Inverter; Circuit Diagram; Inverter Basic Function - NEC MultiSync LCD1550ME Service Manual

10. Inverter

10.1 Circuit Diagram

Input Power
ON/OFF
circuit

10.2 Inverter basic function

This is a Dc-AC Inverter which is developed for driving 2 Cold Cathode Fluorescent Lamp (CCFL) in LCD
panel backlight system.
Circuit explain below:
(1) On/Off circuit
This is an input signal to turn on or off the AC output voltage of the Inverter.
ON states : On/Off pin>=2.5V
OFF state : On/Off pin<=2.0V
(2) IC (LM393)
It will get input signal from customer system and control the lamps current and brightness. The other
function include burst mode control, PWM control, and soft start.
Buck
circuit
IC
HV
circuit
Royer
circuit Balance
circuit
Protection
circuit
Feedback
circuit
7-9
Lanp:1 Lanp:2