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- 19 –
ViewSonic Corporation
Confidential - Do Not Cop
VA1721wmb
Circuit Diagram
LD7552BPS (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
Содержание VA1721wmb - 17" LCD Monitor
Страница 22: ...22 ViewSonic Corporation Confidential Do Not Cop VA1721wmb Block Diagram...
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Страница 37: ...37 ViewSonic Corporation Confidential Do Not Cop VA1721wmb Sep2 Inpute the S N and execute Enter...
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Страница 39: ...39 ViewSonic Corporation Confidential Do Not Cop VA1721wmb Sep3 Key the Enter and write the data...
Страница 40: ...40 ViewSonic Corporation Confidential Do Not Cop VA1721wmb Sep4 If ddc program OK and show data compare ok...
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