Philips MX-1050D, Руководство по обслуживанию

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6-4
M74HC138 INTERNAL BLOCK & TRUTH TABLE
15
&
G
0
7
0
2
DX
0
1
7
6
5
4
3
2
7
9
10
11
12
13
14
1
2
3
4
5
6
16
8
A
B
C
G2A
G2B
G1
Vcc
GND
Y0
Y1
Y2
Y3
Y4
Y5
Y6
Y7
G2B
X
X
H
L
L
L
L
L
L
L
L
G2B
X
H
X
L
L
L
L
L
L
L
L
G1
L
X
X
H
H
H
H
H
H
H
H
C
X
X
X
L
L
L
L
H
H
H
H
B
X
X
X
L
L
H
H
L
L
H
H
A
X
X
X
L
H
L
H
L
H
L
H
Y0
H
H
H
L
H
H
H
H
H
H
H
Y2
H
H
H
H
H
L
H
H
H
H
H
Y3
H
H
H
H
H
H
L
H
H
H
H
Y4
H
H
H
H
H
H
H
L
H
H
H
Y5
H
H
H
H
H
H
H
H
L
H
H
Y6
H
H
H
H
H
H
H
H
H
L
H
Y7
H
H
H
H
H
H
H
H
H
H
L
Y1
H
H
H
H
L
H
H
H
H
H
H
ENABLE SELECT
INPUTS
OUTPUTS
TRUTH TABLE
X = Don't care
Command decoder
Display memory
24 buts x 12 words
Serial
Interface
OSC
Timing generator
key scan
Key data memory(2x16 bits)
Dimming circuit
24-bit output latch
Segment dr
iv
er
m
ultiple
x
ed dr
iv
er
Data selector
12-bit shift register
Gr
id dr
iv
er
Grid
4
Grid
1
Seg
17
/Grid
12
Seg
24
/Grid
5
Seg
1
/KS
1
Seg
16
/KS
16
D
IN
D
OUT
CLK
STB
OSC
Key1, Key2
LED
4
LED
1
4-bit latch
V
DD
(+5V)
V
SS
(0V)
V
EE
(-30V)
1
4
5
6
7
8
9
10, 11
12,
44 13,
43
30
14
29
31
38
39
42
uPD16315
UPD16315 INTERNAL BLOCK