Circuit Description Of Cis Unit - Sharp FO-3150 Service Manual

FO-3150U/C

[6] Circuit description of CIS UNIT

This CIS unit picks up optical information from the document, converts it
into an electrical (analog) signal and it to the control PWB.
1. Block diagram
SH
CISCLK
VLED
GLED
+5V
GND
OUTPUT CIRCUIT
AiN
(emitter follower)
Fig. 30
CIS
SIG
Fig. 29
2. Description of blocks
(1) CIS
The IA2008-MB71B standard type of contact image sensor that con-
sists of 1728 picture elements.
Receiving two drive signal (SI,CLK) from the control PWB, the trans-
ferred photoelectric analog signal SIG is impedance converted, and the
signal AIN, is supplied to the control PWB.
(2) Waveforms
1. CLK, SI, SIG signals within the control PWB.
CLK
SI
SIG
1
5 – 25
2 3 1726 1727 1728
5 msec/line
Fig. 31