Patents by Inventor Cha-fu Tsai

Cha-fu Tsai 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).

  • Patent number: 11632053
    Abstract: An isolated switched-mode power converter converts power from an input source into power for an output load. A digital controller senses a secondary-side voltage, such as a rectified voltage, of the power converter. The secondary-side voltage is divided down using a high-impedance voltage divider. The resultant divided-down voltage is provided to a voltage sensor within the digital controller. The voltage sensor level shifts the provided voltage, and buffers the resulting level-shifted voltage. The buffered, level-shifted voltage is provided to a tracking analog-to-digital converter (ADC) for digitization. The buffered signal provided to the tracking ADC has a high current capability, such that the voltage input to the tracking ADC may quickly converge before the tracking ADC outputs a digital value for the sensed secondary-side voltage.
    Type: Grant
    Filed: September 1, 2020
    Date of Patent: April 18, 2023
    Assignee: Infineon Technologies Austria AG
    Inventors: Sujata Sen, Ronald Hulfachor, Sue Perranoski, Cha-Fu Tsai
  • Patent number: 11411500
    Abstract: A controller for a power converter includes: a first sense terminal and a second sense terminal for sensing an output voltage of the power converter; a bridging circuit configured to electrically couple the first sense terminal to the second sense terminal in a first state and electrically decouple the first sense terminal from the second sense terminal in a second state; and control circuitry configured to set the bridging circuit in the first state during a portion of a voltage ramp of the power converter, and to determine whether an open or short fault condition is present at either the first sense terminal or the second sense terminal based on a voltage across the bridging circuit in the first state.
    Type: Grant
    Filed: November 12, 2019
    Date of Patent: August 9, 2022
    Assignee: Infineon Technologies Austria AG
    Inventors: Mattia Oddicini, Kelsey Curtis, Tim Ng, Cha-Fu Tsai
  • Publication number: 20210143740
    Abstract: A controller for a power converter includes: a first sense terminal and a second sense terminal for sensing an output voltage of the power converter; a bridging circuit configured to electrically couple the first sense terminal to the second sense terminal in a first state and electrically decouple the first sense terminal from the second sense terminal in a second state; and control circuitry configured to set the bridging circuit in the first state during a portion of a voltage ramp of the power converter, and to determine whether an open or short fault condition is present at either the first sense terminal or the second sense terminal based on a voltage across the bridging circuit in the first state.
    Type: Application
    Filed: November 12, 2019
    Publication date: May 13, 2021
    Inventors: Mattia Oddicini, Kelsey Curtis, Tim Ng, Cha-Fu Tsai
  • Publication number: 20200395864
    Abstract: An isolated switched-mode power converter converts power from an input source into power for an output load. A digital controller senses a secondary-side voltage, such as a rectified voltage, of the power converter. The secondary-side voltage is divided down using a high-impedance voltage divider. The resultant divided-down voltage is provided to a voltage sensor within the digital controller. The voltage sensor level shifts the provided voltage, and buffers the resulting level-shifted voltage. The buffered, level-shifted voltage is provided to a tracking analog-to-digital converter (ADC) for digitization. The buffered signal provided to the tracking ADC has a high current capability, such that the voltage input to the tracking ADC may quickly converge before the tracking ADC outputs a digital value for the sensed secondary-side voltage.
    Type: Application
    Filed: September 1, 2020
    Publication date: December 17, 2020
    Inventors: Sujata Sen, Ronald Hulfachor, Sue Perranoski, Cha-Fu Tsai
  • Patent number: 10770983
    Abstract: An isolated switched-mode power converter converts power from an input source into power for an output load. A digital controller senses a secondary-side voltage, such as a rectified voltage, of the power converter. The secondary-side voltage is divided down using a high-impedance voltage divider. The resultant divided-down voltage is provided to a voltage sensor within the digital controller. The voltage sensor level shifts the provided voltage, and buffers the resulting level-shifted voltage. The buffered, level-shifted voltage is provided to a tracking analog-to-digital converter (ADC) for digitization. The buffered signal provided to the tracking ADC has a high current capability, such that the voltage input to the tracking ADC may quickly converge before the tracking ADC outputs a digital value for the sensed secondary-side voltage.
    Type: Grant
    Filed: December 6, 2018
    Date of Patent: September 8, 2020
    Assignee: Infineon Technologies Austria AG
    Inventors: Sujata Sen, Ronald Hulfachor, Sue Perranoski, Cha-Fu Tsai
  • Publication number: 20200186047
    Abstract: An isolated switched-mode power converter converts power from an input source into power for an output load. A digital controller senses a secondary-side voltage, such as a rectified voltage, of the power converter. The secondary-side voltage is divided down using a high-impedance voltage divider. The resultant divided-down voltage is provided to a voltage sensor within the digital controller. The voltage sensor level shifts the provided voltage, and buffers the resulting level-shifted voltage. The buffered, level-shifted voltage is provided to a tracking analog-to-digital converter (ADC) for digitization. The buffered signal provided to the tracking ADC has a high current capability, such that the voltage input to the tracking ADC may quickly converge before the tracking ADC outputs a digital value for the sensed secondary-side voltage.
    Type: Application
    Filed: December 6, 2018
    Publication date: June 11, 2020
    Inventors: Sujata Sen, Ronald Hulfachor, Sue Perranoski, Cha-Fu Tsai
  • Patent number: 9397645
    Abstract: In one example, a method includes receiving a first differential signal including a first voltage signal and a second voltage signal, wherein the first differential signal includes a first common mode voltage; receiving a second common mode voltage. The method further includes determining, by a circuit, a second differential signal including a third voltage signal and a fourth voltage signal, wherein a difference between the third voltage signal and the fourth voltage signal is based on a difference between the first voltage signal and the second voltage signal, wherein the second differential signal includes the second common mode voltage. The method further includes outputting, substantially continuously, the second differential signal.
    Type: Grant
    Filed: March 25, 2014
    Date of Patent: July 19, 2016
    Assignee: Infineon Technologies Austria AG
    Inventors: Giuseppe Bernacchia, Cha-fu Tsai
  • Publication number: 20150280696
    Abstract: In one example, a method includes receiving a first differential signal including a first voltage signal and a second voltage signal, wherein the first differential signal includes a first common mode voltage; receiving a second common mode voltage. The method further includes determining, by a circuit, a second differential signal including a third voltage signal and a fourth voltage signal, wherein a difference between the third voltage signal and the fourth voltage signal is based on a difference between the first voltage signal and the second voltage signal, wherein the second differential signal includes the second common mode voltage. The method further includes outputting, substantially continuously, the second differential signal.
    Type: Application
    Filed: March 25, 2014
    Publication date: October 1, 2015
    Applicants: Infineon Technologies North America Corp., Infineon Technologies Austria AG
    Inventors: Giuseppe Bernacchia, Cha-fu Tsai