Panasonic UF-5500, Service Manual

Page: 64 / 365

64
UF-5500 / 4500
6.15. HVPS (High Voltage Power Supply) Section
6.15.1. HVPS Specification
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 (200
µ
A) is output from CHG OUTPUT.
GRID BIAS is generated by the current flowing in the GRID circuit via charge wire and GRID.
Charge (CHG) Grid Developing DC Developing AC Transfer (TRA) - Transfer (TRA) +
Output Characteristics Constant current Constant voltage Constant voltage Constant voltage Constant current
(Variable) Constant voltage
Nominal Output Voltage 4.35KV 475±10V 230V±15V
(50~300V)
PWM20%
300M
Ω
/220pF
330V±15Vp-p
34KHz 100M
Ω
(-1.48KV)
785V±100V
Nominal Output Current 200±15
µ
A
(19.4M
Ω
)
200
µ
A 0.73
µ
A
-----
-14.8
µ
A±1
µ
A
(0
µ
A~25
µ
A)
PWM 35%
1000M
Ω
(0.8
µ
A)
Load Range 18.1M
Ω
~20.6M
Ω
----- 100M
Ω
~2000M
Ω
----- 33.8M
Ω
~284M
Ω
10M
Ω
~1000M
Ω
Constant Current
Range 4.1~4.6KV ----- ----- ----- -0.5KV ~ -4.2KV -----
H.V.P.S.(High Voltage Power Supply) Circuit Diagram
T1
T61
GRID CIRCUIT
TRA BIAS
GRID BIAS
CHG BIAS
DEV BIAS
3
5
4
2
3
5
4
2
CN1
TRA CLK
ALM
DEV CLK
CHG REM
HV P.C.B
CN505
IC300
Q501
Q504
Q506
Main P.C.B
OPC
J25
J26
P26 HVERR
TRS
DEV
CHG
J23