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C.
INVERTER
In order to drive the CCFLs embedded in the panel module, there is a half bridge inverter to convert by the
controller.
The input 12V up to hundreds of AC voltage output.
The inverter is formed by symmetric in order to drive the separate lamp modules.
The input stage consists of a PWM controller, half bridge inverter, and switching MOSFET to convert DC input
into AC output.
The output stage consists of a tuning capacitor, coupling capacitor, transformer, push-pull MOSFET pair to boost
AC output up to hundreds of voltage.
And one resister is serial to lamp for output voltage feedback.
There are two signals to control the inverter which come from system.
Logic “high” level which send to I901 is turn on the inverter.
BRI signal control brightness by DC level which was integral from PWM signal.
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VA721