Controlling The Pick-Up Motor - Canon FY8-13FW-000DADF-A1 Service Manual

I. Controlling the Pick-Up Motor
1. Outline
Figure 2-267 is a block diagram of the pick-up motor.
The feeder motor is a DC motor. The microprocessor (Q1) on the DADF controller PCB sends
to the drive circuit the pick-up motor drive signal (SMON), pick-up motor rotation direction signal
(SDIR), and pick-up motor rotation speed control signal (SMPWM).
In response, the drive circuit drives the pick-up motor according to these three signals.
The control circuit is not equipped with a circuit used to provide the microprocessor (Q1) with
feed back, indicating the state of pick-up rotation. As such, the pick-up motor rotation speed control
signal (SMPWM) remains constant at all times, and no correction is made when the rotation speed of
the pick-up motor fluctuates because of an external force.
Q1
CPU
COPYRIGHT © 1998 CANON INC.
DADF controller PCB
SMON
Drive
circuit
SDIR
SMPWM
Figure 2-267
CANON DADF-A1 REV.0 DEC. 1998 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 2 BASIC OPERATION
Pick-up motor
J12-1
J12-2
M1
2-43