ViewSonic VX2262WM - 22" LCD Monitor Service Manual page 23

LD7552DPS (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
1 GND
2 COMP
3 VCC
4 RT
6 NC
7 VCC
8 OUT
ViewSonic Corporation
Ground
Voltage feedback pin (same as the COMP pin in UC384X), By
connecting a photo-coupler to close the control loop and achieve the
regulation
Supply voltage pin
This pin is to program the switching frequency. By connecting a resistor
to ground to set the switching frequency.
Unconnected pin
Supply voltage pin
Gate drive output to drive the external MOSFET
Function
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Confidential - Do Not Cop VX2262wm/wmp