e-STUDIO281c/351c/451c © 2005 - 2008 TOSHIBA TEC CORPORATION All rights reserved
DEVELOPER UNIT
12 - 14
12.6 High-Voltage Transformer Output Control Circuit
Developer bias is supplied from high-voltage power supply to the developer sleeve and the toner image
on the developer sleeve is transferred onto the photoconductive drum.
A color developer bias and a black developer bias are output separately.
Each developer bias consists of DC and AC which has an independent ON/OFF control. At DC, D/A
converter adjusts the level of output value in both color and black modes since each mode has a differ-
ent control condition.
Fig. 12-10
• Outputs adjustment value of the developer bias (DC) in the NVRAM to the gate array.
↓
• Outputs control voltage data from the gate array to the D/A converter.
↓
• Analog conversion by the D/A converter.
↓
• Outputs control voltage Vc to the developer bias transformer.
↓
• The developer bias transformer generates output voltage proportional to the control voltage Vc by
ON signed.
* Adjustment of the control voltage Vc (change of adjustment data) is performed in the adjustment
mode.
Engine
CPU
D/A
converter
High-voltage
transformer
Gate array
#2
KCDVDON
KDVAON
CDVAON
KDVVR
CDVVR
Photoconductive
drum
Black developer
sleeve
Color developer sleeve
NVRAM
To Next Page
Loading...
