Sony OEP-4 Service Manual page 59

2. Stepping motor drive circuit
A stepping motor is driven using IC207 (current control-type drive circuit) on the MEC-24G board.
IC207 is compatible with micro step driving. IC207 can switch the excitation system of a stepping motor
by inputting the control signal at pins 98 and 55 of IC301 on the MA-142G board to pins 52 and 13 of
IC207. This unit employs 4W1-2 phase excitation (16-splitting). Moreover, the rotation direction of a
stepping motor is switched for driving by inputting the control signal at pin 47 of IC301 to pin 9 of
IC207. Pin 7 of IC207 functions as the reference voltage input for motor drive current control and as the
control input of motor drive output OFF. During motor stop, a motor drive current is turned off by
inputting a voltage (Vref) of Vref > 2.0 V from pin 45 of IC301.
In this unit, a grip roller and load roller are driven from a stepping motor through a belt. For except
during print and preheat, the motor power is designed to be not applied by controlling the control line (at
pin 3 of CN202) of power supply.
CN202
TO CN802/ 2pin
17 RESET_5V
MA-130
+5V
IC301
R807 R806
47
46
55
98
133
+
TO IC301
_
99 pin
R35 IC703
C732
GND
MA-142G
OEP-4
+5V
R205 R208 R206 R207 R209 R210 R204
C221
IC205
R220 R222 R224
R221 R223 R225
+5V STEMP
CN203
GND
VDD VBB
RESET OUTA1 A
CW/CCW OUTA2 /A
CLOCK OUTA1 COM
M2 OUTA2 COM
M1 OUTB1 /B
MO OUTB2 B
SYNC OUTB1
REF OUTB2
SENSEA
SENSEB
GND
IC207
R226 +
C204 C208 R229
R227
GND
GND
MEC-24G
1
2
3
4
5
6
5-11