Hvps (High Voltage Power Supply) Section - Panasonic KX-MB771GR Service Manual

KX-MB771GR

6.15. HVPS (High Voltage Power Supply) SECTION

6.15.1. HVPS SPECIFICATION
Charge (CHG)
Output Characteristics Constant current
Nominal Output Voltage 4.35KV
Nominal Output Current 200±15µA
(19.4MΩ)
Load Range 18.1MΩ~20.6MΩ
Constant Current 4.1~4.6KV
Range
As for the developing voltage, the DC voltage and AC voltage are overlapped and output from an output terminal.
There is one terminal for transcription output and + and - are switched to be output.
6.15.2. CHG-BIAS (Charge BIAS)/GRID/ UNIT
When IC300 turns on the transistor Q506, CHG REM becomes "L", and Charge BIAS (200µA) is output from CHG OUTPUT.
GRID BIAS is generated by the current flowing in the GRID circuit via charge wire and GRID.
Grid Developing DC
Constant voltage Constant voltage
475±10V 230V±15V
(50~300V)
PWM20%
300MΩ/220pF
200µA 0.73µA
----- 100MΩ~2000MΩ
----- -----
52
Developing AC Transfer (TRA) -
Constant voltage Constant current
(Variable)
330V±15Vp-p 100MΩ
34KHz (-1.48KV)
-14.8µA±1µA
----- (0µA~25µA)
PWM 35%
----- 33.8MΩ~284MΩ
----- -0.5KV ~ -4.2KV
Transfer (TRA) +
Constant voltage
785V±100V
1000MΩ
(0.8µA)
10MΩ~1000MΩ
-----