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ViewSonic Corporation
Confidential - Do Not Copy
VA2226w-1
6.5 IC802 (NCP1203)
Pin No. Pin name
Function
Pin Description
1 Adj
Adjust he skipping peak
current
This pin lets you adjust the level at which the cycle
skipping process takes place. Shorting this pin to
ground,permanently disables the skip cycle feature.
2 FB
Sets the peak current
setpoint
By connecting an optocoupler to this pin,the pead
current setpoints is adjusted accordingly to the
ouput power demand.Skip cycle occurs when FB
falls below Vpin1.
3
CS
current sense input
This pin senses the primary current and routes it to
the internal comparator via and L.E.B.
4
Gnd
The IC ground
5
Drv
Driving pulses
The driver's output to an external MOSFET.
6
Vcc
Supplies the IC
This pin is connected to an External bulk capacitor
7 Nc
This unconnected pin ensures adepuate creepage
distance.
8 HV
Ensure a clean and
lossless start-up
sequence
Connected to the high-voltage rail, this pin injects a
constant current into the Vcc capacitor during the
start-up sequence
Summary of Contents for VA2226w-1
Page 5: ...2 ViewSonic Corporation Confidential Do Not Copy VA2226w 1 4 Handling and Placing Methods...
Page 6: ...3 ViewSonic Corporation Confidential Do Not Copy VA2226w 1...
Page 51: ...48 ViewSonic Corporation Confidential Do Not Copy VA2226w 1 Front Cover Back Cover...
Page 52: ...49 ViewSonic Corporation Confidential Do Not Copy VA2226w 1 Keypad Board Chassis...
Page 54: ...51 ViewSonic Corporation Confidential Do Not Copy VA2226w 1 I F Board...
Page 60: ...57 ViewSonic Corporation Confidential Do Not Copy VA2226w 1 6 5 Backlight can t be turned on...
Page 63: ...60 ViewSonic Corporation Confidential Do Not Copy VA2226w 1 6 8 Bad Screen...
Page 64: ...ViewSonic Corporation Confidential Do Not Copy VA2226w 1 7 Block Diagram 61...
Page 70: ...67 ViewSonic Corporation Confidential Do Not Copy VA2226w 1 9 PCB Layout Diagrams...
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