Patents by Inventor Zhaohui He

Zhaohui He has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20240147068
    Abstract: A control system includes one or more processors and one or more memories. The one or more memories store one or more computer programs that, when executed by the one or more processors, cause the one or more processors to obtain operation information of a movable platform performing an operation in a target area, determine at least one operation abnormal area of the movable platform performing the operation in the target area according to the operation information, determine a corresponding supplement operation path according to the at least one operation abnormal area, and control the movable flatform to perform a supplement operation based on the supplement operation path.
    Type: Application
    Filed: January 9, 2024
    Publication date: May 2, 2024
    Inventors: Zhenhao HUANG, Zhaohui FANG, Gang HE
  • Publication number: 20240110255
    Abstract: The present invention discloses a extra thick hot rolled H section steel and a production method therefor. The extra thick hot rolled H section steel contains, by mass, the following chemical components: 0.04-0.11% of C, 0.10-0.40% of Si, 0.40-1.00% of Mn, 0.40-1.00% of Cr, 0.10-0.40% of Cu, 0.020-0.060% of Nb, 0.040-0.100% of V, 0.010-0.025% of Ti, 0.010-0.030% of Al, 0.0060-0.0120% of N, not more than 0.015% of P, not more than 0.005% of S, not more than 0.0060% of O, and the balance Fe and trace residual elements, wherein 0.090%?Nb+V+Ti?0.170%, 6.5?(V+Ti)/N?10.5, and 0.30%?CEV?0.48%. The extra thick hot rolled H section steel has a flange thickness of 90 mm-150 mm, has excellent comprehensive mechanical properties, and can well meet the needs for heavy supporting structural parts of high-rise buildings, large squares, bridge structures, etc.
    Type: Application
    Filed: October 27, 2021
    Publication date: April 4, 2024
    Inventors: Meng XIA, Baoqiao WU, Meizhuang WU, Jun XING, Jie WANG, Hui CHEN, Jingcheng YAN, Qi HUANG, Lin PENG, Junwei HE, Zhaohui DING, Qiancheng SHEN
  • Publication number: 20230344394
    Abstract: A system may include an analog loop filter comprising a plurality of analog integrators, the analog loop filter configured to receive an analog signal input and a feedback output signal, at least one sampler for sampling outputs of the analog integrators, a second loop filter coupled between an output of an analog pulse-width modulation driver and a digital pulse-width modulation controller, wherein the second loop filter comprises at least one integrator and is configured to receive sampled outputs of the analog integrators from the at least one sampler and receive a feedback pulse-width modulation signal from the analog pulse-width modulation driver, and a correction subsystem configured to apply a non-linear function to a signal path of the second loop filter in order to compensate for non-linearity introduced as a result of sampling outputs of the analog integrators.
    Type: Application
    Filed: April 20, 2023
    Publication date: October 26, 2023
    Applicant: Cirrus Logic International Semiconductor Ltd.
    Inventors: John L. MELANSON, Abhishek MUKHERJEE, Lingli ZHANG, Zhaohui HE
  • Publication number: 20230122151
    Abstract: A method for calibrating a fully-differential input system may include determining a first voltage of a first node of the fully-differential input system, wherein the first node is coupled at the first node to a plurality of first resistors in a first star configuration, determining a second voltage of a second node of the fully-differential input system, wherein the second node is coupled at the second node to a plurality of second resistors in a second star configuration, each resistor of the plurality of second resistors corresponding to a respective resistor of the plurality of first resistors, and trimming individual resistances of the plurality of first resistors and the plurality of second resistors in order to maintain a difference of a first voltage at the first node and a second voltage of the second node at approximately zero.
    Type: Application
    Filed: June 24, 2022
    Publication date: April 20, 2023
    Applicant: Cirrus Logic International Semiconductor Ltd.
    Inventors: Zhaohui HE, Neel PRAMANIK, Lingli ZHANG, Wei XU, Prashanth DRAKSHAPALLI
  • Publication number: 20220376618
    Abstract: This application relates to methods and apparatus for driving a transducer. A transducer driver has a switch network is operable to selectively connect a driver output to any of a first set of at least three different switching voltages. which are, in use, maintained throughout a switching cycle of the driver apparatus. The switch network is also operable to selectively connect the driver output to flying capacitor driver. A controller is configured to control the switch network and flying capacitor driver to generate a drive signal at the driver output based on an input signal, wherein in one mode of operation the driver output is switched between two of the first set of switching voltages with a controlled duty cycle and in another mode of operation the driver output is connected to the flying capacitor driver which is switched between first and second states with a controlled duty cycle.
    Type: Application
    Filed: February 23, 2022
    Publication date: November 24, 2022
    Applicant: Cirrus Logic International Semiconductor Ltd.
    Inventors: Yongjie CHENG, Lingli ZHANG, John L. MELANSON, Thomas H. HOFF, Eric J. KING, Zhaohui HE
  • Patent number: 11290069
    Abstract: A Class-D amplifier that includes a driver stage operable in a plurality of modes having different respective output impedances, a loop filter having an output, and a circuit configured to sense a current at a load of the Class-D amplifier, determine, based on the sensed current, an IR drop for a respective output impedance of the driver stage, and add the IR drop to the loop filter output to compensate for the respective output impedance of the driver stage to reduce distortion.
    Type: Grant
    Filed: August 25, 2020
    Date of Patent: March 29, 2022
    Assignee: Cirrus Logic, Inc.
    Inventors: Zhaohui He, Ruoxin Jiang, Rahul Singh
  • Patent number: 11245370
    Abstract: A Class-D amplifier includes a plurality of power rails, a quantizer, and a driver stage. The quantizer and the driver stage have a combined gain. For each power rail of the plurality of power rails, the Class-D amplifier senses a voltage value for the power rail and determines a ramp amplitude based on the sensed voltage value. The Class-D amplifier concurrently switches from the driver stage using a first power rail to a second power rail of the plurality of power rails and switches from the quantizer using the ramp amplitude associated with the first power rail to using the ramp amplitude associated with the second power rail so that the combined gain is constant.
    Type: Grant
    Filed: August 25, 2020
    Date of Patent: February 8, 2022
    Assignee: Cirrus Logic, Inc.
    Inventors: Zhaohui He, Ruoxin Jiang, Rahul Singh
  • Patent number: 10972061
    Abstract: A Class-D amplifier having a low power dissipation mode includes first and second independent output stages that receive respective first and second level power supply voltages for driving a load coupled to the amplifier output during respective first and second operating modes. Bypass switches are controllable to disconnect the second output stage from the output during the first operating mode and to connect the second output stage to the output during the second operating mode. The operating modes are selected based on the amplifier output power level. First and second independent pre-driver stages receive the respective first and second level power supply voltages for driving the respective first and second independent output stages. During the second operating mode the first pre-driver stage is placed into a low power dissipation state and during the first operating mode the second pre-driver stage is placed into a low power dissipation state.
    Type: Grant
    Filed: November 8, 2018
    Date of Patent: April 6, 2021
    Assignee: Cirrus Logic, Inc.
    Inventors: Zhaohui He, Rahul Singh, Ruoxin Jiang
  • Publication number: 20210044264
    Abstract: A Class-D amplifier includes a plurality of power rails, a quantizer, and a driver stage. The quantizer and the driver stage have a combined gain. For each power rail of the plurality of power rails, the Class-D amplifier senses a voltage value for the power rail and determines a ramp amplitude based on the sensed voltage value. The Class-D amplifier concurrently switches from the driver stage using a first power rail to a second power rail of the plurality of power rails and switches from the quantizer using the ramp amplitude associated with the first power rail to using the ramp amplitude associated with the second power rail so that the combined gain is constant.
    Type: Application
    Filed: August 25, 2020
    Publication date: February 11, 2021
    Inventors: Zhaohui He, Ruoxin Jiang, Rahul Singh
  • Publication number: 20210044265
    Abstract: A Class-D amplifier that includes a driver stage operable in a plurality of modes having different respective output impedances, a loop filter having an output, and a circuit configured to sense a current at a load of the Class-D amplifier, determine, based on the sensed current, an IR drop for a respective output impedance of the driver stage, and add the IR drop to the loop filter output to compensate for the respective output impedance of the driver stage to reduce distortion.
    Type: Application
    Filed: August 25, 2020
    Publication date: February 11, 2021
    Inventors: Zhaohui He, Ruoxin Jiang, Rahul Singh
  • Patent number: 10862442
    Abstract: In a Class-D amplifier, first/second ratios and first/second RC time constants are sequentially matched by trimming. An integrator is coupled to differential first/second paths. The first/second ratios are of a feedback resistor to an input resistor in the first/second paths. R's of the first/second RC time constants are the resistors of the first/second matched ratios. C's of the first/second RC time constants are integrating capacitors in the first/second path. For each of multiple power rails, a ramp amplitude is determined based on a sensed voltage. Concurrently, the driver stage is switched from first to second power rails and quantizer switched from first to second ramp amplitudes to achieve constant combined quantizer/driver stage gain. Based on a sensed load current, an IR drop is determined for a respective output impedance of the driver stage and added to a loop filter output to compensate for the respective output impedance.
    Type: Grant
    Filed: November 8, 2018
    Date of Patent: December 8, 2020
    Assignee: Cirrus Logic, Inc.
    Inventors: Zhaohui He, Rahul Singh, Ruoxin Jiang
  • Patent number: 10476455
    Abstract: A class-D amplifier system includes one or more pulse width modulation (PWM) output paths at least one of which includes one or more digital closed-loop PWM modulators (DCL-PWMM) in which at least one of the DCL_PWMM includes a digital integrator that provides an output value and receives a feedback value. The output value has an output resolution and the feedback value has a feedback resolution that is coarser than the output resolution. The output value is the sum of an integer multiple of the feedback resolution and a residue. Control logic decreases/increases the residue of the digital integrator toward an integer multiple of the feedback resolution over a plurality of clock cycles in response to a request to transition the class-D amplifier and forces an output of the DCL_PWMM to have an approximate 50% duty cycle after decreasing/increasing the residue over the plurality of clock cycles.
    Type: Grant
    Filed: August 8, 2018
    Date of Patent: November 12, 2019
    Assignee: Cirrus Logic, Inc.
    Inventors: Paul Astrachan, Emmanuel Marchais, Lingli Zhang, Zhaohui He, Kyehyung Lee, Tejasvi Das, John L. Melanson
  • Publication number: 20190149107
    Abstract: In a Class-D amplifier, first/second ratios and first/second RC time constants are sequentially matched by trimming. An integrator is coupled to differential first/second paths. The first/second ratios are of a feedback resistor to an input resistor in the first/second paths. R's of the first/second RC time constants are the resistors of the first/second matched ratios. C's of the first/second RC time constants are integrating capacitors in the first/second path. For each of multiple power rails, a ramp amplitude is determined based on a sensed voltage. Concurrently, the driver stage is switched from first to second power rails and quantizer switched from first to second ramp amplitudes to achieve constant combined quantizer/driver stage gain. Based on a sensed load current, an IR drop is determined for a respective output impedance of the driver stage and added to a loop filter output to compensate for the respective output impedance.
    Type: Application
    Filed: November 8, 2018
    Publication date: May 16, 2019
    Inventors: ZHAOHUI HE, RAHUL SINGH, RUOXIN JIANG
  • Publication number: 20190149101
    Abstract: A Class-D amplifier having a low power dissipation mode includes first and second independent output stages that receive respective first and second level power supply voltages for driving a load coupled to the amplifier output during respective first and second operating modes. Bypass switches are controllable to disconnect the second output stage from the output during the first operating mode and to connect the second output stage to the output during the second operating mode. The operating modes are selected based on the amplifier output power level. First and second independent pre-driver stages receive the respective first and second level power supply voltages for driving the respective first and second independent output stages. During the second operating mode the first pre-driver stage is placed into a low power dissipation state and during the first operating mode the second pre-driver stage is placed into a low power dissipation state.
    Type: Application
    Filed: November 8, 2018
    Publication date: May 16, 2019
    Inventors: ZHAOHUI HE, RAHUL SINGH, RUOXIN JIANG
  • Patent number: 10090814
    Abstract: A signal processing system for producing a load voltage at a load output of the signal processing system, wherein the load output comprises a first load terminal having a first load voltage and a second load terminal having a second load voltage such that the load voltage comprises a difference between the first load voltage and the second load voltage, and may include a first processing path configured to process a first signal derived from an input signal to generate the first load voltage at a first processing path output, a second processing path configured to process a second signal received at a second processing path input and derived from the input signal, wherein the second signal comprises information of the input signal absent from the first signal, to generate the second load voltage at a second processing path output, and a high-pass filter coupled between the first processing path output and the second processing path input.
    Type: Grant
    Filed: September 20, 2016
    Date of Patent: October 2, 2018
    Assignee: Cirrus Logic, Inc.
    Inventors: John L. Melanson, Eric J. King, Zhaohui He, Siddharth Maru
  • Patent number: 9985587
    Abstract: A switching power stage for producing a load voltage at a load output of the switching power stage, wherein the load output comprises a first load terminal having a first load voltage and a second load terminal having a second load voltage such that the load voltage comprises a difference between the first and the second load voltages, that may include: a power converter comprising a power inductor and a plurality of switches, wherein the power converter is configured to drive a power converter output terminal; a linear amplifier configured to drive a linear amplifier output terminal; and a controller for controlling the plurality of switches and the linear amplifier in order to generate the load voltage as a function of an input signal to the controller such that energy delivered to the load output is supplied predominantly by the power converter.
    Type: Grant
    Filed: May 31, 2016
    Date of Patent: May 29, 2018
    Assignee: Cirrus Logic, Inc.
    Inventors: Zhaohui He, Eric J. King, Siddharth Maru, John L. Melanson
  • Patent number: 9973156
    Abstract: A method may include processing a first signal derived from an input signal with a first path to generate a first path voltage at a first path output, processing a second signal derived from the input signal with a second path to generate a second path voltage at a second path output, the second path comprising a linear amplifier having at least one transistor for driving the second path voltage, generating the first signal and the second signal with a signal splitter, such that the second signal comprises information of the input signal absent from the first signal, and such that the second path voltage is of a sufficient magnitude such that the at least one transistor operates in a saturation region of the at least one transistor throughout a dynamic range of a load voltage equal to the difference of the first path voltage and the second path voltage.
    Type: Grant
    Filed: October 4, 2016
    Date of Patent: May 15, 2018
    Assignee: Cirrus Logic, Inc.
    Inventors: Eric J. King, Zhaohui He, John L. Melanson, Siddharth Maru
  • Patent number: 9929664
    Abstract: A method may include controlling switches of a switching full-bridge of a signal processing system to commutate polarity of a capacitor with respect to the first processing path output and a second processing path output of the signal processing system in response to a condition for commutating connectivity of the switching full-bridge and inserting a feedforward compensation that bypasses a loop filter of the second processing path in order to prevent discontinuities caused by commutating polarity of the capacitor from being compensated by the loop filter.
    Type: Grant
    Filed: September 30, 2016
    Date of Patent: March 27, 2018
    Assignee: Cirrus Logic, Inc.
    Inventors: Eric J. King, Zhaohui He, Siddharth Maru, John L. Melanson
  • Patent number: 9906196
    Abstract: A switching power stage for producing a load voltage may include a first processing path having a first output, a second processing path having a second output, a first plurality of switches comprising at least a first switch coupled between the first output and a first load terminal and a second switch coupled between the first output and the second load terminal, a second plurality of switches comprising at least a third switch coupled between the second output and the first load terminal and a fourth switch coupled between the second output and the second load terminal, and a controller configured to control switches in order to generate the load voltage as a function of an input signal such that one of the first switch and the second switch operates in a linear region of operation and one of the third switch and the fourth switch operates in a saturated region of operation for a predominance of a dynamic rage of the load voltage.
    Type: Grant
    Filed: September 20, 2016
    Date of Patent: February 27, 2018
    Assignee: Cirrus Logic, Inc.
    Inventors: Zhaohui He, Eric J. King, Siddharth Maru, John L. Melanson
  • Publication number: 20170272044
    Abstract: A signal processing system for producing a load voltage at a load output of the signal processing system, wherein the load output comprises a first load terminal having a first load voltage and a second load terminal having a second load voltage such that the load voltage comprises a difference between the first load voltage and the second load voltage, and may include a first processing path configured to process a first signal derived from an input signal to generate the first load voltage at a first processing path output, a second processing path configured to process a second signal received at a second processing path input and derived from the input signal, wherein the second signal comprises information of the input signal absent from the first signal, to generate the second load voltage at a second processing path output, and a high-pass filter coupled between the first processing path output and the second processing path input.
    Type: Application
    Filed: September 20, 2016
    Publication date: September 21, 2017
    Applicant: Cirrus Logic International Semiconductor Ltd.
    Inventors: John L. MELANSON, Eric J. KING, Zhaohui HE, Siddharth MARU