Philips pm2521 - Page 114

Hef4051B
8-CHANNEL ANALOGUE
MULTIPLEXER/DEMULTIPLEXER
Functional diagram
[iil [Til [Tsl
[121 rnl
ra m
''dD
'^2
Yl
Yq Y3
0
< A2
D
HEF
4051
B
Y4 Vg Z Y7
Y5 E
Vee YSS
llJ I
2J UJ [AJ LlJ LLl 12J L§J
Pinning diagram
PINNING
Yq
1^0 independent inputs/outputs
Aq
to
A2
address inputs
E
enable input (active LOW)
Z
common
input/output
FUNCTION
TABLE
inputs
channel
ON
E
Az
1
0
<
L
L L
L
L L L H
L
L H L
y
’-2
L
L H H
L
H L L
L H
L H
L
H H
L
L
H H H
H
X X X none
H
=
HIGH
state (the
more positive voltage)
L
=
LOW
state (the less
positive voltage)
X
=
state in immaterial