Brother HL-3450CN Service Manual page 83

CHAPTER 4 STRUCTURE OF SYSTEM COMPONENTS
<Layout & Function of the Electrical Parts>
(1) Print PCB (Refer to Fig. 4-29.)
No.
1
2
3
4
5
6
7
8
9
10
Name
Video controller PCB
Engine controller PCB
(MCTL PWB)
Control panel PCB
(Panel PWB)
LDU PCB
PDU PCB
Erase lamp
IOD1 PWB
IOD2 PWB
DC power supply
(LVPS) PCB
High-voltage power
supply (HVU) PCB
Function
To receive the print data from the host computer,
convert it into image data and then send the
printing image data to the MCTL PWB.
To control the sequence of processes of the
printer: Fusing Temperature Control, Laser Output
Control, Control Panel Indications, Toner Empty
Sensing Control, Error Processing Control,
Interface Control.
To display the printer's operation status and
support the control panel switches.
To control the drive and output to the laser diode
in the scanner unit.
To sense the emission of the laser diode and the
beam position in the scanner unit.
To discharge the OPC belt with the LEDs.
To send the signals from the sensors to the MCTL
PWB, and to drive the outputs from the MTCL
PWB to the motors, clutches and solenoids.
- Ditto -
To provide the printer with the power for printer
control.
To provide the printer with the high voltage power
supplies necessary for the printing process.
4-30