Patent ID: 7173553

Claim:
A D/A converter comprising: a first D/A converter block for converting upper bits of digital data having of a plurality of bits; and a second D/A converter block for converting lower bits of the digital data, said digital data being D/A converted in two steps using said first D/A converter block and said second D/A converter block, wherein said first D/A converter block comprises two or more constant current sources, a first switch for adding respective output currents from a part of said two or more constant current sources, the number of the part corresponds to a value of the upper bits of said digital data, to output an added current, and a second switch for supplying a current from the remaining one constant current source of said two or more constant current sources to said second D/A converter block, wherein said second D/A converter block comprises a current shunt for shunting the current supplied from said first D/A converter block at a shunt ratio corresponding to a value of the lower bits of said digital data and outputting a shunt current, and wherein the current outputted from said first switch and the shunt current outputted from said current shunt are added each other, so that a current corresponding to said digital data is outputted.