Power Supply; Engine Control Board - Tektronix Phaser 600 Service Manual

5
Theory of Operation

Power supply

Engine control board

5-12 Phaser 600 Color Printer
The power supply provides the DC power source for the printers electronics and
motors. It also provides the power for the printhead's heaters and piezo-electric
crystals.
+5 volts. +5 volts powers the printer's digital logic circuits.
+12 volts. +12 volts runs the printer's fan, stepping motors, ink loader
motors and solenoids.
-12 volts. -12 volts is used for the print's comparator circuits.
+40 volts. +40 volts drives the X-axis, Y-axis, and fuser motors, heaters
and air pump.
+HV and - HV.
These adjustable voltages drive the printhead's
piezo-crystals elements.
There are no field adjustments necessary on the power supply except for
printhead drive voltages.
The engine control board is responsible for data processing of information
provided by the image processor board and of the inputs from the printer's
sensors.
The engine control board features comparators to check for over-temperature
conditions and for sensing the input from the printhead's left and right paper
edge sensors.
The engine control board contains the drivers for the X-axis, Y-axis and fuser
motors, the printhead heaters, and the fans.
Lastly, the engine control board contains the A/D converters for controlling the
printhead temperatures, monitoring power supply output, ink levels in the
printhead and the fuser's temperature.