Patent ID: 7649417
Filing Date: 2010-01-19
Classification: H03F

Abstract:
1. A circuit for audio amplification, comprising: an input differential pair including a first bipolar transistor having at least a base, a collector, and an emitter; and a second bipolar transistor having at least a base, a collector, and an emitter; a bias current duplicator transistor having at least a base, a collector, and an emitter; a plurality of translinear elements that are arranged such that a voltage between the collector and the emitter of the bias current duplicator transistor is substantially the same as a voltage between the collector and the emitter of the first bipolar transistor; and a current mirror having at least an input that is coupled to the base of the bias current duplicator transistor, a first output that is coupled to the base of the first bipolar transistor, and a second output that is coupled to the base of the second bipolar transistor, wherein the plurality of translinear elements include: