US Patent 8736373 Output buffer of source driver

An output buffer of a source driver is disclosed. The output buffer includes a buffer input, a buffer output, a differential input stage, a bias current source, an output stage, a compensation capacitor, and a comparator. The output stage and the comparator are both operated between an analog supply voltage (AVDD) and a ground voltage (AGND). The comparator compares an input voltage and an output voltage and outputs a control signal to the bias current source according to the compared result to control a bias current outputted by the bias current source to enhance the slew rate of the output buffer.