Specifications

2001 CANON INC. 2000 2000 2000 2000 CANON DADF-J1 REV.0 MAR.2001

CHAPTER 2 OPERATIONS AND TIMING

2-33

2.4.5 Controlling the Pickup Motor (M3)

The following is a control circuit of the pickup motor (M3). The pickup motor is a 4-

phase stepping motor, and the circuit is used for the following:

• Turning on/off the motor.

• Controlling the direction of rotation of the motor.

• Keeping the motor on hold.

F02-204-11

The CPU (Q1) on the ADF controller causes the motor hold signal (PICKHOLD) to go

‘0’, and applies +24R to drive the pickup motor. At the same time, the CPU sends the phase

control signal (PICKA, PICKB) to the motor driver (Q24), which in response controls the

output timing of pulse signals according to the phase signal it receives, switching the direc-

tion of rotation of the pickup motor.

If the CPU does not generate the phase control signal (PICKA, PICKB), the motor hold

signal goes ‘1’, applying +5R for retention to the pickup motor to keep the spindle of the

motor on hold.

E410

Indicates a fault in the pickup motor (M3).

Indicates a fault in the pickup motor height sensor (PI8).

Indicates a fault in the pickup roller height sensor (PI9).

Indicates a fault in the pickup roller home position sensor (PI7).

Indicates a fault in the ADF controller PCB.

Q24

+5R+24R

Q53

CPU

J11

PICKHOLD

PICKA

PICKB