Patent ID: 6529079
Filing Date: 2003-03-04
Classification: H03F

Abstract:
An amplifier circuit comprising:an amplifier transistor having a base terminal connected to receive an input signal, the amplifier transistor being operable to amplify the input signal to generate an output signal; a reference voltage source operable to generate a reference voltage at a reference voltage output node; and a local bias circuit operable to provide a bias voltage to the base terminal of the amplifier transistor, the local bias circuit having: a first transistor having an emitter terminal coupled to the reference voltage output node, the first transistor having a collector terminal coupled to a supply voltage node, the first transistor having a base terminal connected to the collector terminal of the first transistor; a second transistor having a base terminal coupled to the base terminal of the first transistor, the second transistor having a collector terminal coupled to the supply voltage node, the second transistor having an emitter terminal coupled to the base terminal of the amplifier transistor; and a resistor having a first terminal connected to the reference voltage output node, the resistor having a second terminal connected to the emitter terminal of the first transistor.