Patent Number: 7,714,646

Title: Audio power amplifier and a pre-amplifier thereof

Abstract: An audio power amplifier includes a pre-amplifier, an error amplifier, a comparator, a bridge circuit, and a feedback circuit, in which the gain of the pre-amplifier gradually increases when the audio power amplifier is powered on. The comparator generates a PWM signal by comparing a reference signal and an amplified audio signal. The bridge circuit has switches controlled according to the PWM signal such that a driving current alternately flows to and from a load. The feedback circuit generates the feedback signal indicating a condition of the load.

Inventors: Li; Po-Yu (Fonghua Village, TW), Tseng; Kuan-Jen (Fonghua Village, TW)

Assignee: Himax Analogic, Inc.

International Classification: H03F 3/38 (20060101)

Expiration Date: 5/11/12018