Brother FAX-170 Service Manual page 32

1 2
A
B
C
A B U S
1 7 D
D
E
D A B U S
1 4 D
D B U S
1 4 E
F
1 2
2
1 E PROM (16k x 1 bit)
2 ROM (256k x 8 bits. Note that the qualification machines for demonstration have a 2-
megabit ROM.)
3 DRAM (512k x 8 bits)
4 Backup circuit for the calendar clock of the control panel and DRAM.
3 4
2
D A 9
# 1 3
P D 2 7 C 2 0 0 1 A
D A 8 3 0 R M R D + 5
2 4
A 1 7 - 0 E
1 6 B
D A 7 2 R O M C
2 2
A 1 6
1 6 B
- C E
R 1 0 9
D A 6 3
A 1 5 0
( D S : N C )
D A 5 2 9
3 1
A 1 4
- P G M
D A 4 2 8
A 1 3
R 1 0 9
D A 3 4 3 2 + 5
A 1 2 N C
V C C
( D S : 0
A 1 1 2 5 1
A 1 1 C 7 7
V P P
1 0 4
A 1 0 2 3
A 1 0
A 9 2 6
1 6
A 0 9
G N D
A 8 2 7
A 0 8
D 7
A 7 5
2 1
A 0 7
D 7
A 6 6 D 6
2 0
A 0 6
D 6
A 5 7 D 5
1 9
A 0 5
D 5
A 4 8 D 4
1 8
A 0 4
D 4
A 3 9 D 3
1 7
A 0 3
D 3
A 2 1 0 D 2
1 5
A 0 2
D 2
A 1 1 1 D 1
1 4
A 0 1
D 1
A 0 1 2 D 0
1 3
A 0 0
D 0
+ 5 B
3
1 0 4
B A R M W E
1
1 6 A
V C C W
B A R M R D
1 4
V C C 0 E 1 6 B
1 5 C A S
1 6 A
G N D C A S
2 8 R A S 0
1 6 A
G N D R A S
G N D
D A 9
9 6
A 9 N C
D A 8 2 0 2 1
A 8 N C
D A 7
1 9
A 7
D A 6 D 7
1 8 2 7
A 6
I / 0 7
D A 5 D 6
1 7 2 6
A 5 I / 0 6
D A 4 D 5
1 6 2 5
A 4 I / 0 5
D A 3 2 4 D 4
1 3
A 3 I / 0 4
D A 2 1 2 5 D 3
A 2 I / 0 3
D A 1
1 1 4 D 2
A 1 I / 0 2
D A 0 3 D 1
1 0
A 0 I / 0 1
D 0
2
I / 0 0
# 1 4
H M 5 1 4 8 0 0 J P
3 4
Main PCB Circuit Diagram 2/5
5
)
4
+ 9 V
D A 1
1 S S 3 7 8
1 2
3
L 1 8
B A T R 1 0 4
0
1
P 1 6 1 K
L 1 9
0
C 9 2
2
2
1 0 4
P 1 6
V C C 3
Q 7
O U T
P 1 6
R H 5 R A 4 7
B 2 B - P H
G N D
1
G N D
5
III – 25
6 7
1
C 2 9
1 0 4
+ 5
1 8
V C C
A 0
7
2
N C
A 1
6
3
A 2 S C L 1 7 E E P C K
4 5
S D A 1 6 E E P D 0
V S S
R 4 2
+ 5
4 . 7 K
* # 7
2 4 L C 3 2
R V D D
D 5 R 7 6
+ 5
N C + 5 B
N C
C 6 4
N C
L 1 7
0
G N D
6 7
8
A
B
C
D
C 7 2
1 0 V 1 0 0
E
F
8