
H
X
X
X
L
H
X
L
L
H
X
H
L
L
L
X
L
L
H
X
Notes
1. H = HIGH voltage level
L = LOW voltage level
X = don’t care
Z = high impedance OFF-state
OUTPUT
nY
Z
L
H
L
H
Fig.5 Logic diagram.
1998 Sep 30
4