Toshiba e-studio182, Service Manual

Page: 243 / 258

14
© 2009 TOSHIBA TEC CORPORATION All rights reserved e-STUDIO182/212/242
POWER SUPPLY UNIT
14 - 1
14. POWER SUPPLY UNIT
14.1 Construction
The power supply unit consists of the AC filter, insulated-side DC output circuit, high-voltage output
circuit, and heater lamp control circuit.
1. AC filter
Eliminates noise from the outside and prevents the noise generated by the equipment from leaking
to the outside.
2. DC output circuit (Low-voltage output circuit)
Converts AC voltage input from outside to DC voltage and supplies it to each electric part. The DC
voltage is divided into the following two lines.
a.Main switch line: Power supply used in the entire equipment during the image forming process.
Six kinds of voltage (+5V, +5VB, +12V, -12V, +24V and +24VDF) are out-
put when the main switch of the equipment is turned ON.
b.Cover switch line: Power supply used in the entire equipment during the image forming process.
It is supplied via the cover switch. This voltage (+24VCOV-OFF) is output
only when both the main switch of the equipment and the cover interlock
switches are turned ON (when the front and ADU covers are closed).
* When the equipment is in Energy Saving Mode (Auto Shut Off Mode), only the +5VB for the main
switch line is supplied.
3. High-voltage output circuit
Generates the output currents/voltages for the charger, developer, transfer and separation biases,
based on the +24V voltage which is generated by the DC output circuit. For details of the high-
voltage output circuit, see the following.
P.10-5 "10.4 High-Voltage Output Control Circuit"
4. Heater lamp control circuit
TRC (Triac) is driven by the heater control signal (HTON1B/HTON2B) from the MAIN board and
then AC power is supplied to each heater lamp (center and side) in the fuser unit. For details of the
heater lamp control circuit, see the following.
P.12-6 "12.5 Fuser Unit Control Circuit"