Abstract: To prevent the flicker phenomenon on a liquid crystal and the feed through phenomenon in a gate driving unit of a liquid crystal display device,a gate pulse modulate controller is designed.It can minimize power consumption and reduce the coupling effect between gate line and pixel.It applies an output voltage with a time delay to the gate driving unit,thereby preventing erroneous operation of the liquid crystal display device.A current mode PWM Boost DC-DC converter and a charge pump employing this gate pulse modulate controller circuit have been implemented in a UMC 0.6μm-BCD process.The efficiency of the DC-DC converter is up to 93%,the output of the adjustable charge pump is 10～30V,and the results indicate that the circuit works well and effectively.The chip area of the gate pulse modulator circuit is 0.3mm2 and it consumes less than 1μA of quiescent current.

Key words: DC-DC converter, charge pump, gate pulse modulate, adjustable delay time