Patent ID: 7375585

Claim:
An amplifier having a wide input common mode voltage range, comprising: (a) first and second differential input transistor pairs, first electrodes of transistors of the first differential input transistor pair being coupled to a first tail current source, first electrodes of transistors of the second differential input transistor pair being coupled to a second tail current source, current flow through one of the first and second tail current sources being controlled by a common mode control circuit in response to an input signal of a differential input signal applied to the amplifier, the input signal including a differential component and a common mode component; (b) an output stage having first and second inputs driven by the second and first differential input transistor pairs, respectively, the output stage producing an output signal representative of the differential component of the input signal; and (c) a first controlled active load circuit connected to second electrodes of one of the first and second differential input transistor pairs and coupled to one of the first and second inputs of the output stage and operable in response to the common mode component of the input signal to divert part of a current through the one of the first and second differential input pairs away from the one of the first and second inputs of the output stage.