An output buffer with slew-rate calibration for different TFT-LCD loadings

摘要

An output buffer with slew-rate calibration for different TFT-LCD loadings is presented. Unlike other output buffers of column drivers, the proposed output buffer adjusts the output current according to the loading capacitors. The settling time and slew-rate of the proposed output buffer are thus fixed in an acceptable range for different TFT-LCD loading capacitors, allowing more accurate color quality. The proposed output buffer amplifier is implemented on standard 0.35µm CMOS 2-poly 4-metal process technology and simulated using HSPICE. The settling time of rising and falling for 10kΩ+50pF∼10kΩ+600pF are 0.45µs∼1.40µs and 0.75µs ∼1.84µs, respectively.