Patent ID: 7161517

Claim:
An M-bit digital-to-analog converter (DAC) for a source driver of a flat display, arranged to convert an M-bit input word into an analog output signal, the M-bit DAC comprising: at least two DAC portions corresponding to two segments of a gamma curve of the flat display, wherein each of the DAC portions comprises: an N-bit R-string DAC section, comprising: a plurality of resistors electrically connected in series to provide a plurality of grayscale voltages; and a 2-of-N selector, coupled to the series-connected resistors, and arranged to select two neighboring grayscale voltages according to an N-bit MSB subword of the M-bit input word; and an (M-N)-bit interpolation DAC section, coupled to the N-bit R-string DAC section, and arranged to interpolate the analog output signal from the two neighboring grayscale voltages according to the (M-N)-bit LSB subword of the M-bit input word; wherein the numbers of bits (Ns) processed by the N-bit R-string DAC sections of the two DAC portions are different.