14 June, 2002
PCBS
6-43
D
e
tailed
D
escr
iptions
VPL (Video Processing LSI).
A sub-chip of the fax engine that implements video
processing with these internal blocks:
•
VPM (Video Processing Module). Scanning control and image processing.
•
LIF (Laser Interface). Printing control and image processing.
•
Analog/Digital Convert. Modem operation.
Thermistor (Thermistor Control Circuit)
. Receives and processes the data from
the contact thermistor on the hot roller. This data is used to control the temperature
of the fusing unit.
Fusing (Fusing Lamp)
. Located inside the hot roller, the fusing lamp heats the hot
roller. The temperature of the fusing lamp is monitored by a contact thermistor and
the temperature of the hot roller is controlled by switching the lamp off and on.
LDDR (Laser Diode Driver).
The interface for the laser diode driver. The driver
switches between the 1200 dpi and 600 dpi modes.
Video Circuit (Video Processing Circuit)
. Interfaces the VPL (Video Processing
LSI) and CIS (Contact Image Sensor).
Color CIS (Color Contact Image Sensor).
Consists of a strip of photo diodes to
illuminate the original, and a strip of phototransistors covered by a row of self-
focusing lenses. The CIS contacts the original directly, so the size of the scanner
unit can be reduced.
CIOP (Communications and I/O Processing).
The sub-chip of the fax engine that
controls communication and the I/O circuits.
P/P (Power Pack and Power Pack Control Circuit
. Interfaces the VPL (Video
Processing LSI) and the high-voltage power supply unit (power pack). Also
receives feedback and implements PWM (Pulse Width Modulation) control that
determines the duration width (duration) of the laser diode pulse that creates the
latent image on the drum. This is the high-voltage power supply unit.
PFU (500-sheet Paper Feed Unit)
. Provides the interface for the optional Paper
Feed Unit Type 510.
Plotter Driver
. Performs the following functions:
•
Drives the main motor and the polygonal motor
•
Processes output from the laser synchronization detector, exit sensor, paper
near end sensor, paper end sensor, registration sensor, and interlock switch
•
Controls the by-pass feeder, paper feed and registration clutch, cooling fan, lift
motor drive circuits, and all sensors related to printing
Plotter
. The print engine of the machine.