Diamond View DV172, Руководство по обслуживанию

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DV172 LCD Monitor Service Guide
Circuit Operation Theory
12
3.3) Oscillator Circuit
Royer circuit uses the characteristic of transformer saturation to oscillate. When the DC power inject,
Q759 or Q760 will turns on, and the current Ic increases. After a period, the transistor will leave the
saturation status and Vce increase. The result causes the voltage of primary coil get lower. Finally the
transistor turn off, and another transistor turn on. These statuses are repeated and the pin7 and pin8 of
T751 will get a Sin Wave to turn on CCFL.
C.) Control board introduction:
The main parts of the control board are a push button, and a led.
(a) Push button: It’s a simple switch function, pressing it for “ON” to do the auto adjustment
function, releasing it for “OFF” to do nothing.
(b) Led: It indicates the DPMS status of this LCD monitor; green light means DPMS on (Normal
operating condition). Amber light means DPMS off (Power off condition).