JVC TH-A75 Service Manual page 20

TH-A75
4.4 MM74HCT32MTC-X (IC521) : Quad 2 input OR gate
• Pin layout & Block diagram
1A
1B
1Y
2A
2B
2Y
GND
4.5 74LCX373MTC-X (IC512,IC513) : Octal D-type latch
• Pin layout
OE 1
Q0 2
D0 3
D1 4
Q1 5
Q2 6
D2 7
D3 8
Q3 9
GND 10
• Block diagram
D0 D1
3 4
D D
Q Q
L L
11
LE
1
OE
2 5
Q0 Q1
1-20 (No.22009)
1 14 V
CC
2 13 4B
3 12 4A
4 11 4Y
5 10 3B
6 9 3A
7 8 3Y
(TOP VIEW)
20 VCC
19 Q7
18 D7
17 D6
16 Q6
15 Q5
14 D5
13 D4
12 Q4
11 LE
(TOP VIEW)
D2 D3 D4 D5
7 8 13 14
D D D D
Q Q Q
L L L
6 9 12
Q2 Q3 Q4
• Truth table
INPUTS
A
L
L
H
H
• Truth table
OE
H
L
L
L
X: Don't care
Z: High impedance
Qn: Q outputs are latched at the time when the LE input is tak-
en to a low logic level.
D6 D7
17 18
D D
Q Q Q
L L L
15 16 19
Q5 Q6 Q7
OUTPUT
B Y
L L
H H
L H
H H
INPUTS OUTPUT
LE D Y
X X Z
L X Qn
H L L
H H H