Main Motor (M1) Control Circuitry - Canon NP6251 Service Manual

D. Main Motor (M1) Control Circuitry
1. Outline
Figure 2-107 is a block diagram showing the main motor control circuitry, which has
the following functions:
Turning off and on the main motor.
Controlling the main motor to a specific speed.
The main motor is a DC motor equipped with a built-in clock pulse generator which
generates clock pulses (MMCLK) when the motor rotates in numbers corresponding to
the revolution.
The main motor control PCB uses these clock pulses to ensure that the motor rotates
at a specific speed at all times.
These clock pulses are also sent to the DC controller PCB after its frequency is
divided to 1/4.
J602
DC controller
PCB
J111
B4 M1ON
Q156
Master
B3 M1FG 2
COPYRIGHT © 1997 CANON INC.
Main motor control PCB
Switch
1
circuit
Reference
signal
generator
circuitry
Phase
comparison
Frequency
comparison
1/4 division
Figure 2-107
CANON NP6350/NP6251 REV.0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
Phase
comparison
Motor driver circuit
signal
Mixing
Frequency
comparison
signal
CHAPTER 2 BASIC OPERATION
Hall IC
U
V
Clock pulse
generator
Main
W
Rotor
motor
MMCLK
2-11