Patents by Inventor King Kuen Hau
King Kuen Hau 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).
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Patent number: 11444603Abstract: A power control circuit comprising a power supply and a load, the load being synthesized from an impedance synthesizer comprising two-terminal impedance elements connected in series and grouped in impedance modules. The impedance elements in each impedance module are of equal value, while those between the modules bear ratios uniquely defined according to the numbers of impedance elements in the impedance modules. A number of switches associated with said impedance elements short out a selected number of the impedance elements under the control of a first analog signal which may be preprocessed by an analytic function. The analog signal is converted to digital signals by an analog-to-digital converter, then level shifted to control the switches associated with the impedance elements, whereby the amount of power delivered to the load is controllable by the first analog signal.Type: GrantFiled: June 1, 2020Date of Patent: September 13, 2022Inventor: King Kuen Hau
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Patent number: 11399421Abstract: Disclosed is a phase-cut dimmer, comprising an AC switch coupled in series between an AC supply and a load; a DC power supply powered from a voltage across the switch; a zero-crossing detector of a phase-cut AC voltage across the switch; a timer generating a timing signal of a duty-cycle proportional to a variable fraction of a peak voltage of a sawtooth signal, wherein the sawtooth signal is synchronized to the zero-crossing detector; a blanking signal generator triggered by a duty-cycle detector to reduce the duty-cycle when the duty-cycle of the timing signal exceeds a predetermined maximum limit; and an operation mode selector activated by an output of an inductive load detector.Type: GrantFiled: May 22, 2019Date of Patent: July 26, 2022Inventor: King Kuen Hau
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Publication number: 20220029535Abstract: A power control circuit comprising a power supply and a load, the load being synthesized from an impedance synthesizer comprising two-terminal impedance elements connected in series and grouped in impedance modules. The impedance elements in each impedance module are of equal value, while those between the modules bear ratios uniquely defined according to the numbers of impedance elements in the impedance modules. A number of switches associated with said impedance elements short out a selected number of the impedance elements under the control of a first analog signal which may be preprocessed by an analytic function. The analog signal is converted to digital signals by an analog-to-digital converter, then level shifted to control the switches associated with the impedance elements, whereby the amount of power delivered to the load is controllable by the first analog signal.Type: ApplicationFiled: June 1, 2020Publication date: January 27, 2022Inventor: King Kuen Hau
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Patent number: 11095230Abstract: A method of AC-to-DC conversion is disclosed, comprising steps of: rectifying an AC voltage to a pulsating DC voltage; coupling the pulsating DC voltage to a capacitor via a switch; coupling an output voltage of the capacitor to a load; monitoring a signal of the load; determining a voltage deviation of the signal of the load from a predetermined reference; in synchronization and in every cycle of the pulsating DC voltage, turning on the switch at a first time instant when the switch is not forward biased and turning off the switch in response to the voltage deviation at a second time instant; whereby the signal of the load is controlled.Type: GrantFiled: June 4, 2018Date of Patent: August 17, 2021Inventor: King Kuen Hau
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Publication number: 20210144826Abstract: Disclosed is a phase-cut dimmer, comprising an AC switch coupled in series between an AC supply and a load; a DC power supply powered from a voltage across the switch; a zero-crossing detector of a phase-cut AC voltage across the switch; a timer generating a timing signal of a duty-cycle proportional to a variable fraction of a peak voltage of a sawtooth signal, wherein the sawtooth signal is synchronized to the zero-crossing detector; a blanking signal generator triggered by a duty-cycle detector to reduce the duty-cycle when the duty-cycle of the timing signal exceeds a predetermined maximum limit; and an operation mode selector activated by an output of an inductive load detector.Type: ApplicationFiled: May 22, 2019Publication date: May 13, 2021Inventor: King Kuen Hau
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Patent number: 10715116Abstract: A power control circuit comprising a power supply and a load, the load being synthesized from an impedance synthesizer comprising two-terminal impedance elements connected in series and grouped in impedance modules. The impedance elements in each impedance module are of equal value, while those between the modules bear ratios uniquely defined according to the numbers of impedance elements in the impedance modules. A number of switches associated with said impedance elements short out a selected number of the impedance elements under the control of a first analog signal which may be preprocessed by an analytic function. The analog signal is converted to digital signals by an analog-to-digital converter, then level shifted to control the switches associated with the impedance elements, whereby the amount of power delivered to the load is controllable by the first analog signal.Type: GrantFiled: March 29, 2017Date of Patent: July 14, 2020Inventor: King Kuen Hau
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Publication number: 20200195162Abstract: A method of AC-to-DC conversion is disclosed, comprising steps of: rectifying an AC voltage to a pulsating DC voltage; coupling the pulsating DC voltage to a capacitor via a switch; coupling an output voltage of the capacitor to a load; monitoring a signal of the load; determining a voltage deviation of the signal of the load from a predetermined reference; in synchronization and in every cycle of the pulsating DC voltage, turning on the switch at a first time instant when the switch is not forward biased and turning off the switch in response to the voltage deviation at a second time instant; whereby the signal of the load is controlled.Type: ApplicationFiled: June 4, 2018Publication date: June 18, 2020Inventor: King Kuen Hau
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Patent number: 10257894Abstract: A phase cut dimmer, coupled between an AC power source and a load, to control the amount of power delivered from the power source to the load, comprising: a dimmer switch to turn on and off the current from the power source to the load; the dimmer switch being an AC switch formed of a first MOSFET and a second MOSFET connected in anti-series; the two source electrodes of the MOSFETs being connected together to form a common source terminal and the two gate electrodes of the MOSFETs being connected together to form a switch control terminal; a line filter bypassing very low current at the line frequency; a rectifier to convert the AC voltage from the power source to pulsating DC voltage which is coupled to the dimmer switch; a very low power unipolar zero detector extracting a zero marker signal from the pulsating DC voltage; the unipolar zero detector comprising a voltage-controlled bleeder impedance, a comparator, a pulse generator, wherein the voltage-controlled bleeder impedance is coupled to the pulsatingType: GrantFiled: July 28, 2015Date of Patent: April 9, 2019Inventor: King Kuen Hau
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Publication number: 20190089336Abstract: A power control circuit comprising a power supply and a load, the load being synthesized from an impedance synthesizer comprising two-terminal impedance elements connected in series and grouped in impedance modules. The impedance elements in each impedance module are of equal value, while those between the modules bear ratios uniquely defined according to the numbers of impedance elements in the impedance modules. A number of switches associated with said impedance elements short out a selected number of the impedance elements under the control of a first analog signal which may be preprocessed by an analytic function. The analog signal is converted to digital signals by an analog-to-digital converter, then level shifted to control the switches associated with the impedance elements, whereby the amount of power delivered to the load is controllable by the first analog signal.Type: ApplicationFiled: March 29, 2017Publication date: March 21, 2019Inventor: King Kuen HAU
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Patent number: 9791878Abstract: A high-efficiency digital voltage controller capable of providing monotonically-varying stepwise voltage, said controller comprises of a plurality of two-terminal voltage modules connected in series; within each module one or more two-terminal voltage cells of identical voltage each and connected in series; within each module a plurality of switches controllable to connect any number of the voltage cells in series to the output terminals of the voltage module; the ratios of the magnitudes of voltage of any one voltage cell between the voltage modules being substantially equal to integer values uniquely defined by present invention, according to the numbers of voltage cells in each of the voltage modules; said plurality of switches being controlled by a control module implemented in any suitable logic.Type: GrantFiled: August 2, 2013Date of Patent: October 17, 2017Inventor: King Kuen Hau
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Publication number: 20170208659Abstract: A phase cut dimmer, coupled between an AC power source and a load, to control the amount of power delivered from the power source to the load, comprising: a dimmer switch to turn on and off the current from the power source to the load; the dimmer switch being an AC switch formed of a first MOSFET and a second MOSFET connected in anti-series; the two source electrodes of the MOSFETs being connected together to form a common source terminal and the two gate electrodes of the MOSFETs being connected together to form a switch control terminal; a line filter bypassing very low current at the line frequency; a rectifier to convert the AC voltage from the power source to pulsating DC voltage which is coupled to the dimmer switch; a very low power unipolar zero detector extracting a zero marker signal from the pulsating DC voltage; the unipolar zero detector comprising a voltage-controlled bleeder impedance, a comparator, a pulse generator, wherein the voltage-controlled bleeder impedance is coupled to the pulsatingType: ApplicationFiled: July 28, 2015Publication date: July 20, 2017Inventor: King Kuen HAU
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Patent number: 9543925Abstract: A voltage controlled impedance synthesizer providing stepwise variable impedance values according to a prescribed function of the control voltage, said synthesizer comprises of one or more two-terminal impedance modules connected in series, in each impedance module one or more essentially identical two-terminal impedance elements connected in series, a corresponding number of switches to short out by selection none to all of the impedance elements in the impedance module, and said switches being controlled by the control voltage through analog-to-digital conversion and digital processing means. The values of the impedance elements between the impedance modules in ratios being uniquely defined according to the numbers of impedance elements in the impedance modules, the voltage controlled impedance synthesizer is controlled to provide monotonic and stepwise variable impedance values.Type: GrantFiled: September 3, 2013Date of Patent: January 10, 2017Inventor: King Kuen Hau
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Publication number: 20150241900Abstract: A high-efficiency digital voltage controller capable of providing monotonically-varying stepwise voltage, said controller comprises of a plurality of two-terminal voltage modules connected in series; within each module one or more two-terminal voltage cells of identical voltage each and connected in series; within each module a plurality of switches controllable to connect any number of the voltage cells in series to the output terminals of the voltage module; the ratios of the magnitudes of voltage of any one voltage cell between the voltage modules being substantially equal to integer values uniquely defined by present invention, according to the numbers of voltage cells in each of the voltage modules; said plurality of switches being controlled by a control module implemented in any suitable logic.Type: ApplicationFiled: August 2, 2013Publication date: August 27, 2015Inventor: King Kuen HAU
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Publication number: 20150229294Abstract: A voltage controlled impedance synthesizer providing stepwise variable impedance values according to a prescribed function of the control voltage, said synthesizer comprises of one or more two-terminal impedance modules connected in series, in each impedance module one or more essentially identical two-terminal impedance elements connected in series, a corresponding number of switches to short out by selection none to all of the impedance elements in the impedance module, and said switches being controlled by the control voltage through analog-to-digital conversion and digital processing means. The values of the impedance elements between the impedance modules in ratios being uniquely defined according to the numbers of impedance elements in the impedance modules, the voltage controlled impedance synthesizer is controlled to provide monotonic and stepwise variable impedance values.Type: ApplicationFiled: September 3, 2013Publication date: August 13, 2015Inventor: King Kuen Hau