Patent ID: 7800447

Claim:
An amplifier comprising: an input stage; an output stage comprising: a first transistor having a first input terminal; and a second transistor having a second input terminal; a monitoring stage comprising: a first current sensing transistor having a third input terminal and a first common terminal, wherein the third input terminal is connected to the first input terminal and the first common terminal is connected to a first voltage rail; and a second current sensing transistor having an fourth input terminal and a second common terminal, wherein the fourth input terminal is connected to the second input terminal and the second common terminal is connected to a second voltage rail; wherein the output stage is a first output stage; wherein the amplifier further comprises a second output stage, the second output stage comprising: a third transistor having a fifth input terminal; a fourth transistor having a sixth input terminal; a voltage monitor; a first switch switchable between at least a first state and a second state, the first switch adapted to connect the fifth input terminal to the first input terminal in the first state, and to disconnect the same in the second state; and a second switch switchable between at least a third state and a fourth state, the second switch adapted to connect the sixth input terminal to the second input terminal in the third state, and to disconnect the same in the fourth state.