Panasonic UF-6300 Service Manual page 197

SHINE
Fuser Lamp Drive Circuit
The Fuser Lamp is powered by 100 VAC (200 VAC). It is driven by the LVPS and controlled by the nSSR
signal from the SC PC Board. When the CN103, Pin11 (nSSR) on the LVPS goes LOW, the Fuser Lamp
turns ON. This lights up the PC102 LED and activates the TRC100 photo-triac, and VAC 115 VAC is sent
to the Fuser Lamp. The time at which TRC100 is actually activated depends on the 100 VAC (200 VAC)
sine wave. When the cross-voltage for Pin 6 and Pin 4 of PC102 is other than 0 Volts (sine wave
exceeds 0 volts), PC102 inhibits the activation of the triac and turns ON the Fuser Lamp.
nSSR
11 11 CN103
SC PCB
Fuser Temperature Control Circuit
The fuser temperature is controlled by IC1 on the SC PC Board, which contains A/D (Analog/Digital)
converters ANI0 to ANI7. The Fuser Temperature Control Circuit uses A/D converter, ANI1. When the
PC001 drive current is transmitted from the SC PC Board to the PSU (LVPS), the Fuser Lamp turns ON.
IC32 is a comparator with open output at pins 1 and 7 and is used as an abnormal temperature detection
circuit. IC32, pin 7, has a high impedance when Q44 is activated, turning ON the Fuser Lamp.
An abnormal temperature is detected when the VTH voltage level becomes higher than V+, forcing IC32,
pin 7 Low and deactivating Q44.
Abnormally low and high temperatures, as well as Thermistor release status, are detected by IC1 (CPU)
programming.
IC3
Laser Printer Motor Drive Circuit Block Diagram
+24V
PC102
1
2
Fuser Lamp Drive Circuit Diagram
+24 VM
CN54
3 MMnA
Motor 1 MMpA
Driver
6 MMnB
IC38
4 MMpB
TRC100
R111
6
2
4
3
C109
1
R112
L301
197
Pulse
Motor
L101
R111
C108
Fuse
CN102
1
CN102
2
LVPS
2
1
H
Fuser Lamp
Thermal Fuse
Thermostat