Digital-to-analog converter and method thereof

A digital-to-analog (D/A) converter, for generating a pixel voltage, selectively corresponding to a plurality of levels, in response to a plurality of respective values of a gray level, the D/A converter comprising:

• an operational amplifier, generating the pixel voltage by means of interpolating a first voltage and a second voltage, so as to obtain the pixel voltage ranged between the first and the second voltage;
• and
• a decoder, having values of the gray level segmented into a first value set, corresponding to a substantially non-linear segment of a Gamma curve, and at least a second value set, corresponding to a substantially linear segment of the gamma curve, the decoder comprising:
• a first decode unit, for setting the first voltage and the second voltage to be a same voltage within a first voltage set in responding to a value within the first value set of the gray level, so that the pixel voltage corresponding to the first value set of the gray level is obtained without said generating by means of interpolating of the operational amplifier;
• and
• a second decode unit, for generating a control signal when a least significant bit and a second least significant bit of the gray level are both logical 1 or a third least significant bit of the gray level is logical 1, the second decode unit further for setting the first and the second voltages to be a same first border voltage in response to a maximum value of the at least a second value set of the gray level and the control signal, for setting the first and the second voltages to be a second border voltage in response to a same minimum value of the at least a second value set of the gray level and the control signal, so that the pixel voltage corresponding to the maximum and the minimum values of the at least a second value set of the gray level are obtained without said generating by means of interpolating of the operational amplifier, wherein
• the second decode unit is further for respectively setting the first and the second voltages to be the first and the second border voltages in response to an intermediate value of the at least a second value set of the gray level and the control signal, so that the pixel voltage corresponding to the intermediate value of the at least a second value set of the gray level is obtained by said generating by means of interpolating of the operational amplifier.