Patent ID: 8610695

Claim:
A drive circuit for a light emitting display apparatus comprising: a pixel circuit having a light emitting device for emitting a light and a drive transistor for supplying current to the light emitting device; and a threshold value correction circuit having an inversion amplifier for converting an input signal depending on a threshold voltage of the drive transistor into an output signal inversely depending on the threshold voltage of the drive transistor with a gain of unity, wherein the pixel circuit includes switch means for connecting a gate terminal of the driving transistor to a source of a data voltage and a capacitor alternately and for connecting a source terminal of the drive transistor to a constant current source circuit and a ground alternately, wherein the input signal is supplied from a source terminal of the drive transistor and the output signal of the inversion amplifier is stored in the capacitor during a first period in which the gate terminal of the drive transistor is connected to the source of the data voltage, the constant current source circuit is connected to the source terminal of the drive transistor and a constant current supplied from the constant current source circuit flows through the drive transistor, and wherein a current determined by the input signal is supplied from the drive transistor to the light emitting device during a second period in which the gate terminal of the drive transistor is connected to the capacitor and the source terminal of the drive transistor is connected to the ground.