Epson ES-1200C Pro PC, Service Manual

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Operating Principles
Service
2.3.5 Image Sensor Drive Circuit
Figure 2-15 is a block diagram of the
r drive circuit. Gate array controls image
sensor operations. The sensor receives the following control signals: the signal, which drives
the main sensor’s shift transmission pulses and which transmit the signal
charges (and which are described, as and @2, in Section 2.1.1); and the reset signal, which
resets the image sensor’s output section following the reading of each pixel. The image sensor
receives these control signals, and outputs the image data as signal V. The process is illustrated in
Figure 2-16.
The image data output by the image sensor is in the form of an analog signal. This signal is passed
through an amplifying
The analog signal output from the amplifier is passed into the lo-bit A/D converter and converted
into 10-bit digital data. This data is sent to gate array
Details of subsequent image
processing may be found in Section
2.3.1.
The original document must be illuminated to be
read.
scanner uses fluorescent lamps for this
purpose. These lamps by gate array
gate array switching
in order to maintain the proper radiation
-
.
Vo
AMP.
10 bits data
VE
● ADO-9
—
SHOUT
CK1O 4
SH
CKIE I EVEN
4
CLK
2EVEN
4
●
RSEO
CCD
GA
(iCl)
Scanner head
B027 MAIN Board
Figure 2-15. Image Sensor Drive Circuit
1
2-12 Rev.
.-. ,
,