Controlling The Intensity Of The Scanning Lamp; Outline; Operations - Canon CLC5000 Service Manual

CHAPTER 2 NEW FUNCTIONS

1.5 Controlling the Intensity of the Scanning Lamp

1.5.1 Outline

The machine's scanning lamp is a halogen lamp.
The following figure shows the circuit used to control the intensity of the scanning lamp,
and the circuit has the following functions:
1. Turning on and off the scanning lamp
2. Detecting the activation of the scanning lamp
3. Controlling the intensity of the scanning lamp
• The intensity of the scanning lamp is controlled to a specific level even when the volt-
age of the power supply fluctuates.
AC
power
supply
J1306 J450
B4
LAERR
B1
LAON
B2
LACNTL
B7
LAON-S*
B5
TIM-RST

1.5.2 Operations

1. Turning On and Off the Scanning Lamp
When LAON is '0', the lamp regulator drive circuit is off, and the intensity connector
circuit is also off, consequently keeping the scanning lamp (LA1) off.
When LAON is '1', on the other hand, the lamp regulator drive circuit goes on to turn
on the intensity control circuit, consequently turning on the scanning lamp (LA1).
2-6
Rectification
circuit
J9
FU1
4
1
24V
7
Lamp
regulator
10
drive
circuit
9
24V
Error
latching
circuit
4
6
COPYRIGHT © 2001 CANON INC.
Switching
circuit
PWM
Lamp ON
detection
Timer
circuit
Lamp regulator
F02-105-01
2000 2000 2000 2000
Scanner
thermal
switch 1
(TP4)
+
1
-
3
Scanning lamp
(LA1)
circuit
CANON CLC5000 REV.0 JAN. 2001
Scanner
thermal
switch 2
(TP5)