Patents by Inventor Isaac Y. Chen

Isaac Y. Chen 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: 20180309385
    Abstract: The invention provides a power conversion device, including: a voltage conversion stage, including a primary side for receiving a rectified voltage and a secondary side for generating a rectified voltage according to the rectified voltage, wherein the primary side includes a primary side switch; a switch control circuit having a startup status and a normal operation status, the switch control circuit being configured to operably provide a control signal to a control terminal of the primary side switch; a startup circuit, providing a current to the control terminal when the switch control circuit is in the startup status, to at least partially conduct the primary side switch; and a slow soft-startup circuit, wherein when the switch control circuit is in the startup status and the output voltage does not reach a predetermined voltage in a first predetermined time period, the slow soft-startup circuit reduces a total current quantity supplied to the control terminal in a second predetermined time period which is
    Type: Application
    Filed: June 24, 2017
    Publication date: October 25, 2018
    Inventors: Jyun-Che Ho, Isaac Y. Chen, Yi-Wei Lee
  • Publication number: 20180301993
    Abstract: A power converter determines a feedback signal according to a voltage signal related to an output voltage of the power converter and a reference voltage, thereby regulating the output voltage. A control circuit and method for programming the output voltage of the power converter utilize an offset current generator to inject a current or sink a current for changing the voltage signal or the reference signal, thereby adjusting the output voltage. As a result, it gets rid of complicated circuitry but provides more steps adjustment, which reduces related costs.
    Type: Application
    Filed: June 19, 2018
    Publication date: October 18, 2018
    Inventor: ISAAC Y. CHEN
  • Publication number: 20180301994
    Abstract: A power converter determines a feedback signal according to a voltage signal related to an output voltage of the power converter and a reference voltage, thereby regulating the output voltage. A control circuit and method for programming the output voltage of the power converter utilize an offset current generator to inject a current or sink a current for changing the voltage signal or the reference signal, thereby adjusting the output voltage. As a result, it gets rid of complicated circuitry but provides more steps adjustment, which reduces related costs.
    Type: Application
    Filed: June 20, 2018
    Publication date: October 18, 2018
    Inventor: ISAAC Y. CHEN
  • Patent number: 10097094
    Abstract: A power converter determines a feedback signal according to a voltage signal related to an output voltage of the power converter and a reference voltage, thereby regulating the output voltage. A control circuit and method for programming the output voltage of the power converter utilize an offset current generator to inject a current or sink a current for changing the voltage signal or the reference signal, thereby adjusting the output voltage. As a result, it gets rid of complicated circuitry but provides more steps adjustment, which reduces related costs.
    Type: Grant
    Filed: October 22, 2015
    Date of Patent: October 9, 2018
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventor: Isaac Y. Chen
  • Patent number: 10097092
    Abstract: A multi-phase switching regulator includes: a plurality of power stages, a plurality of pulse width modulation (PWM) controllers and a ramp signal setting circuit. The PWM controllers generate corresponding PWM signals for controlling corresponding power stages respectively according to an error signal related to an output voltage and a plurality of ramp signals corresponding to corresponding power stages respectively. The ramp signal setting circuit adjusts the ramp signal of the phase that is to be enabled or disabled according to the phase adjustment signal. Under a phase-cut operation, the ramp signal setting circuit causes a basis level of the ramp signal corresponding to the phase to be disabled to gradually change, thereby decreasing a duty ratio of the PWM signal corresponding to the phase to be disabled.
    Type: Grant
    Filed: March 4, 2018
    Date of Patent: October 9, 2018
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Jyun-Che Ho, Yu-Chang Chen, Jo-Yu Wang, Yi-Wei Lee, Isaac Y. Chen
  • Publication number: 20180233937
    Abstract: An adaptive buck converter of a charging cable includes: a power receiving interface for receiving a DC voltage and a cable current from a cable; a terminal communication interface for transmitting a charging voltage and a charging current to a connection terminal of the charging cable and for receiving a communication signal generated by a mobile device from the connection terminal; a power converting circuit for receiving the DC voltage and the cable current from the power receiving interface and for generating the charging voltage and the charging current; a monitor circuit arranged to operably detect the DC voltage or the cable current; and a data processing circuit configured for controlling the power converting circuit according to the communication signal. The data processing circuit further communicates with the mobile device through the terminal communication interface and the connection terminal in response to a detection result of the monitor circuit.
    Type: Application
    Filed: April 12, 2018
    Publication date: August 16, 2018
    Applicant: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Ta-Yung YANG, Jing-Meng LIU, Isaac Y. CHEN, Tzu-Chen LIN
  • Publication number: 20180212528
    Abstract: A flyback power converter circuit converting an input voltage to an output voltage includes a transformer, a power switch, a synchronous rectifier (SR) switch, and a secondary side control circuit. The secondary side control circuit controls the SR switch to be ON when the power switch is OFF. The secondary side control circuit includes a driving switch for controlling the SR switch, a synchronous control circuit powered by a voltage related to the output voltage, which controls the driving switch to operate the SR switch, and a clamping circuit including a clamping switch and a clamping switch control circuit. The clamping switch control circuit controls the clamping switch according to a current inflow terminal voltage of the clamping switch and/or the voltage related to the output voltage, such that, during a secondary side power-on period, an equivalent impedance of the current inflow terminal of the clamping switch is smaller than a predetermined clamping impedance.
    Type: Application
    Filed: January 8, 2018
    Publication date: July 26, 2018
    Inventors: Chien-Fu Tang, Su-Yuan Lin, Yi-Wei Lee, Isaac Y. Chen
  • Patent number: 10014783
    Abstract: The present invention provides a switching regulator with PFC function and a control circuit and a control method thereof. The switching regulator with PFC function includes a power stage circuit, a current sense circuit, and a control circuit. The power stage circuit operates at least one power switch therein according to an operation signal to convert an input voltage to an output voltage. When a transient voltage of the input voltage exceeds a transient voltage upper limit, or when a transient slew rate of the input voltage exceeds a transient slew rate upper limit, the control circuit adjusts a frequency response gain from a stable state frequency response gain to a transient state frequency response gain, such that a transient current of an output current does not exceed a current upper limit, and/or that a transient response time of the output current does not exceed a threshold transient time period.
    Type: Grant
    Filed: December 30, 2016
    Date of Patent: July 3, 2018
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Yi-Wei Lee, Chien-Yang Chen, Isaac Y. Chen, Ta-Yung Yang
  • Publication number: 20180159423
    Abstract: The present invention discloses a short circuit and/or bad connection detection method for use in a power supply system. The power supply system includes a power converter which converts an input voltage to an output voltage and supplies an output current to an electronic device. In the short circuit detection method, the conversion from the input voltage to the output voltage is disabled in a disable time period, and whether a short circuit occurs is determined according to the decreasing speed of the output voltage. In the bad connection detection method, an actual voltage and an actual current received by the electronic device are compared with the output voltage and the output current, to determine whether a bad connection occurs.
    Type: Application
    Filed: January 18, 2018
    Publication date: June 7, 2018
    Inventors: Yi-Min Shiu, Isaac Y. Chen
  • Patent number: 9979214
    Abstract: An adaptive buck converter of a charging cable includes: a power receiving interface for receiving a DC voltage and a cable current from a cable; a terminal communication interface for transmitting a charging voltage and a charging current to a connection terminal of the charging cable and for receiving a communication signal generated by the mobile device from the connection terminal; a power converting circuit for receiving the DC voltage and the cable current from the power receiving interface and for generating the charging voltage and the charging current, wherein the charging voltage is lower than the DC voltage while the charging current is greater than the cable current; and a data processing circuit coupled with the power converting circuit and configured for controlling the power converting circuit according to the communication signal.
    Type: Grant
    Filed: February 2, 2016
    Date of Patent: May 22, 2018
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Ta-Yung Yang, Jing-Meng Liu, Isaac Y. Chen, Tzu-Chen Lin
  • Publication number: 20180138797
    Abstract: The present invention provides a power switch control circuit and an open detection method thereof. The power switch control circuit is for generating an operation signal at an operation signal output pin according to an input signal, wherein the operation signal is for operating a power switch. The power switch control circuit includes: a current injection circuit, which is connected to the operation signal output pin, and provides a predetermined current to the operation signal output pin according to an enable signal; and an open detection circuit, which is coupled to the current injection circuit, and determines whether a connection between the operation signal output pin and the power switch is open according to a level of the operation signal output pin at a detection time point or according to a level variation of the operation signal output pin during a detection time period, whereby an open detection signal is generated.
    Type: Application
    Filed: April 11, 2017
    Publication date: May 17, 2018
    Inventors: Pei-Sheng Tsu, Chien-Fu Tang, Isaac Y. Chen
  • Patent number: 9964972
    Abstract: A mixed mode compensation circuit for a power converter generate a digital signal according to a reference signal and a feedback signal which is related to the output voltage of the power converter, convert the digital signal into a first analog signal, offset the first analog signal with a variable offset value to generate a second analog signal, and filter out high-frequency components of the second analog signal to generate a third analog signal for stable output voltage of the power converter. The mixed mode compensation does not require large capacitors, and thus the circuit can be integrated into an integrated circuit.
    Type: Grant
    Filed: July 3, 2016
    Date of Patent: May 8, 2018
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Chien-Fu Tang, Jiun-Hung Pan, Isaac Y. Chen
  • Patent number: 9966857
    Abstract: An AC-to-DC power converter with a BJT as a power switch can set a base current of the BJT by a current setting resistor which is in the outside of a control integrated circuit. Since an output current and a recovery current of the BJT are injected into a sensing resistor, the AC-to-DC power converter can correctly detect an inductor current thereof from the sensing resistor.
    Type: Grant
    Filed: June 24, 2016
    Date of Patent: May 8, 2018
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Jiun-Hung Pan, Chien-Fu Tang, Jyun-Che Ho, Isaac Y. Chen, Yu-Chang Chen, Jung-Pei Cheng
  • Patent number: 9912224
    Abstract: The present invention discloses a short circuit and/or bad connection detection method for use in a power supply system. The power supply system includes a power converter which converts an input voltage to an output voltage and supplies an output current to an electronic device. In the short circuit detection method, the conversion from the input voltage to the output voltage is disabled in a disable time period, and whether a short circuit occurs is determined according to the decreasing speed of the output voltage. In the bad connection detection method, an actual voltage and an actual current received by the electronic device are compared with the output voltage and the output current, to determine whether a bad connection occurs.
    Type: Grant
    Filed: June 10, 2015
    Date of Patent: March 6, 2018
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Yi-Min Shiu, Isaac Y. Chen
  • Patent number: 9871453
    Abstract: A feedback signal stabilized by a capacitor and related to an output voltage of a power converter is used to acquire the output power information of the power converter, and a control circuit uses a second clock not related to the switching frequency of the power converter to count a duration time of the feedback signal being higher than a threshold. When the duration time is higher than a preset time, an abnormal output power of the power converter is distinguished and the power converter will be turned off. The feedback signal will not vary severely even if the output terminal of the power converter is interfered, and the counted duration time will not be influenced when the switching frequency is changing caused by a load changing.
    Type: Grant
    Filed: September 16, 2016
    Date of Patent: January 16, 2018
    Assignee: Richtek Technology Corp.
    Inventor: Isaac Y. Chen
  • Publication number: 20170331381
    Abstract: The present invention provides a switching regulator with PFC function and a control circuit and a control method thereof. The switching regulator with PFC function includes a power stage circuit, a current sense circuit, and a control circuit. The power stage circuit operates at least one power switch therein according to an operation signal to convert an input voltage to an output voltage. When a transient voltage of the input voltage exceeds a transient voltage upper limit, or when a transient slew rate of the input voltage exceeds a transient slew rate upper limit, the control circuit adjusts a frequency response gain from a stable state frequency response gain to a transient state frequency response gain, such that a transient current of an output current does not exceed a current upper limit, and/or that a transient response time of the output current does not exceed a threshold transient time period.
    Type: Application
    Filed: December 30, 2016
    Publication date: November 16, 2017
    Inventors: Yi-Wei Lee, Chien-Yang Chen, Isaac Y. Chen, Ta-Yung Yang
  • Patent number: 9781786
    Abstract: A control circuit of a LED driver utilizes a counter to acquire a cycle and a conduction time or a non-conduction time of an AC phase-cut voltage outputted by a TRIAC dimmer. A bleeding signal is determined according to the cycle and the conduction time or the non-conduction time and used for adjusting a bleeding current so as to avoid a flickering of the LED. The control circuit does not need extra pins for coupling a large capacitor, but the bleeding signal can be still acquired. Preferably, the present invention is suitable for an IC of low pin numbers.
    Type: Grant
    Filed: January 27, 2016
    Date of Patent: October 3, 2017
    Assignee: RICHTEK TECHNOLOGY CORP.
    Inventors: Jyun-Che Ho, Isaac Y. Chen, Yi-Wei Lee
  • Patent number: 9755511
    Abstract: The present invention discloses a current regulator circuit capable of reducing current ripple and a method of reducing current ripple. A power supply circuit generates a load current which originally has a current ripple. The load current is supplied to a load circuit. The current regulator circuit includes a regulator switch coupled to the load circuit, a current sense circuit for sensing the load current, and a control circuit. The control circuit controls the regulator switch to regulate a peak of a current sense signal minus an average of the current sense signal to a non-negative first predetermined value, or regulate the peak minus a valley of the current sense signal to a non-negative second predetermined value.
    Type: Grant
    Filed: March 22, 2016
    Date of Patent: September 5, 2017
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Yi-Wei Lee, Isaac Y. Chen
  • Publication number: 20170201101
    Abstract: An adaptive charging voltage generator of a mobile device charger includes: a power receiving interface for receiving a DC voltage and a cable current from a cable; a terminal communication interface for transmitting a charging voltage and a charging current to a connection terminal of the mobile device charger and for receiving a communication signal generated by the mobile device from the connection terminal; a buck converter for receiving the DC voltage and the cable current from the power receiving interface and for generating the charging voltage and the charging current, wherein the charging voltage is lower than the DC voltage while the charging current is greater than the cable current; and a charging voltage control circuit coupled with the buck converter and configured for controlling the buck converter according to the communication signal.
    Type: Application
    Filed: February 2, 2016
    Publication date: July 13, 2017
    Applicant: Richtek Technology Corporation
    Inventors: Ta-Yung YANG, Jing-Meng LIU, Isaac Y. CHEN, Tzu-Chen LIN
  • Publication number: 20170201107
    Abstract: An adaptive buck converter of a charging cable includes: a power receiving interface for receiving a DC voltage and a cable current from a cable; a terminal communication interface for transmitting a charging voltage and a charging current to a connection terminal of the charging cable and for receiving a communication signal generated by the mobile device from the connection terminal; a power converting circuit for receiving the DC voltage and the cable current from the power receiving interface and for generating the charging voltage and the charging current, wherein the charging voltage is lower than the DC voltage while the charging current is greater than the cable current; and a data processing circuit coupled with the power converting circuit and configured for controlling the power converting circuit according to the communication signal.
    Type: Application
    Filed: February 2, 2016
    Publication date: July 13, 2017
    Applicant: Richtek Technology Corporation
    Inventors: Ta-Yung YANG, Jing-Meng LIU, Isaac Y. CHEN, Tzu-Chen LIN