ViewSonic VA712-2, Service Manual

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FAN7547A(IC201):
The FAN7547A provides all control functions for a current fed
push-pull self oscillation type converter, and also contains voltage. Typical
operating frequency range is between 30kHz depending on the CCFL(Cold
Cathode Fluorescent Lamp) and the transformer’s characteristics
:
NO. Name Function Description NO. Name Function Description
1 GNDT Ground 8 FB Feedback Input
2 Vds Dimming Voltage Input 9 COMP Error Amplifier Output
3 Vref Reference Voltage 10 S/S Soft Start
4 Vms Dimming Mode Selection 11 OSC Main Ct
5 Rct
Burst Dimming Frequency
Set
12 Vcc Supply Voltage
6 OLP Open Lamp Protection 13 Vcc1 Output Drive Source Voltage
7 SDP Shutdown Protection 14 OUT Output Drive
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VA712-2_ VA712b-2
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