Logic Diagram; Function Table - Philips 74F257A Datasheet

Philips Semiconductors
Quad 2-line to 1-line selector/multiplexer, non-inverting
(3-State)

LOGIC DIAGRAM

OE I0a I1a I0b I1b
15 2 3 5 6
4 7
Ya Yb
V = Pin 16
CC
GND = Pin 8
APPLICATION
S2
S1
S0
WORD A WORD B
I0a I1a I0b I1b I0c I1c I0d I1d
OE
74F257A
S
Ya Yb Yc
4-BIT
DATA
BUS
1995 Mar 31
I0c I1c I0d I1d S
11 10 14 13 1
9 12
Yc Yd
SF00676
ENABLE C
B
A
WORD C WORD D
I0a I1a I0b I1b I0c I1c I0d I1d
OE
74F257A
S
Yd Ya Yb Yc

FUNCTION TABLE

INPUTS
OE S
H X
L H
L H
L L
L L
H = High voltage level
L = Low voltage level
X = Don't care
Z = High impedance "off" state
74F139
Y0 Y1 Y2 Y3
WORD E WORD F
I0a I1a I0b I1b I0c I1c I0d I1d
OE
74F257A
S
Yd Ya Yb Yc Yd
3
Product specification
74F257A
OUTPUT
I0 I1 Y
X X Z
X L L
X H H
L X L
H X H
WORD G WORD H
I0a I1a I0b I1b I0c I1c I0d I1d
OE
74F257A
S
Ya Yb Yc Yd
SF00677