Lexmark W820 - Components Attached to or Associated with the Mcu Pwb

1-18 Service Manual
4025-XXX
Components attached to or associated with the MCU PWB:
1. I/O PWB
Interface between the MCU PWB and most of the printer components.
2. Low Voltage Power Supply
Converts AC line voltage to +5VDC and +24VDC.
3. ESS PWB
Connected to the MCU PWB. The interface between the print engine and the host
computer. The ESS processes the raw video data sent by the host computer.
4. Control Panel
Connected to the MCU PWB, the Control Panel displays status information sent from
the MCU PWB and ESS PWB.
5. AC Driver PWB
Switches 110VAC to the two Fuser Heat Lamps. Fuser temperature sensors are
connected to the AC Drive PWB. The AC Drive PWB sends the temperature
information to the I/O PWB, which sends the information along to the MCU PWB.
6. High Voltage Power Supply
Converts +24VDC received from the I/O PWB to several high voltages that are
required by printer xerographics.
7. PSHV-R2
Converts +24VDC received from the I/O PWB to the Fuser bias voltage.
8. Toner Sensor
Magnetic sensor that monitors the CRU toner level.
9. CRU
Drum usage information that is stored in the CRU.
10. Printhead
The SOS (Start of Scan) Sensor, the Printhead Motor, and the Laser Diode.
11. Main Motor
Provides most of the mechanical drive for the printer.
12. Drum Motor
Provides drive for the CRU.
13. Fuser Fan
Cools the Fuser area.
14. Feed Clutch
Transmits Main Motor drive to the Tray 1 Feed Rolls.
15. Registration Gate Clutch
Transmits Main Motor drive to the Registration Rolls.