Patent ID: 8159207

Claim:
An apparatus comprising: a differential input stage having a first input terminal, a second input terminal, and an output terminal, wherein the first input terminal of the differential input stage receives a reference voltage; an output stage having an input terminal and an output terminal, wherein the output terminal of the output stage is coupled to the second input terminal of the differential input stage; and a gain stage including: a first transistor having a first passive electrode, a second passive electrode, and a control electrode, wherein the first passive electrode of the first transistor is coupled to the output terminal of the output stage, and wherein the control electrode of the first transistor is coupled to the output terminal of the differential input stage, and wherein the second passive electrode is coupled to the input terminal of the output stage; a second transistor having a first passive electrode, a second passive electrode, and a control electrode, wherein the control electrode of the second transistor is coupled to the output terminal of the differential input stage, and wherein the first passive electrode of the second transistor is coupled to the output terminal of the output stage; a current source that is coupled to the output terminal of the output stage; a third transistor having a first passive electrode, a second passive electrode, and a control electrode, wherein the first passive electrode of the third transistor is coupled to the input terminal of the output stage, and wherein the control electrode of the third transistor is coupled to the current source; and a current mirror that is coupled to the second passive electrode of the second transistor and the current source.