Datasheet

December 1990 5
Philips Semiconductors Product specification
8-bit addressable latch 74HC/HCT259
FUNCTION TABLE
Notes
1. H = HIGH voltage level
L = LOW voltage level
X = don’t care
d = HIGH or LOW data one set-up time prior to the LOW-to-HIGH LE transition
q = lower case letters indicate the state of the referenced output established during the last cycle in which it was
addressed or cleared
OPERATING
MODES
INPUTS OUTPUTS
MR LE D A
0
A
1
A
2
Q
0
Q
1
Q
2
Q
3
Q
4
Q
5
Q
6
Q
7
master reset L H X X X X L L L L L L L L
demultiplex
(active HIGH)
decoder
(when D = H)
L
L
L
L
L
L
L
L
d
d
d
d
L
H
L
H
L
L
H
H
L
L
L
L
Q=d
L
L
L
L
Q=d
L
L
L
L
Q=d
L
L
L
L
Q=d
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
d
d
d
d
L
H
L
H
L
L
H
H
H
H
H
H
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
Q=d
L
L
L
L
Q=d
L
L
L
L
Q=d
L
L
L
L
Q=d
store (do nothing) H H X X X X q
0
q
1
q
2
q
3
q
4
q
5
q
6
q
7
addressable latch
H
H
H
H
L
L
L
L
d
d
d
d
L
H
L
H
L
L
H
H
L
L
L
L
Q=d
q
0
q
0
q
0
q
1
Q=d
q
1
q
1
q
2
q
2
Q=d
q
2
q
3
q
3
q
3
Q=d
q
4
q
4
q
4
q
4
q
5
q
5
q
5
q
5
q
6
q
6
q
6
q
6
q
7
q
7
q
7
q
7
H
H
H
H
L
L
L
L
d
d
d
d
L
H
L
H
L
L
H
H
H
H
H
H
q
0
q
0
q
0
q
0
q
1
q
1
q
1
q
1
q
2
q
2
q
2
q
2
q
3
q
3
q
3
q
3
Q=d
q
4
q
4
q
4
q
5
Q=d
q
5
q
5
q
6
q
6
Q=d
q
6
q
7
q
7
q
7
Q=d