Xerox WorkCentre Pro 412, Service Manual

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Circuit Description
WorkCentre Pro 412
Launch Issue
5-18
August 2001
5-3 Scanner
5-3-1 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 the number of motor steps.
CCD
Contact Image Sensor improves productivity and allows a compact design.
This machine uses a color CCD.
• Minimum scan line time for one color: 5mS.
• Light source power: +12V.
• Maximum pixel frequency: 6 MHz.
• Effective sensor element: 5340 X 3.
• Clamp level: 0.7 to 0.8V.
• Bright output: min. 0.8V.
IRQ
[ AFE]
12-bit
A/ D converter
Shadi ng
C orrectio n
Enlarge men t
/ Redu ction
SRAM
8 192 x 8
( 2l ine)
Imag e
Processing
M o dule
D M A
Interface
CIP3
Register
CPU I/F
Mod ule
Vp eak
Contro l
M o to r
Con tro l
AIN
AD C_REFT
ADC _REFB
PI_TG
PI1
R_LED,
G _LE D,
B _LE D
Gam ma
C orrectio n
SRAM_A[ 15:0]
SRAM_D[ 15: 0]
SRAM_nRD
SRAM_nWR
A [ 5: 0] D [ 15: 0] nCS nRD nWR nXDREQ nXDACK
TX_A, B
nTX_A, B
TX_EN1, EN2
Sen so r
Interface
Shadi ng
Acqu isitio n
SRAM
1 024 x 8
( R/G/ B)
SRAM
4096 x16
(2 line )
SRAM
256 x 8
PI2
EXT SRAM
Interrupt
Contro l
Vertical
D ecim ation
SRAM
1 024 x 8
DUOIP2 Block Diagram