Flow Of Sync Signals - Canon Image Reader-A1 iR5000i Service Manual

2.2 Flow of Sync Signals

[1] The BD signal goes '0' when laser light is detected.
[2] A phase matching is conducted with reference to the printer, and sync signals are gener-
ated.
[3] Using the printer sync signal, image data is read from the image memory.
[4] Video signals are generated.
[5] The 2-pixel parallel signal is converted into a 1-pixel serial signal.
[6] The laser drive signal drives the laser in response to the video signals.
BD PCB
Laser
driver
PCB
E100
It is indicated if the BD signal is not detected within a specific period of
time after the laser has been turned on.
COPYRIGHT © 2001 CANON INC.
J2701
J120
1 4
Sync
GND
2 3
signal
BD* [1]
3 2
generation
5V
4 1
[2]
J117
J2502
Serial/
LD [6]
parallel
conversion
[5]
DC controller
PCB
F03-202-01 Flow of Signals
2000 2000 2000 2000 CANON iR5000i/iR6000i REV.0 JUNE 2001
CHAPTER 3 LASER EXPOSURE SYSTEM
J1015
J122
PSYNC[3]
A20 A21
J1015
J122
VIDEO [4]
Memory
control
Control unit
3-5 P