Panasonic UF-580 Technical Manual page 24

High Voltage Drive Circuit (Charging, Development and Transfer)
High Voltage is provided through a DC to DC converter, which changes the +24 VDC supply voltage to
-650 VDC, and output approximately 0.64 KVAC (Steady current: 200 µA) for the Charging Block. The
Developer Circuit converts the +24 VDC to between -300 VDC for the development bias, and outputs
1,500 VAC (p-p) at a frequency of 1.650 kHz to charge the toner. The Transfer Circuit changes the +24
VDC supply voltage to approximately +280 VDC (MAX) (steady current: 3 µA/-1500 VDC steady
voltage).
pCR0
pCR1
CPU
pTR0
pDRCK
Ver 2.00
3
2
Q40
3
1
2
Q39
1
2
GND
3
2
Q41
1
GND
High Voltage Drive Circuit
CN53
nCRCK 3
nCR1 4
T
C
nTR0
5
3
D
Q3
1
nDRCK 2
HVPS
SC PCB
24
UF-580/590/780/790
DX-600/800
Discharge Plate
Bias Transfer Roller
FG
Bias Charge Roller
Toner
Cartridge
Development Roller
DEC 2003