Read Section - Panasonic KX-F900 Service Manual

KX-F900
4-3. READ SECTION
(1) Function
eA document is illuminated by the LED array, and the reflections pass through the reduction-projection lens and are im-
aged on the CCD image sensor.
eThe document image is photoelectrically transferred by the CCD image sensor, and an analog image signal correspond-
ing to one line of the document is continuously output.
• The anatog image signal enters the image signal processing circuit in ASIC (ICl) and then is coverted into a digital data.
(2) Circuit Operation
[Start]
When the START/COPY/SET button is pressed, ICl pin 62 goes to a high level and IC7 is turned ON, which makes CN7
pin 2 go to a low level and the voltage applied to the LED array to turn on the LED.
F1, F2, FR and FTG signals are output to the CCD board to drive the CCD image sensor. Therefore, when the LED is
turned ON, the VIDEO (analog image signal) is output from the CCD board to CN5 pin 7.
CCD Scanner Timing Chart (1 Dot Cycle)
F1
F2
FR
VIDEO
m I
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>>1
I<< ND data valif
I
I
LED
ARRAY
1 DOCUMENT
II
CN7 *24VI
CCD
BOARD
1I-I
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IC7
Block Diagram
CN6
c 1
o2
6,8
o-
o7
+5V
R70
R71
R72
R7a
-I V,D O
t R75
R74
15
14
13
12
84
4O
62
0V
iC1
F153
F252
FR51
FTG50
AIN1
o_
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O
c
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O
"o
m
_0
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O
z
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