Pwm Control Circuit - BenQ Q7T4-FP71G Service Manual

Q7T4-FP71G LCD Monitor Service Guide
Circuit Operation Theory

3.2 PWM Control circuit

TL1451 is a dual PWM controller.C807 and R811 decide the working frequency.BLT_ADJ signal is
from control board, control pulse width then decide how much energy delivery to CCFL also decide
CCFL brightness. Q810 and Q811 be the buffer to rise the drive capability and the totem poles
circuit can improve a capable of driving for Q812.C813 decide the striking time delay.
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