Panasonic UF-490 Service Manual / Other ▷ View online
17
1.1.6.
PNL PC Board
The PNL PC Board Assembly consists of the Panel CPU, LCD Module with BackLight, LED, A-Point
Sensor, B4-Width Sensor (Specific Countries only) and Key Switches.
Sensor, B4-Width Sensor (Specific Countries only) and Key Switches.
The Panel CPU is interfaced to the main CPU on the SC PC Board. The CPU controls LCD and LED by the
command signals from the main CPU, which also detects the signals of Key Switches and Sensors.
command signals from the main CPU, which also detects the signals of Key Switches and Sensors.
Energy Saver (Sleep Mode)
The Main Power Supply is controlled by the Energy Saver signal (nPWSAVE).
By the command signals from the Main CPU, the Panel CPU controls the Energy Saver Sleep Mode by
changing the "nPWSAVE" signal level to "Low" (Enable) or "High" (Disable).
When the A-Point Sensor is triggered or the Energy Saver Key is pressed, the Panel CPU sends the
command signal by itself (the Main CPU is sleeping in Sleep Mode), which in turn changes the "nPWSAVE"
signal to "High" level disabling the Sleep Mode.
The Main Power Supply is controlled by the Energy Saver signal (nPWSAVE).
By the command signals from the Main CPU, the Panel CPU controls the Energy Saver Sleep Mode by
changing the "nPWSAVE" signal level to "Low" (Enable) or "High" (Disable).
When the A-Point Sensor is triggered or the Energy Saver Key is pressed, the Panel CPU sends the
command signal by itself (the Main CPU is sleeping in Sleep Mode), which in turn changes the "nPWSAVE"
signal to "High" level disabling the Sleep Mode.
Panel CPU
mPD780022A (NEC)
GND
8.00MHz
32.768kHz
*RESET
XIN
Main
CPU
CPU
Panel Reset
LCD Module
LCD Control
Data
Serial I/F
Power Down
Energy Saver
Power Module Control
Buzzer Clock
Energy Saver Release
GND
LED Matrix
LED Control
LED Data Out
Key Matrix
Key Scan
Output Control
Key Input Data
XOUT
XTIN
XTOUT
B4 Width Sensor
Sensor Input
Clock Output
PWDWN
A-Point Sensor
Input Control
Energy Saver Key Input
Back Light Control
A-Point Sensor
A-Point Sensor Input
BUZ
PLC
The two data streams (LCD Data Bus, Key Scan Output) are transferred on same data bus.
*
ANI6
(nWAKUP)
(nPWSAVE)
Energy Saver LED Control
Panel CPU
(SC PCB)
(Specific Countries only)
18
The machine will recover from Sleep Mode by the following conditions.
1. Press the Energy Saver Key
2. A-Point Sensor Actuated (Document is set on the ADF)
3. Ringing Signal Detected
4. Off-Hook Detected (Handset, External Telephone)
1. Press the Energy Saver Key
2. A-Point Sensor Actuated (Document is set on the ADF)
3. Ringing Signal Detected
4. Off-Hook Detected (Handset, External Telephone)
Main
CPU
CPU
V850
(IC1)
Panel
CPU
(IC2)
PNL PCB
A-Point
Sensor
Sensor
nAPNT
+5VP
Set Document
+3.3V
SC PCB
PSU
+5VP
+5V
CI Off-Hook
Detect
Circuit
Circuit
LINE
TEL
pCTON
+5VP
+5V
Signal Detect
nPWSAVE
nPWOFF
nWAKUP
19
1.1.7.
Laser Printer Drive Circuit
1.Motor Drive Circuit
The Scanner/Printer Motor is a 4-phase uni-polar PM-type step motor. The step signals (A to nB) are
transmitted to IC26 (the Chopper Drive Circuit) by SHINE(IC3). The chopper current is determined by
the voltage at IC26, Pin3 and Pin13. The Motor has two speeds, Slow and Constant. The Motor is
powered by a +24 VDC supply. When the interlocks are open, the +24 VDC supply is cut off and the
Motor stops rotating.
transmitted to IC26 (the Chopper Drive Circuit) by SHINE(IC3). The chopper current is determined by
the voltage at IC26, Pin3 and Pin13. The Motor has two speeds, Slow and Constant. The Motor is
powered by a +24 VDC supply. When the interlocks are open, the +24 VDC supply is cut off and the
Motor stops rotating.
Pulse
Motor
Scanner / Printer Motor Drive Circuit Block Diagram
SHINE
IC3
+24 VM
1
3
4
6
CN53
Motor
Driver
IC26
A
nA
B
nB
20
2. Fuser Lamp Drive Circuit
The Fuser Lamp is powered by 115 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 PC001 LED and activates the CR001 photo-triac, and 115 VAC is sent to the Fuser
Lamp. The time at which CR001 is actually activated depends on the 115 VAC sine wave. When the
cross-voltage for Pin 6 and Pin 4 of PC001 is other than 0 Volts (sine wave exceeds 0 volts), PC001
inhibits the activation of the triac and turns ON the Fuser Lamp.
the SC PC Board. When the CN103, Pin11 (nSSR) on the LVPS goes LOW, the Fuser Lamp turns ON.
This lights up the PC001 LED and activates the CR001 photo-triac, and 115 VAC is sent to the Fuser
Lamp. The time at which CR001 is actually activated depends on the 115 VAC sine wave. When the
cross-voltage for Pin 6 and Pin 4 of PC001 is other than 0 Volts (sine wave exceeds 0 volts), PC001
inhibits the activation of the triac and turns ON the Fuser Lamp.
11
11
CN103
+5V
R221
3
2
1
PC001
nSSR
R002
CR001
2
3
1
1
C002
R001
C001
3
1
CN102
H
CN102
Fuser Lamp
Fuse
Thermostat
Thermal Fuse
3
SC PCB
4
(Power Supply Unit)
Fuser Lamp Drive Circuit Diagram
L001
Click on the first or last page to see other UF-490 service manuals if exist.