Canon 3260 manual Figure below shows the scanner motor control circuit

CHAPTER 2

C. Scanning System

Figure below shows the scanner motor control circuit.

DC controller PCB

	+5V	+24VA
IC201		J207-7
(CPU)
	+5V	-1
XT1/P07	73	-2	/SCNRDY
	+5V
IC202
(G.A.)		-3	/SCND
DB22	52
SCNCLK	54	-5	/SCNCLK
X1AO	70	-4	GND
	X202	-6	24VGND
X1AI	71
		Figure 2-3-4

J18

-1 J1-1

-7 -7

-6 -6

-5 -5

-3 -3

-4 -4

-2 -2

Scanner motor

M1

M

The scanner motor is a three-phase, eight-pole DC brushless motor with a HALL element. It forms a unit with the scanner driver, which controls the scanner motor rotation at a constant speed.

When the printer is turned ON, the oscillation frequency of the crystal oscillator (X202) is divided by the gate array (IC202), and the /SCNCLK signal is sent to the scanner driver.

When the /PRNT signal sent to the CPU (IC201) on the DC controller becomes “L”, the CPU sets the /SCND signal to “L” through the gate array. When it goes “L”, the scanner driver rotates the scanner motor using the SCNCLK signal. When the scanner motor reaches its prescribed speed, the scanner driver sets the SCANNER MOTOR READY signal (/SCNRDY) signal to “L”.

The CPU on the DC controller PCB monitors the /SCNRDY signal to make sure that the scan- ner motor runs at the correct speed.

The CPU notifies the video controller of a scanner failure in the following cases:

a.When the /SCNRDY signal does not become “L” within 30 seconds after the scanner motor starts rotation.

b.When the /SCNRDY signal goes “H” for 1.5 continuous seconds after going “L.”

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