Ricoh K-C3.5L Service Training page 30

Drum
LDD
Slide 30
The CCD generates an analog video signal. The SBU (Sensor Board Unit) converts the
analog signal to an 8-bit digital signal, then it sends the digital signal to the BICU board.
The BICU board can be divided into three image-processing blocks: the IPU (Image
Processing Unit), FCI (Fine Character Image), and VCU (Video Control Unit).
IPU: Auto shading, filtering, magnification, scanner gamma correction, ID gamma
correction
VCU: Printer gamma correction, LD print timing control and laser power PWM control
FCI (inside the VCU): Smoothing
Note: The IPU and VCU are contained in the same IC called SCRATCH on the BICU.
Image Processing Circuit
SBU
LSD
VCU
LD
Driver
FCI
BICU
Data comes to the BICU board from three sources.
Scanner and SBU, Fax controller & Printer controller
See the notes section below for more details.
Memory
Control
DRAM
IC
IPU
SCN
30
Model K-C3.5L
PRN
GDI and
GW
Controller