Sharp AR-168S Service Manual page 134

(7) Toner motor control circuit
The IC32 is the motor drive IC, which generates pseudo-AC wave-
forms by the pulse signal from the ASIC to drive the toner supply
motor.
(4-D3) (TM)
(4-D3) (TM_)
(8) Main motor control circuit/ LSU (Polygon motor)
control circuit
The motors are driven by the MMD (main motor) signal and the PMD
(polygon motor) signal from the ASIC.
The MMD signal and the PMD signal are turned HIGH and sent
IC27
1
(2-C1) MMD
1B 1C
2
(2-A3) MM_Y1
2B 2C
3
(2-A3) MM_Y2
3B 3C
4
(2-C1) MM_Y3
4B 4C
5
(1-D3) POFF
5B 5C
6
(2-C1) PMD
6B 6C
7
(2-C1)
/LEND 7B 7C
8
G NC
KID65503F
(9) Mirror motor control circuit, SPF motor control circuit,
Duplex motor control circuit, Shifter motor control
circuit.
Stepping motors are employed for the mirror motor, the SPF motor,
and the duplex motor. The driver for IC29 (for the mirror motor) is the
bipolar drive constant current drive IC. The drive for IC31 (for the SPF)
is the uni-polar drive constant current drive IC. The drive for IC28 (for
the duplex) and IC30 (for the shifter) is the constant current drive IC.
Each motor is driven in W1-2 phase excitement, 1-2 phase excitement,
or 2-phase excitement.
The mirror motor/SPF motor related to image scan are driven by a con-
stant current, and each motor current is switched in each magnification
ratio.
Tonner Motor Driver
R105
1kJ
1 2
1 2
R106
1kJ
R112 R113
47kJ 47kJ
PGND
5V
16
R88
/MMD (11-A4)
15
10kJ Q3
MMref0 (6-A3)
14
KRC106S
MMref1 (6-A3)
13
MMref2 (6-A3)
12
/POFF (10-B4)
11
/PMD (11-B2)
2
10
9
AR-168S/168D ELECTRICAL SECTION 13 - 9
C128
10u/35V
IC32
PGND
17
Vcc
19 16
PSAVE VM
20 9
Rin OUT1
18 5
Fin OUT2
21
VREF
6
RNF
1 8
NC GND
2 FIN
NC FIN
3
NC
4 25
NC NC
7 24
NC NC
10 23
NC NC
11 22
NC NC
12 15
NC NC
13 14
NC NC
BA6920FP
PGND
through the driver IC27 to the control circuit in the main motor/LSU,
rotating each motor.
When the motor RPM reaches the specified level, the MMLD signal
(main) and the PMLD signal (LSU) become LOW. The CPU detects it
to start process control.
3
SHOLD (11-B2)
24V
+
C129
0.1u/50V
TMB_O (11-A1)
TMA_O (11-A1)