Patent ID: 8760169

Claim:
An operational amplifier comprising: an input stage comprising: a first current source operable for generating a first bias current, and a differential input circuit operable for receiving said first bias current and differential input voltage signals, and operable for converting said differential input voltage signals to differential input currents, wherein said input stage is supplied by a first power supply voltage; an output stage comprising: a load circuit coupled to said differential input circuit and operable for receiving said differential input currents and for outputting a single-ended output voltage signal, wherein said output stage is supplied by a second power supply voltage, and wherein said second power supply voltage is lower than said first power supply voltage, wherein the operational amplifier further comprises a control stage operable for receiving a second bias current and an enable signal, and operable for controlling said input stage and said output stage based on said enable signal and for generating a third bias current and a fourth bias current based on said second bias current, wherein said control stage is supplied by said second power supply voltage.