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:
q
Turning off and on the main motor.
w
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.
Figure 2-107
DC controller
PCB
Q156
Master
Main motor control PCB
Main
motor
Rotor
Hall IC
V
W
Motor driver circuit
MMCLK
Frequency
comparison
signal
Phase
comparison
signal
Mixing
Switch
circuit
Phase
comparison
Frequency
comparison
Reference
signal
generator
circuitry
1/4 division
B3 M1FG 2
B4 M1ON
1
J602
U
J111
Clock pulse
generator
COPYRIGHT © 1997 CANON INC. CANON NP6350/NP6251 REV.0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 2 BASIC OPERATION
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