A High-performance LCD Driver Analog Circuit Based on Charge Pump

Aiming at the problem of unstable liquid crystal output caused by unstable traditional power supply voltage, an LCD driver circuit with high-performance charge pump is designed. Compared to a conventional charge pump circuit, the proposed charge pump circuit output voltage has no threshold voltage loss, and solves the problem of switch leakage by introducing a two-phase non-overlapping clock without increasing the circuit area. We realize a stable output voltage by adding an appropriate negative feedback module. A simulation with typical frequency of 24.0MHz is carry out in HHGrace 110nm CMOS process library and the measured output voltage of charge pump variation is ±0.02V for temperature changes from -40°C to 125°C with different process. The simulation results show that the charge pump output voltage does not change with the power supply voltage, and the output voltage of LCD has good accuracy at different temperature with different process corner, and does not change with the power supply voltage.