Feed-Out Motor Circuit - Ricoh DF56 Service Manual

6.9 FEED-OUT MOTOR CIRCUIT

DF Main Board
CPU
High/Low
ON/OFF
The DF CPU sends the speed data (high or low) to the driver IC and the motor
drive circuit. The motor drive circuit creates the PWM signal and sends the mo-
tor drive pulses to the feed-out motor.
The frequency generator of the feed-out motor makes a very low voltage ac cur-
rent which is fed back to the driver IC. The driver IC monitors the frequency of
this ac current and based on the frequency it regulates the motor speed.
AC Feedback
Voltage
Regulation
Motor
Driver
Drive
IC
Circuit
7-19
30 November 1990
CN104-A2
FG
CN104-A15
CN104-B8
Feed-out
CN104-A12
Motor