Patent ID: 7847634

Claim:
An amplifier to provide an error current in response to a feedback current, the amplifier comprising: a reference generator arranged to generate a bias current in first and second reference transistors; a first amplifier transistor coupled to generate a reference current in response to a control terminal of said first reference transistor; a second amplifier transistor coupled through second control terminals to said second reference transistor, coupled through current terminals to said first amplifier transistor to define an output node, and having a second current terminal to receive said feedback current; and a third amplifier transistor to provide said error current in response to an error signal at said output node; wherein said reference generator includes: a reference resistor; a differential amplifier having a first input port coupled to said reference resistor and a second input port to receive a reference voltage; and a current transistor coupled through control terminals with said first reference transistor and coupled to drive a current through said reference resistor in response to a signal at an output port of said amplifier.