Patent ID: 6922182

Claim:
A display device drive circuit comprising: first transistors, provided in parallel in a plurality for each data line in order to provide to the data lines of a display panel drive currents in accordance with a control potential; second transistors provided for each of said first transistors in order to switch the drive currents for said data lines between a supplied state and a non-supplied state; a potential generating circuit for supplying an identical control potential to said first transistors; and a signal generating circuit that controls a value of the drive currents supplied to said data lines by controlling a number of said second transistors that are in an ON state, said potential generating circuit having a constant current circuit that generates an output potential from a voltage drop when a predetermined current is supplied to a reference resistor, and said constant current circuit comprising a plurality of third transistors provided in parallel in order to supply to said reference resistor an electric current according to the control potential, a plurality of fourth transistors provided for each of said third transistors in order to switch the electric currents provided to said reference resistor between a supplied state and a non-supplied state, and an operational amplifier that outputs, to control terminals of said third transistors, the control potential depending on a difference between the output potential obtained from the voltage drop of said reference resistor and a value of an externally provided voltage signal.