公开(公告)号：US11190168B2

公开(公告)日：2021-11-30

申请号：US16784392

申请日：2020-02-07

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： Jing Bai ,  Tejasvi Das ,  Xin Zhao ,  Lei Zhu ,  Xiaofan Fei

IPC: H03K17/687 ,  H03K3/01 ,  H03K19/0185 ,  H03K19/0175 ,  H04R3/00

Abstract: A driver system may include a first n-type field-effect transistor coupled at its non-gate terminals between an output of the driver system and a first terminal of a supply voltage and configured to drive the output when the first n-type field-effect transistor is activated, a second n-type field-effect transistor coupled at its non-gate terminals between an output of the driver system and a second terminal of the supply voltage and configured to drive the output when the second n-type field-effect transistor is activated, a high-side capacitor coupled to the output of the driver system, and a low-side capacitor coupled to the second terminal of the supply voltage, wherein the high-side capacitor and the low-side capacitor are configured to track and correct for mismatches between a first resistance of the first n-type field-effect transistor and a second resistance of the second n-type field-effect transistor.

公开(公告)号：US11070203B2

公开(公告)日：2021-07-20

申请号：US16162960

申请日：2018-10-17

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： Jing Bai ,  Tejasvi Das ,  Xin Zhao ,  Lei Zhu ,  Xiaofan Fei

IPC: H03K17/687 ,  G06F3/01 ,  H03K17/06 ,  H03K19/0175 ,  H03K19/0185 ,  H03F3/217 ,  H03F3/183 ,  H04R3/12

Abstract: A driver system may include a first n-type field-effect transistor coupled at its non-gate terminals between an output of the driver system and a first terminal of a supply voltage and configured to drive the output when the first n-type field-effect transistor is activated, a second n-type field-effect transistor coupled at its non-gate terminals between an output of the driver system and a second terminal of the supply voltage and configured to drive the output when the second n-type field-effect transistor is activated, a high-side capacitor coupled to the output of the driver system, and a low-side capacitor coupled to the second terminal of the supply voltage, wherein the high-side capacitor and the low-side capacitor are configured to track and correct for mismatches between a first resistance of the first n-type field-effect transistor and a second resistance of the second n-type field-effect transistor.

公开(公告)号：US10009686B1

公开(公告)日：2018-06-26

申请号：US15488931

申请日：2017-04-17

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： Tejasvi Das ,  Xin Zhao ,  John L. Melanson

IPC: H04R3/00 ,  H04R3/04 ,  H03M1/66

CPC classification number: H04R1/1041 ,  H03M1/002 ,  H03M1/742 ,  H04R1/1016 ,  H04R3/00 ,  H04R2460/03

Abstract: A playback path may include an input configured to receive an input signal, an output configured to drive a differential output signal, a differential current-mode digital-to-analog converter configured to convert the input signal into the differential output signal, and a control circuit. The differential current-mode digital-to-analog converter may include a plurality of current-mode digital-to-analog elements configured to be selectively enabled and disabled based on the input signal and at least one reference element in a current mirror relationship with the plurality of current-mode digital-to-analog elements such that each individual current through each current-mode digital-to-analog element is a scaled version of a reference current of the at least one reference element. The control circuit may be configured to scale current mirror ratios between the at least one reference element and the plurality of current-mode digital-to-analog elements based on a characteristic of the input signal.

公开(公告)号：US20180062583A1

公开(公告)日：2018-03-01

申请号：US15418405

申请日：2017-01-27

Applicant: Cirrus Logic International Semiconductor Ltd.

Inventor： Xin Zhao ,  Tejasvi Das ,  Hossein Mirzaie ,  Lei Zhu ,  Xiaofan Fei

IPC: H03F1/26 ,  H03F3/217 ,  H03F3/45 ,  H03F3/183

CPC classification number: H03F1/26 ,  H03F3/187 ,  H03F3/2173 ,  H03F3/45475 ,  H03F3/45928 ,  H03F2200/03 ,  H03F2203/45138 ,  H03F2203/45438 ,  H03F2203/45512

Abstract: A dynamic common reference input (CMRI) signal may be provided to an operational amplifier, or “op-amp,” in an amplifier system to reduce the common mode ripple of the fully-differential op-amp, while adding little or no noise in the amplifier system. The dynamic CMRI signal may be controlled such that a common-mode component of two amplifier input nodes of the operational amplifier is made approximately independent of two input signals received at two system input nodes of the amplifier system. An amplifier system with the dynamic CMRI may be used in class-D amplifiers, such as amplifiers for audio systems that generate output for headphones or speakers.