Tektronix Phaser 550 Service Manual page 97

5
Theory of Operation
The toner cartridges
Four toner cartridges, black, yellow, cyan and magenta, contain the primary
color toners that are sequentially transferred onto imaging unit's
photoconductive belt depending on where the laser exposed the belt.
Subsequently, the toner is transferred to the imaging unit's accumulator belt
from which it is transferred to a sheet of media.
The fuser
The fuser permanently bonds the toners to the media through a combination of
heat and pressure.
The engine boards
Working as the "brains" of the print engine, the engine control board coordinates
all printer functions. It contains the microprocessor and ROM that control
printer operations. The engine driver board drives the printer's motors and
solenoids.
The power supply
The power supply provides regulated DC power source for the printer's
electronics, motors and high-voltage chargers and bias rollers.
The mechanicals
Mechanicals include the motors and solenoids that drive the belts and rollers of
the printer.
The image processor board
The image processor board converts the image data from the host computer into
a raster format for the print engine.
Service Manual 5-3