Patents by Inventor Qiming Zhao

Qiming Zhao 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: 20240079478
    Abstract: A preparation method of a gallium oxide device based on high-temperature annealing technology and a gallium oxide device are provided. The preparation method includes: preparing a first barrier layer on a surface of a gallium oxide wafer to block an oxygen atmosphere; implementing a patterning process for regulating impurities of the gallium oxide wafer on the barrier layer, a process depth of the patterning process not exceeding a thickness of the barrier layer; annealing the gallium oxide wafer subjected to above treatment in the oxygen atmosphere; removing the barrier layer; and removing a surface layer of the gallium oxide wafer with the barrier layer lifted off. Problems that a local region of a gallium oxide material cannot be treated alone and net carrier concentration in a selective region of the gallium oxide material cannot be regulated with high-temperature annealing technology in the oxygen atmosphere in related art are solved.
    Type: Application
    Filed: June 29, 2023
    Publication date: March 7, 2024
    Inventors: Guangwei XU, Qiming HE, Xuanze ZHOU, Qiuyan LI, Xiaolong ZHAO, Shibing LONG
  • Publication number: 20230318495
    Abstract: A BLDC motor system having a power stage, a hall sensor and a logical control circuit is discussed. The BLDC motor system improves performances by judging an initial rotation direction through the back electromotive force generated by the stator together with the induced signal sensed by the hall sensor.
    Type: Application
    Filed: April 3, 2023
    Publication date: October 5, 2023
    Inventors: Hongqiang Qin, Yishan Ma, Qiming Zhao, Licheng Sheng
  • Publication number: 20230261594
    Abstract: A driving circuit for a motor has a multiplexer, a current polarity detection circuit, a first comparison circuit, a reverse current control circuit, a first bridge circuit, and a second bridge circuit. The multiplexer chooses a voltage at a common node of two switches of the first bridge circuit or a voltage at a common node of two switches of the second bridge circuit as a chosen common node voltage based on a hall sensing signal. The comparison circuit provides a comparison signal by comparing the chosen common node voltage with an input voltage. The reverse current control circuit determines whether to control a low-side switch of the first bridge circuit or a low-side switch of the second bridge circuit to work in a low-dropout linear regulation (LDO) mode based on the comparison signal and a polarity indication signal provided by the current polarity detection circuit.
    Type: Application
    Filed: December 19, 2022
    Publication date: August 17, 2023
    Inventors: Hongqiang Qin, Qiming Zhao
  • Patent number: 10965236
    Abstract: A motor control system has a computing device and a motor controller. The computing device receives user demands through a GUI, and provides a preset speed table based on the user demands. The preset speed table has a plurality of fixed values of a duty cycle of a pulse width modulation signal and a plurality of preset values of a preset motor speed corresponding to the plurality of fixed values of the duty cycle of the pulse width modulation signal. The motor controller provides the pulse width modulation signal to drive a motor based on the preset speed table.
    Type: Grant
    Filed: August 16, 2019
    Date of Patent: March 30, 2021
    Assignee: Chengdu Monolithic Power Systems Co., Ltd.
    Inventors: Qiming Zhao, Long Li
  • Patent number: 10879706
    Abstract: A battery balancing method and circuit for balancing the voltages between battery units with a fly capacitor. In a first time period of a switching cycle, the first battery unit is used to charge the fly capacitor or the first battery unit is used to discharge the fly capacitor, depending on which of the first battery unit and the fly capacitor having a larger voltage value; and in a second time period of the switching cycle, the second battery unit is used to charge the fly capacitor or the second battery unit is used to discharge the fly capacitor, depending on which of the second battery unit and the fly capacitor having a larger voltage value.
    Type: Grant
    Filed: July 10, 2018
    Date of Patent: December 29, 2020
    Assignee: Chengdu Monolithic Power Systems Co., Ltd.
    Inventors: Rui Wang, Min Xu, Qiming Zhao
  • Publication number: 20200067440
    Abstract: A motor control system has a computing device and a motor controller. The computing device receives user demands through a GUI, and provides a preset speed table based on the user demands. The preset speed table has a plurality of fixed values of a duty cycle of a pulse width modulation signal and a plurality of preset values of a preset motor speed corresponding to the plurality of fixed values of the duty cycle of the pulse width modulation signal. The motor controller provides the pulse width modulation signal to drive a motor based on the preset speed table.
    Type: Application
    Filed: August 16, 2019
    Publication date: February 27, 2020
    Inventors: Qiming Zhao, Long Li
  • Publication number: 20200021118
    Abstract: A battery balancing method and circuit for balancing the voltages between battery units with a fly capacitor.
    Type: Application
    Filed: July 10, 2018
    Publication date: January 16, 2020
    Inventors: Rui Wang, Min Xu, Qiming Zhao
  • Patent number: 10381854
    Abstract: A battery charging system has a switching circuit and a control circuit. The switching circuit has a first switch, and the control circuit has a plurality of analog control loops and a digital control unit. Each of the analog control loops provides a loop control signal based on a corresponding feedback signal, a corresponding reference signal and a slope compensation signal. The digital control unit provides a switching control signal to control the first switch based on the plurality of analog control loops and a time period control signal, and the digital control unit turns ON or turns OFF the first switch automatically in response to one of the plurality of analog control loops.
    Type: Grant
    Filed: January 29, 2016
    Date of Patent: August 13, 2019
    Assignee: Chengdu Monolithic Power Systems co., Ltd.
    Inventors: Min Xu, Qiming Zhao, Xiaoqing Li
  • Patent number: 10348111
    Abstract: A charging circuit adopts a plurality of feedback control circuits, a constant time signal generator and a logic circuit to control the operation of a power switch. The charge circuit needs no oscillator with high frequency, error amplifier with high speed and high accuracy, or compensation circuit with complicated structure, so the system portability is highly improved.
    Type: Grant
    Filed: January 29, 2016
    Date of Patent: July 9, 2019
    Assignee: Monolithic Power Systems, Inc.
    Inventors: Min Xu, Xiaoqing Li, Qiming Zhao
  • Patent number: 10116155
    Abstract: A battery charging circuit has a first switching circuit and a second switching circuit which are coupled in parallel. A control circuit has a plurality of feedback control loops, a logic integrated circuit, a first logic circuit and a second logic circuit, wherein the plurality of feedback control loops provides a plurality of feedback control signals, the logic integrated circuit provides a logic integrated signal based on the plurality of feedback control signals, the frequency dividing circuit provides a first frequency dividing signal and a second frequency dividing signal based on the logic integrated signal, the first logic circuit controls the first switching circuit based on the first frequency dividing signal and a first duration signal, the second logic circuit controls the second switching circuit based on the second frequency dividing signal and a second duration signal.
    Type: Grant
    Filed: December 21, 2016
    Date of Patent: October 30, 2018
    Assignee: Chengdu Monolithic Power Systems Co., Ltd.
    Inventors: Min Xu, Qiming Zhao
  • Patent number: 10063078
    Abstract: A battery charging circuit has a first switching circuit and a second switching circuit coupled in parallel between an input port and a node, a first switch coupled between the node and a system ground, a second switch coupled between the node and an output port, and a control circuit. When an input voltage is higher than a system voltage, the control circuit controls the first switching circuit and the second switching circuit turned ON and OFF with interleaving, the first switch maintains OFF and the second switch maintains ON. When the input voltage is lower than the system voltage, the control circuit controls the first switch and the second switch turned ON and OFF, and at least one of the first switching circuit and the second switching circuit maintains ON.
    Type: Grant
    Filed: December 21, 2016
    Date of Patent: August 28, 2018
    Assignee: Chengdu Monolithic Power Systems Co., Ltd.
    Inventors: Min Xu, Qiming Zhao
  • Patent number: 9977088
    Abstract: A battery fuel gauge current sensing circuit includes: a sense unit coupled in series with the battery and configured to sense the battery current; a control unit configured to adjust the ON resistance of the sense unit based on the comparison of the voltage across the sense unit and a threshold voltage until the voltage across the sense unit is greater than the threshold voltage; and a sample unit coupled across the sense unit and configured to sample the voltage across the sense unit and to provide an analog sample voltage when the voltage across the sense unit is greater than the threshold voltage.
    Type: Grant
    Filed: February 25, 2016
    Date of Patent: May 22, 2018
    Assignee: Hangzhou MPS Semiconductor Technology Ltd.
    Inventors: Qiming Zhao, Xiaoli Kong
  • Patent number: 9936548
    Abstract: A LED driver adopts one power stage to provide a constant drive current to drive a load, and to provide different power supply voltages to power a smart module according to a dimming signal input by users through the smart module. The LED driver provides high performance with simple circuit structure.
    Type: Grant
    Filed: June 21, 2017
    Date of Patent: April 3, 2018
    Assignee: Chengdu Monolithic Power Systems Co., Ltd.
    Inventors: Naixing Kuang, Kai Wang, Qiming Zhao
  • Publication number: 20180007754
    Abstract: A LED driver adopts one power stage to provide a constant drive current to drive a load, and to provide different power supply voltages to power a smart module according to a dimming signal input by users through the smart module. The LED driver provides high performance with simple circuit structure.
    Type: Application
    Filed: June 21, 2017
    Publication date: January 4, 2018
    Inventors: Naixing Kuang, Kai Wang, Qiming Zhao
  • Patent number: 9812950
    Abstract: A digital PFC circuit with improved power factor is described. The digital PFC circuit uses a compensation current generating unit and a reference current adjust unit to eliminate the effect of a current flowing through an input capacitor to the input current, so that the input current and the input line voltage of the digital PFC circuit are controlled to be in-phase.
    Type: Grant
    Filed: June 11, 2015
    Date of Patent: November 7, 2017
    Assignee: Chengdu Monolithic Power Systems Co., Ltd.
    Inventors: Wenbin Lu, Sicong Lin, Qiming Zhao, Lijie Jiang, Guangchao Zhang
  • Patent number: 9711975
    Abstract: A power bank circuit controlling power switches to operate at different modes in accordance with different external coupling situations is discussed. The power bank circuit may be coupled to either a power source, a digital device, or a plurality of series coupled batteries at a high voltage port; and may be coupled to either a power source, a digital device, or a single battery at a low voltage port.
    Type: Grant
    Filed: January 9, 2015
    Date of Patent: July 18, 2017
    Assignee: Chengdu Monolithic Power Systems Co., Ltd.
    Inventors: Min Xu, Qiming Zhao
  • Publication number: 20170187214
    Abstract: A battery charging circuit has a first switching circuit and a second switching circuit coupled in parallel between an input port and a node, a first switch coupled between the node and a system ground, a second switch coupled between the node and an output port, and a control circuit. When an input voltage is higher than a system voltage, the control circuit controls the first switching circuit and the second switching circuit turned ON and OFF with interleaving, the first switch maintains OFF and the second switch maintains ON. When the input voltage is lower than the system voltage, the control circuit controls the first switch and the second switch turned ON and OFF, and at least one of the first switching circuit and the second switching circuit maintains ON.
    Type: Application
    Filed: December 21, 2016
    Publication date: June 29, 2017
    Inventors: Min Xu, Qiming Zhao
  • Publication number: 20170187213
    Abstract: A battery charging circuit has a first switching circuit and a second switching circuit which are coupled in parallel. A control circuit has a plurality of feedback control loops, a logic integrated circuit, a first logic circuit and a second logic circuit, wherein the plurality of feedback control loops provides a plurality of feedback control signals, the logic integrated circuit provides a logic integrated signal based on the plurality of feedback control signals, the frequency dividing circuit provides a first frequency dividing signal and a second frequency dividing signal based on the logic integrated signal, the first logic circuit controls the first switching circuit based on the first frequency dividing signal and a first duration signal, the second logic circuit controls the second switching circuit based on the second frequency dividing signal and a second duration signal.
    Type: Application
    Filed: December 21, 2016
    Publication date: June 29, 2017
    Inventors: Min Xu, Qiming Zhao
  • Patent number: 9685876
    Abstract: A method of capacitive mode detection is used in a resonant converter. The resonant converter has a square wave generator having a first switch and a second switch, a resonant network, an isolated transformer having a primary winding and a second winding, and a rectifier network providing an output DC voltage for a load. The method of capacitive mode detection includes: detecting a voltage of the secondary winding and generating a voltage detection signal; detecting an output DC voltage of the rectifier network and generating a voltage detecting threshold; comparing the voltage detection signal with the voltage detection threshold when either of the first and the second switches is turned OFF; generating a flag signal indicating whether the resonant converter enters into a capacitive mode based on the comparison result.
    Type: Grant
    Filed: December 18, 2015
    Date of Patent: June 20, 2017
    Assignee: Hangzhou MPS Semiconductor Technology Ltd.
    Inventors: Bairen Liu, Licheng Sheng, Bo Yu, Hongqiang Qin, Qiming Zhao, Naixing Kuang, Eric Yang
  • Patent number: 9661700
    Abstract: A primary control LED driver includes: a switching converter having a main switch and a first winding, and configured to provide an LED driving current; a second winding magnetically coupled to the first winding and configured to provide a power supply voltage at a first terminal; a first sensing resistor with a first terminal coupled to the main switch; a second sensing resistor with a first terminal coupled to the second terminals of the first sensing resistor and the second winding; an output current calculator calculating an equivalent value of the LED driving current based on the voltage at the first terminal of the first sensing resistor; an error amplifier configured to generate a compensation signal based on the equivalent value and a reference voltage; and a control circuit generating a control signal to control the main switch based on the compensation signal.
    Type: Grant
    Filed: November 10, 2015
    Date of Patent: May 23, 2017
    Assignee: Hangzhou MPS Semiconductor Technology Ltd.
    Inventors: Naixing Kuang, Qiming Zhao