公开(公告)号：US20210075404A1

公开(公告)日：2021-03-11

申请号：US17086728

申请日：2020-11-02

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： Gary ROBERTSON ,  Hamed SADATI ,  Rupesh KHARE ,  Sameer BAVEJA

IPC: H03K3/012 ,  H04R3/00 ,  H03K5/08

Abstract: This application relates to methods and apparatus for voltage control, and in particular to maintain safe voltages for components of audio driving circuits that are operable in a high voltage mode. An audio driving circuit (100) may include a power supply module (106) and may be operable such that, in use, a voltage magnitude at a source terminal of at least a first transistor (306, 309, 603, 605) of the audio driving circuit can exceed its gate-source voltage tolerance. A voltage generator (111 P) is configured to output a first intermediate voltage (VSAFEP) to an intermediate voltage path for use as a gate control voltage for at least the first transistor, to maintain its gate-source voltage below tolerance. An intermediate path voltage clamp (114P) is provided for selectively clamping the intermediate voltage path to a voltage level, so as to maintain the magnitude of the gate-source voltage of the first transistor below tolerance. The voltage clamp (114P) is enabled by a reset condition (RST) for the audio driving circuit.