Detector Circuit Of Sensor Signal; Start/Stop Control Circuit - Sharp SF-1020 Service Manual

(4) Detector circuit of sensor signal

The LS151 selects one signal of D0
tion of SEL A C signals (H, L) and outputs it to Y.
Selection of D0 D7 for SEL A
below.
SEL C SEL B SEL A
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
4
D0
3
D1
2
D2
1
D3
15
D4
14
D5
13
D6
12
D7
11
SEL A A
10
SEL B B
9
SEL C C
7
G
The sensor signal is in the following composition with the matrix of
SEL A C and S0 2.
S0 S1
SEL A PED1 —
A B
SEL B SW POD
SEL C PPD1 PNC
SEL A
+5V
1K
4.7K
I/O
10K
22K 2.2K
PE1
EE-SX1042
CSD0
SW601
MOTOR PWB 2 LS151
MOTOR PWB 3 LS151
D7 according to the combina-
C is made as shown in the table
Y
0
1
2
3
4
5
6
7
IC15
5
Y
74LS151
S2
CSD 0
CSD 1
CSD 2
+5V
HC04
24K
DTA123YS
+5V
HC04
24K
SEL B
+5V
CSD1
I/O
SW602
4.7K
4.7K
CPU POD
GP1S53
MAIN LS151
TMOTOR2 LS151
TMOTOR3 LS151
SEL C
+5V
1K
4.7K
I/O
PPD1
GP1S53
4.7K
CSD

(5) Start/stop control circuit

This circuit detects ON/OFF of the power and controls start/stop of
S0
the circuits.
The DC power section provides each power voltage (VH=+32V,
+24V, VC=+1-V, VD1=5V, VD2=5V).
When the power voltage reaches the specified level, the operation of
each circuit is started. Before the paper voltage falls below the
specified level, the operation of each circuit is stopped to prevent
against malfunctions.
S2
5V2
C5
C42
470µ F
22000PF
10V
12 – 11
+5V
24K
+5V
24K
+5V
10K
24K
22K 2.2K
DTA123YS
+5V
10K
24K
22K 2.2K
DTA123YS
+5V
PNC
24K
+5V
24K
5V2
R8
2.7KJ
IC13
1
VCC
/RESET
2 5
NC
GND
4 3
CAP
M51953BL
C4
1µ F
10V
S2
HC04
S0
HC04
S1
HC04
S0
HC04
S1
HC04
S2
HC04
RES ET 63
CPU
(IC 6)