Patent ID: 7482876

Claim:
An amplifier circuit, comprising a first series circuit connected between a supply voltage connection and a reference potential connection, wherein the first series circuit comprises: a current source; a first tap connected between the current source and the reference potential connection; a first component configured as a diode and a first impedance which are connected in series between the first tap and the reference potential connection; a second series circuit connected between the supply voltage connection and the reference potential connection, and configured to mirror a first current which flows in the first series circuit with scaling to form a second current, wherein the second series circuit comprises: a controlled path between a first connection and a second connection of a first transistor whose control connection is coupled to the first tap; and a second impedance connected between the controlled path of the first transistor and the reference potential connection, having a first connection connected to the controlled path of the first transistor and a second connection connected to a second tap at which a bias voltage is tapped off, a ratio between the second current flowing in the second series circuit and the first current depends on the first and second impedances; an amplifier stage coupled to the second tap, wherein the bias voltage thereat sets an operating point of the amplifier stage.