Gamma regulation and calibration method and apparatus for multi-path driver of display

After an input signal in m digits for analog GAMMA curve is converted to an input signal in n digits, the converted input signal in n digits and another input signal in n digits together are input to a drive unit. The said two input signals being compared, the drive unit outputs a PWM drive signal to specific data channel. Since two groups of input signals for the drive unit are in n digits, thus, the drive unit can be selected from drive units in lower n digits. The invention reduces layout area so as to lower cost further.