Service manual

Circuit Description
3-19
3-3 Scanner
3-3-1 SUMMARY
This flat-bed type device to read manuscripts has 600dpi CCD as an image sensor. There is one optical sen-
sor for detecting CCD home position and Scan-end position. The home position is detected by a optical sen-
sor which is attached to the CCD Module. The Scan-end position is calculated by numer of motor step.
CCD
Charge Coupled Device improves productivity and allows a compact design.
This machine uses a color CCD.
• Minimum Scan Line Time for One Color : 2.5mSec
• Light Source Power : +18V
• Maximum Pixel frequency : 10MHz
• Effective Sensor Element : 5340 X 3
• Clamp Level : 0.7~ 0.8V
• Bright Output : MIN 0.8V
IRQ
12-bit
A
AFE_CIP4
/ D converter
Shading
Correction
Enlargement
/Reduction
SRAM
8192
x
8
(2line)
Image
Processing
Module
DMA
Interface
CIP4
Register
CPU I/F
Module
Vp eak
Contro l
Mo to r
Con tro l
AIN
AD C_REFT
ADC_REFB
PI_TG
PI1
Gamma
Correction
SRAM_A[ 15:0]
SRAM_D[15:0]
SRA M_nRD
SRA M_nWR
A[5:0] D[15:0]nCS nRD nWR nXDREQ nXDACK
TX_A, B
nTX_A, B
TX_EN1, EN2
Sensor
Interface
Shading
Acqu isitio n
SRAM
1024
x
8
(R/G/B)
SRAM
4096
x
16
(2 line)
SRAM
256
x
8
PI2
EXT SRAM
Interrupt
Contro l
Vertical
Decimation
SRAM
1024
x
8
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