Datasheet

2
Functional Diagram
TRUTH TABLE
OUTPUT
ENABLE
SELECT
INPUT DATA INPUTS
257
OUTPUTS
258
OUTPUTS
OE S I
0
I
1
Y Y
HXXXZZ
LLLXLH
LLHXHL
LHXLLH
LHXHHL
H = High level voltage, L = Low level voltage, Z = High impedance (off) state, X = Don’t Care
2
5
11
14
6
13
10
3
4
7
12
9
4Y
3Y
2Y
1Y
1Y
4Y
3Y
2Y
AC/ACT
257
AC/ACT
258
1I
0
2I
0
3I
0
4I
0
1I
1
2I
1
3I
1
4I
1
S
OE
115
CD54/74AC257, CD54/74ACT257, CD74ACT258