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ViewSonic Corporation
Confidential - Do Not Copy
VG1921wm-2
21
4.8 Key Parts Pin Assignment
4.8.1
IC802 (TOP245Y or TOP246Y, Power Control IC)
Pin
Symbol
I/O
Description
1 C I
Control
2 L I
Line
Sense
3
X
I
External Current Limit
4
S
O
Source of MOSFET(GND)
5 F I
Frequency
6
D
I
Drain of MOSFET
4.8.2 IC501 (OZ9938GN, CCFL inverter controller IC)
Pin No.
Symbol
I/O
Description
1 DRV1 O
Drive
output
2
VDDA
I
Supply voltage input
3
TIMER
I
Timing capacitor to set striking time and shut down delay time
4 DIM I
Analog dimming or Internal LPWM dimming or external PWM
pulse input for dimming function
5
ISEN
I
Current sense feedback
6
VSEN
I
Voltage sense feedback
7
OVPT
I
Over-voltage/over-current protection threshold setting pin
8 NC
9 NC
10
ENC
I
ON/OFF control of IC
11 LCT I
Timing capacitor to set internal PWM dimming frequency and
also a pin for analog dimming selection
12
SSTCMP
I
Capacitor for soft start time and loop compensation
13
CT
I
Timing resistor and capacitor for operation and striking frequency
14
GNDA
Ground for analog signals
15 DRV2 O
Drive
output
16
PGND
Ground for power paths
4.8.3
U105(TSUM56AL-1)
Pin
Symbol
I/O
Description
1 NC
Not
connected
2 GND
Ground
3 NC
Not
connected
4 NC
Not
connected
5 GND
Ground
6 NC
Not
connected
7 NC
Not
connected
8 AVDD_DC
I ADC
Power
9 NC
Not
connected
10 NC
Not
connected
11 GND
Ground
12 NC
Not
connected
Summary of Contents for VG1921wm-2
Page 5: ...ViewSonic Corporation Confidential Do Not Copy VG1921wm 2 2 4 Handling and Placing Methods...
Page 6: ...ViewSonic Corporation Confidential Do Not Copy VG1921wm 2 3...
Page 35: ...Disassembly Procedure ViewSonic Corporation Confidential Do Not Copy VG1921wm 2 32...
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Page 51: ...ViewSonic Corporation Confidential Do Not Copy VG1921wm 2 48...
Page 61: ...ViewSonic Corporation Confidential Do Not Copy VG1921wm 2 58 11 PCB Layout Diagrams...
Page 62: ...ViewSonic Corporation Confidential Do Not Copy VG1921wm 2 59...