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Circuit Diagram
LD7552BS (IC901):
PWM control, high-voltage startup current. The circuit unit has
functions such as over-current protection, over-voltage protection, output short-circuit
protection and etc. The function of each pin and the inside circuit diagram are as
follows
:
Pin
Name
Function
1 GND Ground
2 COMP
Voltage feedback pin (same as the COMP pin in UC384X), By
connecting a photo-coupler to close the control loop and achieve the
regulation
3
VCC Supply voltage pin
4 RT
This pin is to program the switching frequency. By connecting a resistor
to ground to set the switching frequency.
6 NC
Unconnected
pin
7
VCC Supply voltage pin
8
OUT Gate drive output to drive the external MOSFET
ViewSonic Corporation
Confidential - Do Not Copy
VA712-2_ VA712b-2
23
Содержание VA712-2
Страница 11: ...ViewSonic Corporation Confidential Do Not Copy VA712 2_ VA712b 2 8 3 Front Panel Function Control Description...
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Страница 43: ...Sep2 Inpute the S N and execute Enter ViewSonic Corporation Confidential Do Not Copy VA712 2_ VA712b 2 40...
Страница 44: ...ViewSonic Corporation Confidential Do Not Copy VA712 2_ VA712b 2 41...
Страница 45: ...Sep3 Key the Enter and write the data ViewSonic Corporation Confidential Do Not Copy VA712 2_ VA712b 2 42...
Страница 50: ...ViewSonic Corporation Confidential Do Not Copy VA712 2_ VA712b 2 47 Picture 13 Picture 14 Picture 15...
Страница 52: ...ViewSonic Corporation Confidential Do Not Copy VA712 2_ VA712b 2 49 6 Troubleshooting Flow Chart...
Страница 59: ...8 Exploded Diagram and Exploded Parts List ViewSonic Corporation Confidential Do Not Copy VA712 2_ VA712b 2 56...
Страница 63: ...ViewSonic Corporation Confidential Do Not Copy VA712 2_ VA712b 2 60 9 Block Diagram...
Страница 74: ...ViewSonic Corporation Confidential Do Not Copy VA712 2_ VA712b 2 71 11 5 POWER PCB TOP VIEW...
Страница 75: ...ViewSonic Corporation Confidential Do Not Copy VA712 2_ VA712b 2 72 11 6 POWER PCB BUTTON VIEW...
Страница 76: ...ViewSonic Corporation Confidential Do Not Copy VA712 2_ VA712b 2 73 11 7 AUDIO PCB TOP VIEW BUTTON VIEW...