Panasonic FA-A888 Service Manual ▷ View online
4-19
Electrical
Signal flow
Operation
Transport belt
motor
Original
reverse motor
2) Transport belt motor ( DTM )/ Original reverse motor( DRM ) drive circuit
This circuit controls the forward and reverse movement of the transport belt
motor and original reverse motor.
CPU output pin
Control motor
speed and
rotation direction
speed and
rotation direction
12~15
16~19
Gatearray output pin
C o n t r o l r o t a t i o n
torque
torque
17
16
• DTM drive circuit
IC13
13
14
15
14
15
12
PO0
PO1
PO2
PO3
PO3
IC14
17
PWM4
TP20
TP19
TP18
R45
68k
R91
12k
C14
0.1
C39
100p
100p
GND
PGND
13
15
14
16
16
9
11
8
10
5
4
A1
A2
A2
B1
B2
Vref
B2
Vref
Vref
Td1
Td2
Td1
Td2
PG
SG
+5V
C41
10
GND
2
3
6
7
7
IC5
A10
A20
B10
B20
B20
NC
CN3
4
3
3
2
1
1
PGND
5
6
+24V
C49
100
A
*A
*A
B
*B
Vp
Vp
Vp
• DRM drive circuit
IC13
17
18
19
18
19
16
PO4
PO5
PO6
PO7
PO7
IC14
16
PWM3
TP17
TP15
TP16
R46
68k
R94
6.2k
C13
0.1
C38
100p
100p
GND
PGND
13
15
14
16
16
9
11
8
10
5
4
A1
A2
A2
B1
B2
Vref
B2
Vref
Vref
Td1
Td2
Td1
Td2
PG
SG
+5V
C40
10
GND
2
3
6
7
7
IC2
A10
A20
B10
B20
B20
NC
CN6
8
7
7
6
5
5
PGND
3
4
+24V
C48
100
A
*A
*A
B
*B
Vp
Vp
Vp
SD012
SD013
Driver IC
Convert analog
signal for motor
signal for motor
IC5
IC2
4-20
3) Original feed solenoid ( DFSOL ),original reverse solenoid ( DRSOL ) drive
circuit
This circuit controls the original feed solenoid and the original reverse solenoid.
Operation of both the original feed solenoid and the original reverse solenoid
drive circuit is the same. When the drive signal from the gatearray becomes
HIGH, FET ( Q10,Q11 ) turns ON and the solenoid is activated.
(5) Original feed motor ( DFM ) current control circuit
This circuit controls the motor starting current within a limited current level.
IC14
15
14
PWM2
PWM1
R68
1k
R64
1k
Q11
Q10
1
2
3
PGND
2
1
3
PGND
D6
D7
+24V
+24V
CN7
4
5
Vp
DRSOL
Vp
CN4
DFSOL
4
3
+24V
OFF
ON
IC3 input
More than 0.32V
( 3.2A )
Less than 0.32V
( 3.2A )
Motor current
Controling
No controling
IC3 output
Low
High
IC14
63
M1CUR
TP4
+5V
IC3.2
1
2
3
TP2
R12
10k
C32
1000p
R63 R62
0.2
0.2
+24V
PGND
R44
R89
R72
22k
1k
3k
ZD6
PGND
IC15
4
5
5
PG1
PG2
SD014
SD015
4-21
Electrical
(6)Rush current control circuit
This circuit controls the rush current for the capacitors ( C48, C49 ) in the
transport belt motor and original belt motor drive circuits and is a limiting resistor
and FET.
This circuit limits the current by R93 until so the voltage of the cathode terminal
of ZD7 reaches the reference level ( 16V ). When all of the ADF open/close
detecting switch, original feed cover open/close switch, and original exit cover
switch are closed, or power is turned ON to the ADF. After the voltage of
cathode terminal of ZD7 reaches reference level, this control is cancelled. R30
is a discharge resistor for C48 and C49, when either ADF open/close detecting
switch, original feed cover open/close switch, or original exit cover switch is
opened.
(7) EEPROM ( IC7 ) circuit
This circuits memorizes the adjustment values of the ADF and original count
data. The data is not erased when the power switch turns OFF.
R93
15
3
2
1
+24V
C3
100p
R65
3k
R61
6.2k
Q12
2
3
PGND
1
Q4
PGND
ZD7
D5
R58 22k
R30
1.8k
C30
2.2
GND
To CN6-2
+5V
E2ROM+5V
D3
10
R81
R50
100k
IC7
6
7
C43
100
GND
ORG
TEST
D0 4
CS
CS
SK
DI
1
2
3
3
R54
R55
R56
R55
R56
R57
+5V
D2
R8
10k
IC13
GND
R19
R20
R21
(10k x 3)
(22k x 4)
59 AN13
51
P14
52 P15
50 P13
50 P13
SD016
SD017
4-22
(8) +5V power supply circuit
This circuit converts +24V which is supplied from the copier to +5V by a switching
regulator ( IC11 ). This circuit supplies +5V input voltage ( +24V ) is dropped
+9V.
(9) DC+24V Detecting circuit
This circuit is ZD4 and Q7 for monitoring +24V supplied from the copier. In
case power supplied from copier drops below +24V, this circuit detects and
inputs to the CPU ( IC13 ).
CN5
1
2 PGND
Vp
SW2
+24V
TP1
PGND
R84
9.1
C43
1500
D8
IC11
5
3
1
Vin
GND
Vo
C44
470
470
PGND
+5V
ZD5
GND
+24V
ZD4
C36
0.1
Q7
1
3
2
R29
10k
+5V
GND
GND
IC13
77
INTP5
SD018
SD019
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