Patents by Inventor Zhao-Jun Wang

Zhao-Jun Wang 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: 20210351685
    Abstract: A controller comprising a regulation circuit and a frequency request circuit. The regulation circuit configured to receive a signal representative of an output and a reference representative of a desired value of the output, the regulation circuit configured to output a regulation signal in response to a difference between the signal and the reference. The frequency request circuit configured to receive the regulation signal and outputs an increment signal representative of a request to increase a switching frequency and a decrement signal representative of a request to decrease the switching frequency in response to the regulation signal. The frequency request circuit configured to assert the increment signal when the output is less than the desired value for a duration longer than a first period and assert the decrement signal when the output is greater than the desired value for a duration longer than a second period.
    Type: Application
    Filed: May 11, 2020
    Publication date: November 11, 2021
    Applicant: Power Integrations, Inc.
    Inventors: Sundaresan Sundararaj, Zhao-Jun Wang, Tiziano Pastore, Lance M. Wong
  • Publication number: 20210328516
    Abstract: A control circuit comprising an output controller coupled to an output side of a power converter. The output controller comprises a switch control signal generator to receive a feedback signal representative of an output of the power controller and to communicate a control signal to an input controller coupled to an input side to control a turn ON of a power switch. The control signal is generated in response to the feedback signal and is communicated in response to an enable signal. The output controller comprises an extremum locator to generate the enable signal in response to a winding signal representative of an instantaneous voltage on an output terminal of an energy transfer element and the extremum locator enables the switch control signal generator such that the transition of the power switch from the OFF state to the ON state occurs substantially when the winding signal reaches an extremum.
    Type: Application
    Filed: June 30, 2021
    Publication date: October 21, 2021
    Applicant: POWER INTEGRATIONS, INC.
    Inventors: BALU BALAKRISHNAN, DAVID MICHAEL HUGH MATTHEWS, VIKRAM BALAKRISHNAN, ROLAND SYLVERE SAINT-PIERRE, ZHAO-JUN WANG, GIAO MINH PHAM, QING MCINTOSH
  • Patent number: 11115411
    Abstract: A method of setting up a cloud cluster is disclosed as providing at least one compute node with a baseboard management controller (BMC), the BMC of the compute node receiving secured information and using the secured information to establish communication with a cloud controller. Upon establishing the communication, the compute node then receives a cloud operating system (OS) image from the cloud controller via the BMC of the compute node. Finally, the cloud OS image is written to a host system in the compute node. A compute node is also disclosed.
    Type: Grant
    Filed: September 11, 2019
    Date of Patent: September 7, 2021
    Assignee: Lenovo Enterprise Solutions (Singapore) Pte. Ltd.
    Inventors: Xiaole Shang, Zhao Li Wang, Li Jun Gu
  • Patent number: 11095263
    Abstract: A signal amplifier for use in a power converter includes a variable reference generator coupled to generate a reference signal in response to a dimming control signal. A variable gain circuit is coupled to receive the reference signal, the gain signal, and a feedback signal representative of an output of the power converter. The variable gain circuit is coupled to output a first adjusted signal in response to the reference signal and the gain signal. The variable gain circuit is coupled to output a second adjusted signal in response to the feedback signal and the gain signal. An auxiliary amplifier is coupled to output the gain signal in response to the first adjusted signal and a set signal.
    Type: Grant
    Filed: January 30, 2018
    Date of Patent: August 17, 2021
    Assignee: POWER INTEGRATIONS, INC.
    Inventors: Lance M. Wong, Qing McIntosh, Zhao-Jun Wang
  • Patent number: 11081964
    Abstract: A method of providing an input switching request signal to an input side switch includes determining a switching request window indicative of relaxation ringing during a first switching cycle. It is determined that the input side switch is operating in a discontinuous conduction mode (DCM) mode of operation during a second switching cycle. It is determined that the switching request window is open during the second switching cycle. The input switching request signal is enabled in response to determining the switching request window is open.
    Type: Grant
    Filed: October 9, 2018
    Date of Patent: August 3, 2021
    Assignee: Power Integrations, Inc.
    Inventors: Balu Balakrishnan, David Michael Hugh Matthews, Vikram Balakrishnan, Roland Sylvere Saint-Pierre, Zhao-Jun Wang, Giao Minh Pham, Qing McIntosh
  • Publication number: 20200358413
    Abstract: A signal amplifier for use in a power converter includes a variable reference generator coupled to generate a reference signal in response to a dimming control signal. A variable gain circuit is coupled to receive the reference signal, the gain signal, and a feedback signal representative of an output of the power converter. The variable gain circuit is coupled to output a first adjusted signal in response to the reference signal and the gain signal. The variable gain circuit is coupled to output a second adjusted signal in response to the feedback signal and the gain signal. An auxiliary amplifier is coupled to output the gain signal in response to the first adjusted signal and a set signal.
    Type: Application
    Filed: January 30, 2018
    Publication date: November 12, 2020
    Applicant: Power Integrations, Inc.
    Inventors: Lance M. Wong, Qing Mclntosh, Zhao-Jun Wang
  • Patent number: 10826375
    Abstract: A controller for use in a power converter comprising a request control circuit coupled to receive a feedback signal representative of an output of the power converter. The request control circuit is coupled to generate a request signal for controlling a power switch. The request signal can include a synchronization signal in response to the feedback signal and a jitter average signal. The synchronization signal is generated by the request transmitter circuit and corresponds to an average on time for controlling the power switch.
    Type: Grant
    Filed: December 11, 2018
    Date of Patent: November 3, 2020
    Assignee: Power Integrations, Inc.
    Inventors: Zhao-Jun Wang, Sundaresan Sundararaj, Tiziano Pastore, Qing McIntosh, Lance M. Wong
  • Patent number: 10826398
    Abstract: Apparatus and methods for sensing a variable amplitude switching signal from a secondary winding in a power conversion system are disclosed herein. By using a comparator with an adaptable reference, variable amplitude secondary winding signals in phase with primary winding signals may be detected in the presence of ringing. Detection of the in phase secondary winding signals, in turn, allows for secondary side control with power factor correction and discontinuous mode operation.
    Type: Grant
    Filed: December 12, 2018
    Date of Patent: November 3, 2020
    Assignee: Power Integrations, Inc.
    Inventors: Zhao-Jun Wang, Qing McIntosh
  • Publication number: 20200195163
    Abstract: Apparatus and methods for sensing a variable amplitude switching signal from a secondary winding in a power conversion system are disclosed herein. By using a comparator with an adaptable reference, variable amplitude secondary winding signals in phase with primary winding signals may be detected in the presence of ringing. Detection of the in phase secondary winding signals, in turn, allows for secondary side control with power factor correction and discontinuous mode operation.
    Type: Application
    Filed: December 12, 2018
    Publication date: June 18, 2020
    Applicant: Power Integrations, Inc.
    Inventors: Zhao-Jun Wang, Qing McIntosh
  • Publication number: 20200186021
    Abstract: A controller for use in a power converter comprising a request control circuit coupled to receive a feedback signal representative of an output of the power converter. The request control circuit is coupled to generate a request signal for controlling a power switch. The request signal can include a synchronization signal in response to the feedback signal and a jitter average signal. The synchronization signal is generated by the request transmitter circuit and corresponds to an average on time for controlling the power switch.
    Type: Application
    Filed: December 11, 2018
    Publication date: June 11, 2020
    Applicant: Power Integrations, Inc.
    Inventors: Zhao-Jun Wang, Sundaresan Sundararaj, Tiziano Pastore, Qing McIntosh, Lance M. Wong
  • Patent number: 10644688
    Abstract: A driver circuit for use in a controller includes a signal generator coupled to generate a first control signal and a second control signal in response to a drive signal that is coupled to control switching of a secondary switch that is to be coupled to the driver circuit and referenced to a reference voltage that is greater than a ground reference voltage. A second switch is coupled to be controlled by the second control signal such that the reference voltage is substantially applied to a control of the secondary switch when the drive signal controls the secondary switch to be off. A first switch is coupled to be controlled by the first control signal such that the sum of the reference voltage and a first voltage is substantially applied to the control of the secondary switch when the drive signal controls the secondary switch on.
    Type: Grant
    Filed: May 11, 2018
    Date of Patent: May 5, 2020
    Assignee: Power Integrations, Inc.
    Inventor: Zhao-Jun Wang
  • Patent number: 10326372
    Abstract: A method for reducing electromagnetic interference in a flyback converter includes activating a first switch to generate a primary current therein. The first switch is deactivated to generate a secondary current from a magnetic flux generated by the primary current. The magnetic flux is removed by the generation of the secondary current. A second switch is activated with a first voltage pulse to limit an excess voltage across the first switch. The excess voltage is generated in response to the deactivation of the first switch. A second switch is activated with a second voltage pulse to limit a voltage oscillation across the first switch. The voltage oscillation occurs after the removal of the magnetic flux. A first pulse width of the first voltage pulse is increased by a first jitter delay. A second pulse width of the second voltage pulse is increased by a second jitter delay.
    Type: Grant
    Filed: May 8, 2018
    Date of Patent: June 18, 2019
    Assignee: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Zhao-Jun Wang, Dibyendu Rana
  • Publication number: 20190044448
    Abstract: A method of providing an input switching request signal to an input side switch includes determining a switching request window indicative of relaxation ringing during a first switching cycle. It is determined that the input side switch is operating in a discontinuous conduction mode (DCM) mode of operation during a second switching cycle. It is determined that the switching request window is open during the second switching cycle. The input switching request signal is enabled in response to determining the switching request window is open.
    Type: Application
    Filed: October 9, 2018
    Publication date: February 7, 2019
    Inventors: Balu Balakrishnan, David Michael Hugh Matthews, Vikram Balakrishnan, Roland Sylvere Saint-Pierre, Zhao-Jun Wang, Giao Minh Pham, Qing McIntosh
  • Publication number: 20180351542
    Abstract: A driver circuit for use in a controller includes a signal generator coupled to generate a first control signal and a second control signal in response to a drive signal that is coupled to control switching of a secondary switch that is to be coupled to the driver circuit and referenced to a reference voltage that is greater than a ground reference voltage. A second switch is coupled to be controlled by the second control signal such that the reference voltage is substantially applied to a control of the secondary switch when the drive signal controls the secondary switch to be off. A first switch is coupled to be controlled by the first control signal such that the sum of the reference voltage and a first voltage is substantially applied to the control of the secondary switch when the drive signal controls the secondary switch on.
    Type: Application
    Filed: May 11, 2018
    Publication date: December 6, 2018
    Applicant: Power Integrations, Inc.
    Inventor: Zhao-Jun Wang
  • Patent number: 10128763
    Abstract: A method for regulating a power converter includes initiating a transition of a switch coupled to an input side of the power converter from an OFF to an ON state to regulate a transfer of energy from the input to an output side of the power converter after a switch control signal generator receives an enable signal and if a feedback signal representative of an output of the power converter indicates a change in an output of the power converter. The enable signal is generated to communicate a control signal from the output to the input side in response to a first signal representative of a voltage on an output terminal that oscillates in response to an ending of the transfer of energy. The transition of the switch from the OFF to the ON state occurs substantially at a time that the first signal reaches an extremum.
    Type: Grant
    Filed: July 13, 2017
    Date of Patent: November 13, 2018
    Assignee: Power Integrations, Inc.
    Inventors: Balu Balakrishnan, David Michael Hugh Matthews, Vikram Balakrishnan, Roland Sylvere Saint-Pierre, Zhao-Jun Wang, Giao Minh Pham, Qing McIntosh
  • Publication number: 20180254710
    Abstract: A method for reducing electromagnetic interference in a flyback converter includes activating a first switch to generate a primary current therein. The first switch is deactivated to generate a secondary current from a magnetic flux generated by the primary current. The magnetic flux is removed by the generation of the secondary current. A second switch is activated with a first voltage pulse to limit an excess voltage across the first switch. The excess voltage is generated in response to the deactivation of the first switch. A second switch is activated with a second voltage pulse to limit a voltage oscillation across the first switch. The voltage oscillation occurs after the removal of the magnetic flux. A first pulse width of the first voltage pulse is increased by a first jitter delay. A second pulse width of the second voltage pulse is increased by a second jitter delay.
    Type: Application
    Filed: May 8, 2018
    Publication date: September 6, 2018
    Applicant: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Zhao-Jun Wang, Dibyendu Rana
  • Patent number: 10027165
    Abstract: An electrical circuit for a power supply includes a primary-side controller integrated circuit (IC) that outputs a drive signal on a switch pin to control a switching operation of a switch that is coupled to a primary winding of a transformer. The primary-side controller IC places the switch pin at high impedance during a sense window and turns on the switch in response to sensing a dynamic detection signal on the switch pin during the sense window. The dynamic detection signal is induced by a secondary-side controller IC by controlling switching of a switch that is coupled to a secondary winding of the transformer when the output voltage drops below a predetermined threshold during standby or other low load conditions.
    Type: Grant
    Filed: May 19, 2017
    Date of Patent: July 17, 2018
    Assignee: FAIRCHILD SEMICONDUCTOR CORPORATION
    Inventors: Zhibo Tao, Zhao-Jun Wang, Chih-Hsien Hsieh, Li Lin
  • Patent number: 9991803
    Abstract: A method for reducing electromagnetic interference in a flyback converter includes activating a first switch to generate a primary current therein. The first switch is deactivated to generate a secondary current from a magnetic flux generated by the primary current. The magnetic flux is removed by the generation of the secondary current. A second switch is activated with a first voltage pulse to limit an excess voltage across the first switch. The excess voltage is generated in response to the deactivation of the first switch. A second switch is activated with a second voltage pulse to limit a voltage oscillation across the first switch. The voltage oscillation occurs after the removal of the magnetic flux. A first pulse width of the first voltage pulse is increased by a first jitter delay. A second pulse width of the second voltage pulse is increased by a second jitter delay.
    Type: Grant
    Filed: January 18, 2017
    Date of Patent: June 5, 2018
    Assignee: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Zhao-Jun Wang, Dibyendu Rana
  • Patent number: 9935556
    Abstract: A method for controlling a resonant converter includes maintaining an output current equal to an output power of the converter divided by an output voltage of the converter in response to a secondary current of a transformer being greater than or equal to a maximum output current. The output power is maintained at a constant output power in response to the output power being greater than or equal to a maximum output power, and the secondary current being less than the maximum output current. Maintaining the output current ratio and the constant output power each comprises changing the duty cycle of a primary-side switch configured to gate a primary current of the transformer. The output voltage is limited to a maximum output voltage in response to the secondary current being less than the maximum output current, and the output power being less than the maximum output power.
    Type: Grant
    Filed: January 27, 2017
    Date of Patent: April 3, 2018
    Assignee: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC
    Inventors: Dibyendu Rana, Zhao-Jun Wang
  • Patent number: 9866125
    Abstract: An ac-dc power converter controller includes a switch driver circuit coupled to generate a drive signal to control switching of a power switch to control a transfer of energy from an input of the power converter to an output of the power converter. An input sense circuit is coupled to receive an input sense signal representative of the input of a power converter. A sense enable circuit is coupled to generate a sense enable signal in response to the drive signal. The sense enable signal is coupled to control the input sense circuit to sense the input sense signal for an extended duration of time after the power switch turns OFF.
    Type: Grant
    Filed: June 22, 2016
    Date of Patent: January 9, 2018
    Assignee: Power Integrations, Inc.
    Inventors: Zhao-Jun Wang, Giao Minh Pham, Roland Sylvere Saint-Pierre