Patent ID: 7391262

Claim:
Amplifier circuitry including an input stage comprising: (a) a transconductance stage including first and second input transistors each having a source, a drain, a gate, and a bulk electrode, and a first tail current source coupled to the sources of the first and second input transistors, the gates of the first and second input transistors being coupled to first and second input voltage signals, respectively; (b) a bulk electrode capacitance driver circuit including third and fourth input transistors and first and second cascode transistors each having a source, a drain, a gate, and a bulk electrode, and a second tail current source coupled to the sources and bulk electrodes of the third and fourth input transistors and also to the bulk electrodes of the first and second input transistors, the gates of the third and fourth input transistors being coupled to the first and second input voltage signals, respectively, the gates of the first and second cascode transistors being cross-coupled to the second and first input voltage signals, respectively, the source and drain of the first cascode transistor being coupled to the drain of the third input transistor and a reference voltage conductor, respectively, the source and drain of the second cascode transistor being coupled to the drain of the fourth input transistor and the reference voltage conductor, respectively; and (c) a first output conductor coupled to the drain of the first input transistor and a second output conductor coupled to the drain of the second input transistor.