公开(公告)号：US20220158597A1

公开(公告)日：2022-05-19

申请号：US17667234

申请日：2022-02-08

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： Ramin ZANBAGHI ,  Cory J. PETERSON ,  Eric KIMBALL

IPC: H03F3/217 ,  G01R1/20 ,  G01R19/00 ,  H03K4/06 ,  H03K7/08

Abstract: A system may include a Class-D stage comprising a first high-side switch coupled between a supply voltage and a first output terminal of the Class-D stage, a second high-side switch coupled between the supply voltage and a second output terminal of the Class-D stage, a first low-side switch coupled between a ground voltage and the first output terminal, and a second low-side switch coupled between the ground voltage and the second output terminal. The system may also include current sensing circuitry comprising a sense resistor, such that an output current through a load coupled between the first output terminal and the second output terminal causes a first sense voltage proportional to the output current across the sense resistor. The system may additionally include a modulator for generating a differential pulse-width modulation driving signal to the first high-side switch, the second high-side switch, the first low-side switch, and the second low-side switch and pilot tone injection circuitry configured to inject a periodic pilot tone into the differential pulse-width modulation driving signal at a pilot tone frequency.

公开(公告)号：US20210211099A1

公开(公告)日：2021-07-08

申请号：US16732993

申请日：2020-01-02

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： Eric KIMBALL ,  Chandra PRAKASH ,  Ramin ZANBAGHI ,  Cory J. PETERSON

IPC: H03F1/26 ,  H03F3/217 ,  H03F3/183

Abstract: A system may include a forward signal path having a forward gain and configured to receive an input signal at an input and generate an output signal at an output as a function of the input signal, a feedback signal path having a feedback gain and coupled between the output and the input, and a control subsystem configured to operate the forward signal path and the feedback signal path in at least two modes comprising a first mode in which the forward gain is a first forward gain and the feedback gain is a first feedback gain and a second mode in which the forward gain is a second forward gain smaller than the first forward gain and the feedback gain is a second feedback gain larger than the first feedback gain. The control subsystem may cause operation in the first mode when signal content is present in the input signal and may cause operation in the second mode when signal content is absent from the input signal.