公开(公告)号：EP3661053A1

公开(公告)日：2020-06-03

申请号：EP19211832.1

申请日：2019-11-27

Applicant: STMicroelectronics (Shenzhen) R&D Co., Ltd.

Inventor： LI, Xiang Sheng ,  DU, Ru Feng

IPC: H03F1/30 ,  H03F1/02 ,  H03F3/30 ,  H03F3/68

Abstract: An audio amplifier (400) includes: a buck controller (406, 408) configured to control an output voltage at a first supply terminal, the output voltage selected from a set including a plurality of output voltages, where the output voltage takes a settling time to settle; a first audio bridge including: a class-AB driver stage coupled to the first supply terminal, and a delay insertion circuit configured to receive a processed digital stream and provide the processed digital stream to the class-AB driver stage a delay time after receiving the processed digital stream, where the delay time is based on the settling time; and an audio amplitude detector configured to detect a first peak amplitude in the first digital audio stream, where the buck controller (406, 408) is configured to select a lowest output voltage from the set that is higher than the first peak amplitude plus a headroom voltage.