Patent ID: 8766965

Claim:
A drive circuit of a display device comprising a decoder circuit which outputs a tone voltage corresponding to a 8-bit digital value, wherein the decoder circuit comprises: a first decoder circuit and a second decoder circuit which output one voltage respectively using upper-order 6 bits out of the 8-bit digital value; a data selector circuit which outputs a selection signal from 3-bit digital data; a selection circuit which receives two voltages outputted from the first decoder circuit and the second decoder circuit, and distributes the two voltages to three terminals using lower-order 2 bits out of the 8-bit digital value; and an intermediate voltage output circuit which receives three voltages which is applied on the three terminals by the selection circuit, and outputs an intermediate voltage which is a one of five kinds of values based on the three voltages, wherein the first decoder circuit and the second decoder circuit respectively include a select-switch-type decoder circuit which uses lower-order 3 bits out of the upper-order 6 bits, and a tournament-type decoder circuit which uses upper-order 3 bits out of the upper-order 6 bits, the select-switch-type decoder circuit includes switching elements which receive the selection signal outputted from the data selector circuit and switch ON state in response to the selection signal, the tournament-type decoder circuit includes switching elements for every bit, the switching elements of the lower-order bit select one of two values, and output the one of two values selected to the switching elements of upper-order bits, and the data selector circuit is used in common by the first decoder circuit and the second decoder circuit.