Patent ID: 8149054

Claim:
An operational amplifier comprising: a differential amplifier input stage that supplies an operating current to a differential pair, the differential amplifier input stage comprising a first transistor having a first polarity; a push-pull amplifier output stage that comprises: a second transistor having the first polarity; and a third transistor having a second polarity, the second transistor and the third transistor being connected in series; a capacitive element that connects the gate of the first transistor and a gate of the second transistor, wherein the differential pair is formed by P channel MOS transistors, wherein the first transistor and the second transistor are formed by P channel MOS transistors, wherein the third transistor is formed by an N channel MOS transistor ,and wherein a negative potential is supplied from the gate of the second transistor to the gate of the first transistor when an output signal from the differential amplifier input stage is raised.