Patent ID: 8344978

Claim:
A digital-to-analog converter (DAC) for a display device, the DAC comprising: an amplifier which receives a gradation voltage with respect to upper bits in data of k bits through a non-inverting input terminal, and which varies the input gradation voltage according to a voltage applied to an inverting input terminal; and a current decoder which allows a predetermined constant current to flow therethrough according to input data of lower bits excluding the upper bits to vary the voltage applied to the inverting input terminal, and which adjusts the gradation voltage outputted by the amplifier according to the varied voltage, wherein the current decoder comprises: a feedback resistor which is disposed on a feedback current path from an output terminal of the amplifier to the inverting input terminal of the amplifier; a constant current unit which is connected in series between one terminal of the feedback resistor and a ground terminal, and which undergoes switching according to the input data of the lower bits to flow a predetermined fixed current to the ground terminal, and a buffer switch connected in parallel with the feedback resistor.