Patents Examined by Rajnikant B. Patel
  • Mutual blanking for a multi-channel converter
    Patent number: 7956585
    Abstract: A shutter circuit is provided for a multi-channel converter to blank the switching noise produced by the switching of the converter. The shutter circuit monitors the switching of the switches in the output stages of the converter, and when one channel performs switching, the shutter circuit will send a signal to other channels to block the current sensors thereof. The current sensors are so blocked for a period not to sense the switching noise. The mutual interference between the channels due to the switching noise of the converter is eliminated.
    Type: Grant
    Filed: July 10, 2008
    Date of Patent: June 7, 2011
    Assignee: Richtek Technology Corp.
    Inventors: An-Tung Chen, Jun-Yao Huang, Fu-Shiang Lai
  • Feedback circuit for DC/AC inverter
    Patent number: 7952296
    Abstract: A feedback circuit is utilized in a DC/AC inverter having a first power switch and a second power switch for driving a fluorescent lamp. The feedback circuit includes a protection circuit for disabling the first power switch and the second power switch when no fluorescent lamp is electrically connected, a first capacitor having a first terminal electrically connected to an output of the DC/AC inverter, a second capacitor having a first terminal electrically connected to a ground, and a second terminal electrically connected to a second terminal of the first capacitor, a diode having an anode electrically connected to the second terminals of the first and second capacitors, and a cathode electrically connected to the protection circuit, and a first resistor having a first terminal electrically connected to the cathode of the diode, and a second terminal electrically connected to the ground.
    Type: Grant
    Filed: January 25, 2010
    Date of Patent: May 31, 2011
    Assignee: Beyond Innovation Techology Co., Ltd.
    Inventors: Chung-Che Yu, Shih-Chung Huang, Chien-Pang Hung, Chih-Shun Lee
  • Multi-stable electronic circuit state control
    Patent number: 7952341
    Abstract: Apparatus and methods of controlling operating states of multi-stable electronic circuits are disclosed. In one aspect, an apparatus includes a bandgap reference circuit having an operating state and a latched off state. The bandgap reference circuit includes an amplifier to provide a bandgap reference voltage when the bandgap reference circuit is in the operating state. A state control circuit is also included and is coupled to sense an output signal of the bandgap reference circuit. The state control circuit is also coupled to provide a drive signal to an input of the amplifier in response to the sensed output signal. The drive signal is coupled to cause the bandgap reference circuit to avoid the latched off state.
    Type: Grant
    Filed: June 11, 2008
    Date of Patent: May 31, 2011
    Assignee: Power Integrations, Inc.
    Inventor: Frank Joseph Schulz
  • Electric power converter
    Patent number: 7952876
    Abstract: The present invention provides a highly reliable electric power converter reduced in parasitic inductance.
    Type: Grant
    Filed: March 1, 2010
    Date of Patent: May 31, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Katsunori Azuma, Mutsuhiro Mori, Kinya Nakatsu
  • Silicon interposer-based hybrid voltage regulator system for VLSI devices
    Patent number: 7952194
    Abstract: A voltage regulation module and system for an integrated circuit die. The voltage regulation module includes an interposer situated in a stack between a substrate and the integrated circuit die. The interposer includes a hybrid array of voltage regulation elements for receiving voltage from the power supply and for down-converting the voltage from the power supply into a regulated voltage supplied to the integrated circuit die. The hybrid array of voltage regulation elements includes both high-bandwidth linear regulation elements for providing voltage regulation to areas on the integrated circuit die that intermittently demand relatively high current levels, and low-bandwidth switching regulator elements that are highly power efficient.
    Type: Grant
    Filed: October 26, 2001
    Date of Patent: May 31, 2011
    Assignee: Intel Corporation
    Inventors: Raj Nair, Johanna Swan, Bala Natarajan, Mark Bohr
  • Control of a resonant converter
    Patent number: 7944716
    Abstract: The invention deals with the control of a resonant LLC converter by use of control parameters. The primary current flowing in the resonant tank and a voltage at a predetermined point in the resonant tank are monitored and control parameters are set for a high side conduction interval and control parameters are set for a low side conduction interval, the control parameters for the two conduction intervals being: a peak current of the interval and a predetermined voltage of the interval. The resonant converter comprises series-arranged controllable switches to be connected to the supply source. The resonant converter is operated by setting up criteria for turning off a switch in accordance with criteria including the four control parameters.
    Type: Grant
    Filed: March 24, 2006
    Date of Patent: May 17, 2011
    Assignee: NXP B.V.
    Inventor: Hans Halberstadt
  • Semiconductor integrated circuit, PWM signal output device, and power conversion control apparatus
    Patent number: 7944720
    Abstract: Provided is a control technique of a PWM conversion type power converter capable of compensating for a voltage error due to voltage drop mainly at a switching element and managing a switching time of a PWM signal at the same time, and capable of suppressing increase/decrease of software operation load and addition of a hardware circuit to the minimum. A semiconductor integrated circuit having a PWM signal generating unit which generates a PWM signal is provided with a PWM timer unit including a counter counting a pulse width of a pulse signal inputted from the outside with delay from a PWM signal, a register loading a counter value of the counter in synchronization with the PWM signal, and an A/D converting unit converting an analog signal serving as a source signal of the pulse signal inputted from the outside to a digital signal.
    Type: Grant
    Filed: August 14, 2008
    Date of Patent: May 17, 2011
    Assignee: Renesas Electronics Corporation
    Inventors: Takahiro Suzuki, Yasuo Notohara, Tsunehiro Endo, Yuji Mori
  • Voltage-sensed system and method for anti-islanding protection of grid-connected inverters
    Patent number: 7945413
    Abstract: A method is provided for preventing islanding of a power source connected to an electric AC grid via an interface. The method senses an output voltage waveform of the interface, controls an output current waveform of the interface to track a reference current waveform having a mathematical relationship with the sensed output voltage waveform, and discontinues the output current waveform when the output voltage waveform is sensed to be outside a predetermined waveform range.
    Type: Grant
    Filed: September 4, 2007
    Date of Patent: May 17, 2011
    Assignee: SolarBridge Technologies, Inc.
    Inventor: Philip T. Krein
  • Method and apparatus for stabilizing voltage of intermediate circuit of frequency converter
    Patent number: 7944087
    Abstract: A method and an apparatus for damping voltage oscillation of a voltage intermediate circuit of a frequency converter, the frequency converter comprising a half controlled rectifier bridge coupled to a supply network. The method comprises determining magnitude (Uc) of voltage of the voltage intermediate circuit, determining magnitude (Uin) of rectified voltage of the supply network, forming a derivative of a difference (Uin?Uc) between the rectified voltage of the supply network and the voltage of the voltage intermediate circuit, delaying firing of controllable components of the rectifier bridge on the basis of the formed derivative.
    Type: Grant
    Filed: August 18, 2008
    Date of Patent: May 17, 2011
    Assignee: ABB OY
    Inventor: Markku Talja
  • Static VAR corrector
    Patent number: 7940029
    Abstract: A system for providing reactive power compensation to a utility power network includes a switch coupled to the utility power network, and a capacitor coupled with the switch for providing a controlled amount of reactive current based on conditions of the utility power network. The system also includes a switchable power dissipation device coupled in series to the capacitor and configured to provide a preselected amount of impedance to the reactive current for a predetermined duration when a line voltage on the utility power network drops below a threshold.
    Type: Grant
    Filed: July 2, 2008
    Date of Patent: May 10, 2011
    Assignee: American Superconductor Corporation
    Inventor: Lynn Johnson
  • DC-DC converter with current overload protection circuit and method
    Patent number: 7940030
    Abstract: A DC-DC converter including: a switch, having a control terminal receiving a control signal, and a conduction terminal supplying a current; a load, coupled to the conduction terminal of the switch and selectively receiving the current; a control circuit, receiving a clock signal and generating the control signal in synchronism with the clock signal; an overcurrent sensor, coupled to the switch so as to monitor an electrical quantity correlated to the current and to output a protection signal in presence of overcurrent; moreover including overcurrent-protection circuitry, receiving the protection signal and the clock signal and generating a disabling signal for the control circuit if delay between an overcurrent detection and the clock signal is shorter than a detection time.
    Type: Grant
    Filed: July 29, 2008
    Date of Patent: May 10, 2011
    Assignee: STMicroelectronics S.r.l.
    Inventors: Eliana Cannella, Filippo Marino
  • Multi-voltage power supply
    Patent number: 7940538
    Abstract: A multi-voltage power supply includes a transformer, a first output circuit to generate a first output voltage using a voltage transferred to a secondary winding of the transformer, and a first output voltage controller to control a voltage supplied to the primary winding of the transformer according to the first output voltage. The multi-voltage power supply includes second through Nth output circuits to generate second through Nth output voltages using the voltage transferred to the secondary winding of the transformer, and second through Nth output voltage controllers performing control in order to linearly output the second through Nth output voltages by feeding back the second through Nth output voltages.
    Type: Grant
    Filed: January 20, 2010
    Date of Patent: May 10, 2011
    Assignee: SAMSUNG Electronics Co., Ltd.
    Inventor: Bong-hwan Kwon
  • Step-down voltage converter
    Patent number: 7940533
    Abstract: A step-down voltage converter (100) for generating an output voltage (VOUT) from an input voltage (VIN) is provided. The converter (100) includes a switch (111) having a first terminal (112) and a second terminal (114), wherein the second terminal (114) is electrically coupled with the output voltage (VOUT). Also included is a rectifier (117) having a first terminal (118) and a second terminal (120), wherein the second terminal (120) is electrically coupled with the output voltage (VOUT). A first inductor (124) electrically couples the first terminal (112) of the switch (111) with the input voltage (VIN). A second inductor (126) magnetically coupled with the first inductor (124) electrically couples the first terminal (118) of the rectifier (117) with a voltage reference (128). A switch controller (110) coupled with the output voltage (VOUT) is configured to control the switch (111).
    Type: Grant
    Filed: July 26, 2005
    Date of Patent: May 10, 2011
    Assignee: Micro Motion, Inc.
    Inventors: William M. Mansfield, Stig Lindemann
  • Switching power source
    Patent number: 7936152
    Abstract: An error voltage Verr, as amplified by an amplifier, and an input voltage Vin, are multiplied together by a multiplier to generate a first threshold value signal Vth1, which is in phase with and similar in waveform to the input voltage Vin, and proportional in amplitude to the error voltage Verr. A second threshold value signal Vth2 is generated from the first threshold value signal Vth1 by a series circuit of a diode and a resistor. The power factor is increased by on/off-control of a switching element via a drive circuit, so that a current detection signal Vi, which is detected by a resistor and corresponds to an input current, falls between the two threshold value signals Vth1 and Vth2. Since the off time is not fixed, the noise spectrum is spread and increase of the switching frequency is suppressed. Noise reduction thus can be attained.
    Type: Grant
    Filed: July 7, 2008
    Date of Patent: May 3, 2011
    Assignee: Fuji Electric Systems Co., Ltd.
    Inventor: Hideo Shimizu
  • Method and apparatus for synchronous buck with active negative current modulation
    Patent number: 7928713
    Abstract: A circuit is disclosed that includes a buck voltage regulator electrically coupled to an active current modulator. The active current modulator is operable to detect a negative current in the low-side switch of the buck voltage regulator circuit during a light mode operation. Whenever the negative current is detected, the active negative current modulator causes the low-side switch to stay ON in a linear mode and limits the negative current to a predetermined current level.
    Type: Grant
    Filed: March 28, 2008
    Date of Patent: April 19, 2011
    Assignee: Monolithic Power Systems, Inc.
    Inventor: James H. Nguyen
  • Voltage detection device
    Patent number: 7928776
    Abstract: An voltage detection device includes a comparator circuit comprising a first input terminal connected to a system power supply, a second input terminal connected to a standby power supply, an output terminal capable of outputting a control voltage according to comparison result; an indicator circuit; and a switch circuit connected between the standby power supply and the indicator circuit, comprising a control terminal to receive the control voltage from the comparator circuit thereby to control the standby power supply supplied to the indicator circuit or not; a power state terminal of the computer connected to a node between the standby power supply and the indicator circuit, wherein the power state terminal is at a low level when the computer is turned off. The voltage detection device can ensure that all the power supplies provide power to the computer components normally.
    Type: Grant
    Filed: August 21, 2008
    Date of Patent: April 19, 2011
    Assignees: Hong Fu Jin Precision Industry (ShenZhen) Co., Ltd., Hon Hai Precision Industry Co., Ltd.
    Inventors: Ning Wang, Cheng Qian, Yong-Xing You
  • Phase control method and phase control device
    Patent number: 7923666
    Abstract: A selectable operation amount is set as a threshold value according to an input operation amount, where if a determination value obtained by adding the input operation amount and an integrated operation amount or an output error accumulated value is greater than or equal to the threshold value, the threshold value is selected as the output operation amount, and if the determination value is not greater than or equal to the threshold value, a selectable output operation amount close to the threshold value is selected, and the ON/OFF control is performed with the selected output operation amount, while the selected output operation amount is subtracted from the determination value to correct the integrated operation amount, so that the input operation can be substantially output even if it takes an operation amount other than the selectable operation amount values.
    Type: Grant
    Filed: April 7, 2008
    Date of Patent: April 12, 2011
    Assignee: Omron Corporation
    Inventors: Fumimasa Katayama, Takeshi Kishimoto, Takaaki Yamada
  • Methods and apparatus for controlling a digital power supply
    Patent number: 7919958
    Abstract: Methods and apparatus for controlling a digital power supply are disclosed. An example method includes storing a first set of coefficients for controlling a digital power supply in a memory of the digital power supply, associating the first set of coefficients with a first set of characteristics of an input voltage for the digital power supply, storing a second set of coefficients for controlling the digital power supply in the memory of the digital power supply, associating the second set of coefficients with a second set of characteristics of the input voltage, receiving a first voltage from a voltage source at the digital power supply, determining that the first voltage has the first set of characteristics, and, in response to determining that the first voltage has the first set of characteristics, applying the first set of coefficients to the digital power supply.
    Type: Grant
    Filed: December 31, 2007
    Date of Patent: April 5, 2011
    Assignee: Texas Instruments Incorporated
    Inventors: Eric Gregory Oettinger, Mark David Hagen
  • Start-up circuit and method for high voltage power distribution circuit
    Patent number: 7919956
    Abstract: A start-up circuit for a high voltage power distribution circuit includes a transistor, a current source which generates ramped current, an operational amplifier which is connected between the current source and the transistor and controls the transistor, a capacitor which is fed the generated ramped current from the current source and is charged by the generated ramped current, the capacitor being connected to the non-inverting input of the operational amplifier, and a feedback capacitor connected from the transistor output to the non-inverting input of the operational amplifier, which is fed the generated ramped current from the capacitor and is discharged. The transistor is fully enabled when the feedback capacitor is fully discharged.
    Type: Grant
    Filed: March 10, 2010
    Date of Patent: April 5, 2011
    Assignee: International Business Machines Corporation
    Inventor: Robert B. Schlak
  • Semiconductor integrated circuit
    Patent number: 7915952
    Abstract: In a semiconductor integrated circuit, a switching circuit controls the capacity of a capacitor unit based on a control signal from a control circuit and separates a resonant frequency determined by first inductance, second inductance, and the capacity of the capacitor unit from the band area of the signal handled by an A/D converter.
    Type: Grant
    Filed: July 3, 2008
    Date of Patent: March 29, 2011
    Assignee: Ricoh Company, Ltd.
    Inventor: Hideaki Murakami