User manual

95.08.23.11.29
Color LaserWriter 12/600 PS Basics & Theory 1–60
High-Voltage Control: Outline
The high-voltage power supply of the printer is controlled by the high-
voltage control IC (IC1003). In serial communication with the
mechanical controller, IC1003 applies voltages to the primary charging
roller, developing cylinder, transfer drum, attraction roller, discharge
roller, separation discharge assembly, and upper fuser roller in response
to the instructions from the mechanical controller.
The primary charging roller, the developing cylinder, and the separation
discharge assembly are charged with superimposed DC and AC volt-
ages. The transfer drum is charged with the positive DC voltage. The
attraction roller is charged with negative DC voltage being superim-
posed onto the transfer voltage. The discharge roller is charged with
AC voltage being superimposed onto the transfer voltage. The separa-
tion discharge assembly normally is charged only with DC voltage and
is charged with AC voltage superimposed on DC voltage only in a low
temperature and low humidity environment. The upper fuser roller is
charged with DC voltage.
Mechanical Controller Board
DC Controller Board
AC Voltage
Generation Circuit
DC Voltage
Generation Circuit
Primary Charging
Roller Voltage Circuit
AC Bias
Generation Circuit
DC Bias
Generation Circuit
Developing Bias
Generation Circuit
Attraction Roller Voltage
Generation Circuit
Discharge Roller Voltage
Generation Circuit
Transfer Roller Voltage
Generation Circuit
High-Voltage Control (IC 1003)
High-Voltage Power
Supply Board
AC Voltage
Generation Circuit
DC Voltage
Generation Circuit
Separation Voltage
Generation Circuit
High-Voltage
Separation Bd.
Developing
Cylinder
Primary
Charging
Roller
Upper Fuser
Roller
Separation
Discharge
Assembly
Discharge Roller
Attraction
Roller
Transfer Drum