Patents by Inventor Yuan-Huang Cheng

Yuan-Huang Cheng 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: 8643354
    Abstract: The present invention discloses a multi-phase switching regulator, a driver circuit of a multi-phase switching regulator, and a control method of a multi-phase switching regulator. The multi-phase switching regulator includes: at least two power stages, switching power transistors in the power stages to convert an input voltage to an output voltage according to pulse width modulation (PWM) signals generated by corresponding PWM controllers respectively; and a current balance circuit, generating a current balance signal according to the current of the corresponding power stage and a phase adjustment signal to averagely distribute current over the active power stages. In the present invention, the gain of the current balance circuit is adjustable, to avoid or reduce output voltage overshoot and undershoot when the phase number changes, while the current balance function is still achieved in normal operation.
    Type: Grant
    Filed: May 26, 2011
    Date of Patent: February 4, 2014
    Assignee: Richtek Technology Corporation, R.O.C.
    Inventors: Yu-Wei Chang, Yuan-Huang Cheng, Ting-Hung Wang, Chia-Jung Lee, Chung-Sheng Cheng
  • Publication number: 20120176105
    Abstract: The present invention discloses a multi-phase switching regulator, a driver circuit of a multi-phase switching regulator, and a control method of a multi-phase switching regulator. The multi-phase switching regulator includes: at least two power stages, switching power transistors in the power stages to convert an input voltage to an output voltage according to pulse width modulation (PWM) signals generated by corresponding PWM controllers respectively; and a current balance circuit, generating a current balance signal according to the current of the corresponding power stage and a phase adjustment signal to averagely distribute current over the active power stages. In the present invention, the gain of the current balance circuit is adjustable, to avoid or reduce output voltage overshoot and undershoot when the phase number changes, while the current balance function is still achieved in normal operation.
    Type: Application
    Filed: May 26, 2011
    Publication date: July 12, 2012
    Inventors: Yu-Wei Chang, Yuan-Huang Cheng, Ting-Hung Wang, Chia-Jung Lee, Chung-Sheng Cheng
  • Publication number: 20120086418
    Abstract: The present invention discloses a multi-phase switching regulator, and a driver circuit and a control method thereof. The multi-phase switching regulator includes: at least two power stages each having at least one switching power transistor which switches to convert a common input voltage to a common output voltage according to PWM signals generated by corresponding PWM controllers, respectively; a feedback circuit, generating a feedback signal according to the output voltage; a current balance circuit, generating a current balance signal according to the currents of the power stages and a phase off signal to distribute current loading among the active power stages; and a soft shutdown control circuit, generating a soft shutdown control signal according to the phase off signal to gradually change the duty of a PWM signal corresponding to a power stage, so as to softly shut down the power stage to avoid a voltage undershoot.
    Type: Application
    Filed: January 27, 2011
    Publication date: April 12, 2012
    Inventors: Chia-Jung Lee, Yuan-Huang Cheng, Ting-Hung Wang
  • Patent number: 7518888
    Abstract: In a fly-back voltage converter that includes a transformer to transform a primary current to a secondary current and a switch serially coupled to the primary winding to switch the primary current in response to a control signal, a detection signal is produced by comparing the secondary current with two threshold values after the primary current is switched off to trigger the next on-time cycle of the switch. Once the secondary current is detected to be greater than a first threshold value, it is determined that the secondary current has been switched on, and until the secondary current is detected to be lower than a second threshold value, it is determined that the secondary current is to be switched off. The hysteresis range of the threshold values prevents error detection of the secondary current.
    Type: Grant
    Filed: May 2, 2006
    Date of Patent: April 14, 2009
    Assignee: Richtek Technology Corp.
    Inventors: Kwan-Jen Chu, Chung-Lung Pai, Yuan-Huang Cheng, Jing-Meng Liu
  • Publication number: 20070118311
    Abstract: In a capacitor charger including a transformer to transform a primary coil voltage to a secondary coil voltage to charge a capacitor at an output through a charging node to approach a predetermined voltage, a voltage sense apparatus and method comprise sensing the voltage on the capacitor with a voltage divider to generate a feedback signal to stop charging the capacitor when the capacitor voltage is sensed to be equal to or higher than the predetermined voltage, and preventing an inverse current flowing from the capacitor to the charging node for no leakage occurred from the capacitor to the voltage sense apparatus.
    Type: Application
    Filed: January 11, 2007
    Publication date: May 24, 2007
    Inventor: Yuan-Huang Cheng
  • Publication number: 20060250827
    Abstract: In a fly-back voltage converter that includes a transformer to transform a primary current to a secondary current and a switch serially coupled to the primary winding to switch the primary current in response to a control signal, a detection signal is produced by comparing the secondary current with two threshold values after the primary current is switched off to trigger the next on-time cycle of the switch. Once the secondary current is detected to be greater than a first threshold value, it is determined that the secondary current has been switched on, and until the secondary current is detected to be lower than a second threshold value, it is determined that the secondary current is to be switched off. The hysteresis range of the threshold values prevents error detection of the secondary current.
    Type: Application
    Filed: May 2, 2006
    Publication date: November 9, 2006
    Inventors: Kwan-Jen Chu, Chung-Lung Pai, Yuan-Huang Cheng, Jing-Meng Liu
  • Publication number: 20060002162
    Abstract: A capacitor charger comprises an inductor connected between an input voltage and an output capacitor, a taper drawn from the inductor to separate the inductor to two segments, and a switch connected to the taper, and switches the switch to produce a current to charge the output capacitor to produce an output voltage thereon.
    Type: Application
    Filed: June 28, 2005
    Publication date: January 5, 2006
    Inventors: Rong-Jie Tu, Yuan-Huang Cheng
  • Publication number: 20050285573
    Abstract: In a capacitor charger including a transformer to transform a primary coil voltage to a secondary coil voltage to charge a capacitor at an output through a charging node to approach a predetermined voltage, a voltage sense apparatus and method comprise sensing the voltage on the capacitor with a voltage divider to generate a feedback signal to stop charging the capacitor when the capacitor voltage is sensed to be equal to or higher than the predetermined voltage, and preventing an inverse current flowing from the capacitor to the charging node for no leakage occurred from the capacitor to the voltage sense apparatus.
    Type: Application
    Filed: June 27, 2005
    Publication date: December 29, 2005
    Inventor: Yuan-Huang Cheng