Dc Controller (Dcnt); Outline; Operations - Canon MF8100 Series Service Manual

2.6.2 DC Controller (DCNT)

2.6.2.1 Outline

The DCNT Board, which is controlled by the CPU in it, controls operation sequences for the printer.
When the power is turned on and DC power is supplied from the power supply unit to the DCNT Board PCB, the CPU starts to control the operations of the printer.
Then, when the printer enters the standby status, the CPU drives loads such as the laser diodes, motors, solenoids, etc. based on a print command and image data
input from the interface controller.
Fixing unit

2.6.2.2 Operations

a. CPU (IC101)
A 16-bit single-chip microcomputer is used for a CPU. It has a built-in ROM and RAM. It controls the following operations according to a program stored in the
ROM:
1) Printer engine sequence control
2) Drive controls for the developing rotary motor, toner cartridge motor, fixing motor, engaging motor
3) Drive control for the cooling fan
4) Internal temperature detection thermistor control
5) Reading/writing to the non-volatile memory
b. ASIC (IC102)
The ASIC (Application Specific IC) is an IC used for interface of IC, memory, external device, etc. It controls the following operations according to the CPU:
1) Laser/scanner control
2) Control of communications with the interface controller
3) Power supply unit (fixing control circuit, low-voltage power supply circuit) control
4) High-voltage power supply PCB control
5) Drive control for the main motor
6) Sensor/switch controls
7) Clutch/solenoid controls
8) Reading/writing to the memory tag
9) 250-sheet paper feeder (option) control
c. Reset IC (IC105)
It monitors +3.3 V and resets the CPU and ASIC when the power is turned on.
d. Non-volatile memory (IC109)
It stores backup data.
oner cartridge
T
H.V.T,
× 4
Sub-H.V.T
Memory tag
Drum cartridge
Memory tag
Main motor
Switch 1
×
Sensors 8
×
Solenoids 2
×
Clutches 2
×
Power supply unit
Fixing
control circuit
AC input
+3.3V
Low-voltage
+5V
power supply
+24V
circuit
Developing
rotary motor
Toner
cartridge
motor
Fixing motor
Engaging
motor
Cooling fan
DCNT Board
/BDI
IC 102
ASIC
IC105
Reset IC
/RESET
IC109
Non-volatile memory
IC103
Developing rotary
motor driver IC
IC 101
IC104
CPU
oner cartridge
T
motor driver IC
IC 106
Fixing motor
driver IC
IC 107
Engaging motor
driver IC
Fan motor
control circuit
F-2-52
Laser/scanner unit
Scanner
motor
BD circuit
Laser driver
SCNT Board
250-sheet
paper feeder
(option)
Internal
temperature
detection
thermistor
AC line
:
: Multiple control lines
:Single control line
Chapter 2
0008-1725
0008-1726
2-37