Xerox WorkCentre XK50cx, Service Manual

Page: 37 / 109

4-10
Circuit
4-1-3 System Memory
System memory consists of 1MB flash memory,
8MB DRAM and 2MB DRAM (back-up). Flash
memory, DRAM are selected by each CHIP
SELECT (/ROMCS, /RAS0, /RAS 1, /LCAS, /UCAS),
and data is accessed half word (16bits) by half
word.
4-1-4 Scanner
SUMMARY
This flat-bed type device to read manuscripts has
600dpi CCD as an image sensor. There is one
optical sensor for detecting CCD home position and
Scan-end position. The home position is detected by
a optical sensor which is attached to the CCD
Module. The Scan-end position is calculated by
numer of motor step.
SCAN RESOLUTION
– Draft : 300 x 600 (H x V)
– Normal : 600 x 600 (H x V)
– Best : 600 x 600 (H x V)
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 : +11.75V
– Maximum Pixel frequency : 3MHz
– Effective Sensor Element : 5340 X 3
– Clamp Level : 0.7~0.8V
– Bright Output : MIN 0.8V
Fig.4-1-9 DUOIP2 Block Diagram