High-Voltage Output Control Circuit; General Description - Toshiba e-STUDIO167 Service Manual

11.4 High-Voltage Output Control Circuit

11.4.1

General description

In this equipment, the high-voltage generation circuit is included in the switching regulator. It is con-
trolled by the ON/OFF signal of each bias output from the ASIC on the MAIN board and reference volt-
age Vc of each bias output from the SoC via the D/A converter. It generates the output current and
voltage of each bias according to the +24VCOV-OFF input from the low-voltage generation circuit of the
switching regulator.
MAIN board
Digital data
SoC
HVCLK-0
Adjustment
value
Flash ROM
HVTM-0
HVTAC-0
HVTT-0
ASIC
HVTSP-0
HVTGB-0
HVSDWN-0
© February 2007 TOSHIBA TEC CORPORATION All rights reserved
HVMVR-1
HVDTR-1
D/A
HVTVR-1
converter
HVSAV-1
Analog data
(Reference voltage: Vc)
Fig. 11-3
11 - 5
Switching regulator
[Low-voltage section]
+24VCOV-OFF +24VCOV-OFF
[High-voltage section]
Charger bias
Needle
electrode
Needle electrode
bias
Grid bias
Grid
Developer bias
Developer
AC
Magnetic roller
Developer
DC
Transfer
Transfer charger
bias
Separation
Separation charger
bias
Transfer guide
Transfer guide
bias
Leakage detection
e-STUDIO167/207/237
DRUM RELATED SECTION
11