Switched (e.g., Switching Regulators) Patents (Class 323/351)
  • Patent number: 7492139
    Abstract: A method is disclosed for converting DC power from a first voltage level on an input to a different voltage level on an output for delivery to a load. The method includes switching current in a switching operation from the input to the output through an inductive element and measuring the voltage/current parameters on the input and output. A control algorithm is then utilized to determine control parameters necessary to make a control move to effect the switching operation, the control algorithm utilizing as inputs the measured voltage/current parameters. A digital control system controls the switching operation, which digital control system is operable to be controlled by the control algorithm. Configuration data is received on a serial data bus for configuring the control algorithm. Thereafter, the operation of the control algorithm is modified in response to receiving the configuration information.
    Type: Grant
    Filed: May 9, 2006
    Date of Patent: February 17, 2009
    Assignee: Silicon Labs CP, Inc.
    Inventors: Donald E. Alfano, Paul Highley, Kenneth W. Fernald
  • Patent number: 7492142
    Abstract: A DC chopper features a setting device, which sets a required current value signal being dependent on a filtered input voltage such that an oscillation of the input filter device and an oscillation of the current are phase-opposed. The DC chopper may further have a control device, which, depending on the input voltage, supplies a control signal and adds the control signal to the actual current value signal supplied to form a controlled actual current value signal. The DC chopper may optionally have a disconnection device, which receives a switch-off signal on the input side and, depending on the switch-off signal received, supplies a ramp disconnection signal, and an adding node which adds the actual current value signal to the ramp disconnection signal to form an elevated actual current value signal.
    Type: Grant
    Filed: October 20, 2006
    Date of Patent: February 17, 2009
    Assignee: Siemens Aktiengesellschaft
    Inventor: Martin Götzenberger
  • Publication number: 20080315858
    Abstract: A switch mode power supply apparatus includes a transformer, a main switching device to adjust a power supply supplied to a primary coil of the transformer, an active clamping circuit to suppress a voltage stress of the main switching device, and a control circuit to control a clamping operation of the active clamping circuit when the switch mode power supply apparatus is in a standby mode. Therewith, it is possible to significantly reduce power consumption of the switch mode power supply apparatus in the standby mode and improve efficiency of the switch mode power supply apparatus.
    Type: Application
    Filed: January 9, 2008
    Publication date: December 25, 2008
    Applicant: Samsung Electronics Co.
    Inventors: Hyung-won HONG, Joe-hoon Jung
  • Publication number: 20080315859
    Abstract: A switchgear cell is disclosed having a first energy store and a second energy store connected in series therewith, having a first, second, third and fourth power semiconductor switch, which are connected in series, wherein the first, second, third and fourth power semiconductor switch are in each case one drivable bidirectional power semiconductor switch with a controlled unidirectional current-conducting direction. The first power semiconductor switch is connected to the first energy store, and the fourth power semiconductor switch is connected to the second energy store. A third energy store is connected to the junction between the first and the second power semiconductor switch and the junction between the third and the fourth power semiconductor switch.
    Type: Application
    Filed: July 31, 2008
    Publication date: December 25, 2008
    Applicant: ABB Research Ltd
    Inventors: Srinivas Ponnaluri, Christoph Haderli
  • Publication number: 20080309313
    Abstract: Handshaking circuits are provided in a communications cable and in a device operable to be mated with the communications cable. Before a device can utilize the power supply signal of such a communications channel, the two handshaking circuits must sufficiently identify one another over a power supply signal with a decreased voltage. The decreased voltage allows for a cable plug to be provided with a safe, protected power that cannot cause harm to a human. The decreased voltage also reduces the chance that a device can receive a primary power supply signal from the cable before the device sufficiently identifies itself. Accordingly, a laptop may be connected to a portable music player, but the voltage of the power supply signal provided by the laptop to the cable may be decreased on-cable until the handshaking circuit of the portable music player sufficiently performs a handshaking operation with a on-cable handshaking circuit.
    Type: Application
    Filed: June 13, 2008
    Publication date: December 18, 2008
    Applicant: Apple Inc.
    Inventors: Doug Farrar, Lawrence Heyl, Brian Sander
  • Publication number: 20080284408
    Abstract: A system involves LED strings and programmable current source circuits (CSC). An LED current flows through each LED string. Each LED current is controlled by an associated programmable CSC. In one embodiment, the CSCs form a chain. A first CSC uses a reference current for calibration, and thereafter supplies the reference current to the next CSC. When the next CSC detects the reference current, it uses the reference current for calibration. CSCs are calibrated one by one down the chain. In a second embodiment, each CSC can receive the reference current from a common conductor. If the common conductor is detected to be available, then the CSC uses the reference current for calibration. When the conductor is in use, the other CSCs detect the conductor as unavailable and do not attempt to self-calibrate. The CSCs use the reference current one by one, but in an order that changes over time.
    Type: Application
    Filed: June 29, 2007
    Publication date: November 20, 2008
    Inventors: David J. Kunst, Steven Huynh, Richard L. Gray
  • Publication number: 20080278139
    Abstract: There is provided a sleep current adjusting circuit of a system on chip including: a regulator supplying a turn-on voltage and a normal current when a mode selection signal is a normal mode signal, and a turn-off voltage when the mode selection signal is a sleep mode signal; a switching device turned on by the turn-on voltage of the regulator to supply the normal current from the regulator to a main circuit part and a sleep operation circuit part, respectively, and turned off by the turn-off voltage of the regulator to block the normal current from being supplied to the main circuit part and supply the sleep current to the sleep operation circuit part; and a current limit device limiting an operating current flowing in response to the operating voltage and supplying the sleep current to the sleep operation circuit part.
    Type: Application
    Filed: April 18, 2008
    Publication date: November 13, 2008
    Applicant: SAMSUNG ELECTRO-MECHANICS., LTD.
    Inventors: Yong Il Kwon, Myeung Su Kim, Joon Hyung Lim, Koon Shik Cho, Tah Joon Park
  • Patent number: 7449874
    Abstract: A voltage regulator system is disclosed for providing a regulated voltage supply. The voltage regulator system includes a power supply input node for receiving a power supply input voltage, a regulated voltage output node for providing a regulated output voltage, and a feedback circuit coupled to the regulated output voltage node and to a voltage regulator input node wherein a non-zero voltage is provided by the voltage regulator input node.
    Type: Grant
    Filed: October 11, 2005
    Date of Patent: November 11, 2008
    Assignee: Analog Devices, Inc.
    Inventor: Anatol Seliverstov
  • Patent number: 7451025
    Abstract: A power control circuit is provided in a vehicle control ECU mounted in a vehicle. The control circuit, when making a shift to a test mode by a test mode circuit, closes a relay to supply a power voltage from a battery to a power line in the similar manner as an ignition main switch is turned on. A logic circuit section of the test mode circuit is reset by an OR logic of a set level of a test terminal and a level of the power line.
    Type: Grant
    Filed: November 29, 2005
    Date of Patent: November 11, 2008
    Assignee: Denso Corporation
    Inventors: Akio Kojima, Nobutomo Takagi
  • Publication number: 20080272099
    Abstract: A system and method for operating an inverted-based power source includes a power input configured to receive alternating current (AC) power and a rectifier configured to convert the AC power to direct current (DC) power. The inverter-based power source also includes an inverter configured to receive the DC power from the rectifier and convert the DC power to AC power and a controller configured to generate switching signals according to a pattern of offsets from a regular half period and communicate the switching signals to the inverter or rectifier control operation of the inverter or rectifier.
    Type: Application
    Filed: May 4, 2007
    Publication date: November 6, 2008
    Inventors: Bernard J. Vogel, Michael D. Madsen, Todd G. Batzler
  • Publication number: 20080265863
    Abstract: A reference current circuit includes a differential amplifier amplifying a difference in potential between a reference voltage and a first node and outputting the amplified potential difference to a second node, and adjusting transistors connected between a supply voltage and the first node. The reference current circuit further includes switches provided correspondingly to the adjusting transistors to apply a voltage of the second node to control electrodes of the adjusting transistors in response to control signals that are respectively input to the switches. The reference current circuit further includes a resistance connected between the first node and a common potential, and an output transistor having its conduction state responsive to the voltage of the second node for controlling a current supplied from the supply voltage to a load.
    Type: Application
    Filed: April 11, 2008
    Publication date: October 30, 2008
    Applicant: OKI ELECTRIC INDUSTRY CO., LTD.
    Inventors: Danya SUGAI, Naoaki SUGIMURA
  • Publication number: 20080258702
    Abstract: An output circuit in accordance with one embodiment of the present invention includes: an input terminal for receiving an input signal; an output transistor connected between a first power supply and an output terminal; a current control circuit connected to the input terminal and the output transistor for controlling current outflow and inflow for the gate of the output transistor based on the input signal; a voltage generating circuit connected to the first power supply; and a switch circuit coupled between the gate of the output transistor and the voltage generating circuit, the switch circuit having alternatively an on state and an off state thereof in response to the input signal; wherein the switch circuit becomes the off state when the potential difference between the gate of the output transistor and the first power supply becomes equal to or below a predetermine value regardless of the voltage level of the input signal.
    Type: Application
    Filed: April 16, 2008
    Publication date: October 23, 2008
    Applicant: NEC ELECTRONICS CORPORATION
    Inventors: Jiro KANAMARU, Toshiaki AKIOKA
  • Patent number: 7429850
    Abstract: A circuit to generate a bias voltage, the circuit including an inductor, a first capacitor associated with the second inductor node, a diode, and a second capacitor being associated with ground, the second capacitor including a second capacitor node, a switch configured to connect the inductor current to ground when closed. The first capacitor and the second capacitor become charged via the trigger resistor by the inductor current until the trigger node reaches the trigger threshold and the trigger closes the switch when the trigger threshold is reached. The inductor is drained when the switch is opened and, when the inductor current reaches zero, an inductor voltage provides a negative voltage step at the trigger node via the first capacitor and when the negative voltage step is provided to the trigger node, the trigger directs the switch to close.
    Type: Grant
    Filed: March 31, 2008
    Date of Patent: September 30, 2008
    Assignee: International Business Machines Corporation
    Inventor: Fritz Wochele
  • Publication number: 20080217095
    Abstract: In a state where an abnormality of a boosting circuit is detected by monitoring a boosted voltage outputted from the boosting circuit, motor relays are turned to an off state when the boosted voltage outputted from the boosting circuit becomes less than a predetermined threshold value due to an action, such as the stopping of a supply of power source voltage to the boosting circuit. Therefore, there can be limited welding of the motor relays caused by an electric arc, which is generated when contacts of the motor relays, are separated.
    Type: Application
    Filed: February 18, 2005
    Publication date: September 11, 2008
    Applicant: Denso Corporation
    Inventor: Hiroaki Ono
  • Publication number: 20080218149
    Abstract: The present invention is intended to minimize an amount of charge that flows from a step-up circuit into an external input voltage terminal when the power supply is turned off. A display device includes a display panel and a drive circuit that drives pixels included in the display panel. The drive circuit includes a power circuit to which a voltage Vcc is fed. The power circuit includes: a first step-up circuit that generates a voltage DDVDH which is higher than the voltage Vcc; a means 1 that when the first step-up circuit is de-energized, connects the voltage DDVDH output terminal of the first step-up circuit to a reference voltage terminal via a resistive element during a first period; and a means 2 that connects the voltage DDVDH output terminal of the first step-up circuit to an input terminal, to which the voltage Vcc is fed, during a second period succeeding the first period.
    Type: Application
    Filed: October 16, 2007
    Publication date: September 11, 2008
    Inventors: Yoshinori Aoki, Mitsuru Goto, Yoshihiro Kotani
  • Publication number: 20080203995
    Abstract: In a cordless power tool system, a battery pack which may removably attachable to a cordless power tool and to a charger may include at least one battery cell and a power limiting device. The power limiting device may be arranged in series with the at least one battery cell for limiting power output of the battery pack based on the component that is connected to the pack. Current and hence power out of the battery pack may be controlled as a function of total internal impedance in the battery pack, which may be adjusted depending on the component that is connected to the pack.
    Type: Application
    Filed: April 28, 2008
    Publication date: August 28, 2008
    Inventors: David A. Carrier, Bhanuprasad V. Gorti, Danh Thanh Trinh, R. Roby Bailey, Andrew E. Seman, Daniele C. Brotto, Fred S. Watts
  • Patent number: 7408334
    Abstract: A DC converter with a halt mode setting is disclosed for preventing the occurrence of over-current while alleviating the increase in the size of circuits, along with a method for setting up such a halt mode. The DC converter includes a semiconductor switch, a clock generator for outputting a clock signal to a gate of the semiconductor switch to be utilized for controlling an on/off time of the semiconductor switch such that a predetermined power is output from the generator, and a drive circuit for switching the semiconductor switch to the continuous-on state according to a halt mode setting requirement regardless of the clock signal, when the semiconductor switch, normally repeating on/off operations responsive to the clock signal, is in its off-state.
    Type: Grant
    Filed: February 13, 2007
    Date of Patent: August 5, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Katsuhiko Manabe, Tomonari Katoh, Minoru Sugiyama, Makoto Matsushima, Tadayoshi Ueda
  • Patent number: 7402988
    Abstract: A switching regulator includes a reference voltage generator and a switching-regulating module. The reference voltage generator receives a digital control signal and generates a reference voltage according to the digital control signal. The switching-regulating module is connected to the reference voltage generator and generates an output voltage according to the reference voltage. The value of the digital control signal is gradually increased to make the reference voltage being gradually increased at the initial stage of the activation of the switching regulator.
    Type: Grant
    Filed: February 24, 2006
    Date of Patent: July 22, 2008
    Assignee: Realtek Semiconductor Corp.
    Inventors: Pao-Cheng Chiu, Chieh-Min Feng, Ming-Han Lee
  • Patent number: 7403399
    Abstract: The invention under consideration refers to a circuit arrangement for a switch-mode power supply, wherein the switch-mode power supply has a primary side, which can be connected to a supply voltage, and a secondary side, which can be connected to a consumer, and wherein the circuit arrangement comprises a primary-sided switch, a control circuit for controlling the primary-sided switch and additional active primary-sided components. Furthermore, the invention under consideration also refers to a switch-mode power supply with an active primary-sided circuit arrangement of that type.
    Type: Grant
    Filed: March 30, 2006
    Date of Patent: July 22, 2008
    Assignee: FRIWO Mobile Power GmbH
    Inventors: Stefan Morbe, Michael Bothe
  • Publication number: 20080170153
    Abstract: A signal processor for reducing power consumption. The signal processor includes a signal processing circuit and a first regulator connected to the signal processing circuit. The first regulator receives an external regulated voltage from an external regulator connected to the signal processor and generates an internal regulated voltage that is in accordance with an output level of a CCD image sensor. The signal processing circuit operates with the internal regulated voltage and performs a predetermined signal processing on an image signal generated by the CCD image sensor.
    Type: Application
    Filed: March 4, 2008
    Publication date: July 17, 2008
    Applicant: SANYO ELECTRIC CO., LTD.
    Inventors: Tohru Watanabe, Takashi Tanimoto, Tatsuya Takahashi
  • Patent number: 7394234
    Abstract: A power-supply circuit for supplying voltage to a load while freely selecting positive voltage and negative voltage using a single power supply has a power supply that generates power-supply voltage, an inverted outputting circuit having a positive voltage terminal for outputting positive voltage based on the power-supply voltage and a negative voltage terminal for outputting negative voltage generated based on the power-supply voltage and having different polarity from the positive voltage and outputting the positive and negative voltage while keeping the same direction in terms of directions of electric current flowing between the positive voltage terminal and the outside and of electric current flowing between the negative voltage terminal and the outside and a step-down output circuit for supplying predetermined voltage to the load by connecting the positive voltage terminal and the negative voltage terminal to the load while switching them with a predetermined duty ratio.
    Type: Grant
    Filed: March 23, 2006
    Date of Patent: July 1, 2008
    Assignee: Advantest Corporation
    Inventor: Satoshi Kodera
  • Publication number: 20080150512
    Abstract: A USB electronic device with a power source loaded therein, which is connected to another USB electronic device via a USB connector, comprises a voltage detection unit that detects a voltage at an identification pin of the USB connector, a power supply control unit that controls connection/disconnection between a power supply pin of the USB connector and the power source based upon a change in voltage at the identification pin detected by the voltage detection unit and an allow/disallow control unit that executes control to allow/disallow detection of the voltage change at the identification pin.
    Type: Application
    Filed: December 17, 2007
    Publication date: June 26, 2008
    Applicant: NIKON CORPORATION
    Inventor: Takeshi Kawano
  • Patent number: 7391200
    Abstract: An integrated circuit device for delivering power to a load includes a P-MOS power transistor, an N-MOS bypass transistor and a gate driver circuit. The P-MOS power transistor is coupled between a supply voltage node and a power output node of the integrated circuit device, and the N-MOS bypass transistor is coupled between the power output node and a reference node of the integrated circuit device. The gate driver circuit responds to a pulse-width-modulated (PWM) control signal by outputting an active-low drive-enable signal to a gate terminal of the P-MOS power transistor and an active-high bypass-enable signal to a gate terminal of the N-MOS bypass transistor during respective, non-overlapping intervals.
    Type: Grant
    Filed: February 2, 2007
    Date of Patent: June 24, 2008
    Assignee: NetLogic Microsystems, Inc.
    Inventors: Sandeep Khanna, Varadarajan Srinivasan
  • Publication number: 20080122422
    Abstract: A method and apparatus to implement parallel current mode control that is suitable for digital and analog implementation. A duty cycle algorithm is composed of a voltage term and a parallel current term which depends on the inductor current change between the inductor current value at the beginning of a switching cycle and the reference inductor current value at the end of that switching cycle. Parallel current mode control can be applied to all DC-DC converters, including both non-isolated and isolated topologies. It can also be applied to AC-DC converters with power factor correction.
    Type: Application
    Filed: December 5, 2007
    Publication date: May 29, 2008
    Applicant: IWATT INC.
    Inventors: Wanfeng Zhang, Yan-Fei Liu, Bin Wu
  • Publication number: 20080111535
    Abstract: The present invention provides a separate type converter. The separate type converter includes a power control module having a power control circuit generating a first control signal, and a power stage module having a power stage circuit coupled to the power control circuit for receiving the first control signal and an input voltage, and generating an output voltage, in which the power control module and the power stage module are separate from each other in an assembling structure.
    Type: Application
    Filed: July 2, 2007
    Publication date: May 15, 2008
    Applicant: DELTA ELECTRONICS, INC.
    Inventors: Jen-Ta SU, Hsin-Liang Lin, Chung-Cheng Chang, Pei-Sheng Liao
  • Publication number: 20080111534
    Abstract: A voltage regulator architecture for an integrated circuit is described. An apparatus may comprise a power switch array having multiple pass transistors, a voltage regulator array having multiple voltage regulators each coupled to a subset of the pass transistors, a subsystem circuit array having multiple subsystem circuits each coupled to a subset of the pass transistors, and a power management control unit coupled to the pass transistors and the voltage regulators. The power management control unit may be arranged to control the pass transistors and voltage regulators to provide different amounts of power to the subsystem circuits. Other embodiments are described and claimed.
    Type: Application
    Filed: November 9, 2006
    Publication date: May 15, 2008
    Inventor: Krishnan Ravichandran
  • Patent number: 7372500
    Abstract: A signal processor for reducing power consumption. The signal processor includes a signal processing circuit and a first regulator connected to the signal processing circuit. The first regulator receives an external regulated voltage from an external regulator connected to the signal processor and generates an internal regulated voltage that is in accordance with an output level of a CCD image sensor. The signal processing circuit operates with the internal regulated voltage and performs a predetermined signal processing on an image signal generated by the CCD image sensor.
    Type: Grant
    Filed: July 30, 2002
    Date of Patent: May 13, 2008
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tohru Watanabe, Takashi Tanimoto, Tatsuya Takahashi
  • Publication number: 20080054872
    Abstract: An integrated circuit device includes: an internal circuit disposed on an inside area of the integrated circuit device; and at least one regulator circuit that generates a regulation voltage formed by stepping down a power supply voltage provided from outside, wherein an output terminal of the regulator circuit is connected to a first pad that is an external terminal of the integrated circuit device and a power supply line of the internal circuit, and the regulator circuit controls the state of the output terminal based on a plurality of control signals inputted respectively to a plurality of control terminals.
    Type: Application
    Filed: August 29, 2007
    Publication date: March 6, 2008
    Applicant: SEIKO EPSON CORPORATION
    Inventor: Shinichiro KOBAYASHI
  • Patent number: 7332879
    Abstract: A control device, which controls a power-converting module that is coupled to a light-emitting component, includes a duration detecting unit and a control signal generator. The duration detecting unit compares the duration of a predetermined logic state of a pulsating input dim control signal with a reference time period. The control signal generator is enabled by the duration detecting unit so as to generate a control signal that enables the power-converting module to generate a drive voltage for driving the light-emitting component when the duration of the predetermined logic state is not longer than the reference time period. The duration detecting unit disables the control signal generator to disable the power-converting module when the duration of the predetermined logic state is longer than the reference time period.
    Type: Grant
    Filed: August 16, 2004
    Date of Patent: February 19, 2008
    Assignee: Richtek Technology Corp.
    Inventors: Nien-Hui Kung, Yiu-I Lin, Der-Jiunn Wang, Chao-Hsuan Chuang, Jien-Sheng Chen, Shui-Mu Lin, Wei-Hsin Wei
  • Publication number: 20080036443
    Abstract: A synchronous rectification switching regulator, and a control circuit and a control method for controlling the synchronous rectification switching regulator. The regulator includes an output terminal, a first switching device, an inductor, a second switching device for synchronous rectification, a control circuit unit to control switching of the first switching device and cause the second switching device to perform switching opposite to that of the first switching device, and a reverse current detection circuit unit to detect a generation or an indication of a reverse current flowing from the output terminal to the second switching device and make the control circuit unit turn off the second switching device when a generation or an indication of the reverse current is detected. The reverse current detection circuit unit stops detecting a generation or an indication of the reverse current while the second switching device is turned off by the control circuit unit.
    Type: Application
    Filed: August 6, 2007
    Publication date: February 14, 2008
    Inventor: Shinichi Kojima
  • Patent number: 7315153
    Abstract: A switching power supply circuit in which a series circuit comprising a resistive element and a capacitive element is provided in a parallel configuration with an inductor which supplies a load current to a load circuit, a voltage comparator having first and second threshold voltages discriminates a voltage obtained from a mutual connecting point of the series circuit therefrom and controls a switch element for supplying a current to the inductor, thereby varying the current supplied to the inductor in accordance with a variation in the load current is combined with a series power supply circuit which shares the load current of the load circuit.
    Type: Grant
    Filed: June 3, 2004
    Date of Patent: January 1, 2008
    Assignee: Renesas Technology Corporation
    Inventors: Tomohiro Tazawa, Shinichi Yoshida
  • Patent number: 7315159
    Abstract: An object of this invention is to finely set the voltage at high speed without decreasing the efficiency. In a power supply for switching operation including a switching circuit, an output circuit, a control table which stores data on the ON and OFF periods of the switching circuit in correspondence with a set voltage, an arithmetic processing unit which performs reading operation from the control table and PWM operation, and a digital control unit which controls the switching circuit by outputting a PWM signal, feedback control based on the output voltage is performed in a case where the output voltage is not changed. When changing the output voltage, the feedback control is switched over to control based on data in the control table to change the output voltage at high speed.
    Type: Grant
    Filed: October 17, 2006
    Date of Patent: January 1, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventor: Masayuki Nagai
  • Publication number: 20070285077
    Abstract: A DC-DC converter for preventing through current from causing erroneous operation of an ideal diode. A first transistor for receiving input voltage is connected to an ideal diode, which includes a second transistor and a comparator for detecting current flowing through the second transistor and generating a detection signal. A control circuit generates a switching signal for turning the first transistor on and off so as to keep the output voltage constant. A pulse generation circuit generates a pulse signal for turning off the second transistor before the first transistor is turned on and keeping the second transistor turned off for a predetermined period from when the first transistor is turned on. An erroneous operation prevention circuit generates a control signal for keeping the second transistor turned off from when the second transistor is turned off to when the first transistor is turned on.
    Type: Application
    Filed: April 23, 2007
    Publication date: December 13, 2007
    Inventor: Morihito Hasegawa
  • Patent number: 7307407
    Abstract: In a power supply apparatus, in a standby mode, control signals for controlling a first MOSFET of a power supply apparatus to be turned on and a second MOSFET to be turned off are supplied to the gates of the first and second MOSFETs from a control circuit, respectively. The emitter of a PNP transistor is connected to the gate of the second MOSFET through a diode of a switch circuit and the collector is connected to the ground. A power supply operation control signal is input to the base of the PNP transistor. When a power supply operation control signal in a Low state is input to the base in a standby mode, the emitter and the collector are connected to each other. Accordingly, the gate of the second MOSFET has a potential substantially the same as a ground potential and the second MOSFET is turned off irrespective of the control signal.
    Type: Grant
    Filed: January 19, 2007
    Date of Patent: December 11, 2007
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Koji Nishi, Soichi Watanabe, Takashi Kurokawa
  • Patent number: 7271573
    Abstract: A direct current to direct current converter includes first and second switches to output voltages on first and second output terminals in response to appropriate turn-on voltages at first and second control terminals. The first control terminal may selectively communicate with one of N>2 different voltages. The converter may include a first multi-level controller in communication with the first control terminal, the controller including N drivers to selectively apply the N>2 different voltages to the first control terminal.
    Type: Grant
    Filed: August 15, 2006
    Date of Patent: September 18, 2007
    Assignee: Marvell World Trade Ltd.
    Inventor: Sehat Sutardja
  • Patent number: 7265525
    Abstract: A voltage converter uses a component such as a JFET or four-terminal power MOSFET having no body diode and exhibiting no body diode conduction characteristic as a synchronous rectifier to reduce switching losses and body diode conduction losses and to support high frequency switching so that use of smaller components and higher current densities can be achieved. These effects are enhanced by a self-driven circuit utilizing positive feedback to enhance switching speed and reduce switching losses which increase with switching frequency.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: September 4, 2007
    Assignee: Virginia Tech Intellectual Properties, Inc.
    Inventors: Ming Xu, Julu Sun, Jinghai Zhou, Fred C. Lee
  • Patent number: 7265527
    Abstract: A self-oscillating DCM is disclosed comprising two inductors that charge and discharge 180 degrees out of phase such that the charging inductor is conducting an upward ramping current and the discharging inductor is conducting a downward ramping current. A load receives the upward and downward ramping currents, which combine to create a constant current. The current source that powers the DCM is current limited so as to output a maximum direct current of IIN. A relatively small capacitor is connected across the input terminals of the DCM and allows the inductors to ramp up to a peak current of 2*IIN. Since the current source only supplies the ramping current to one of the inductors at a time up to 2*IIN, and the average current conducted by each inductor is IIN, the current supplied by the current source is a constant IIN. However, since the inductors simultaneously supply two oppositely ramping currents to the load, the load current is a constant current equal to 2*IIN.
    Type: Grant
    Filed: October 12, 2006
    Date of Patent: September 4, 2007
    Assignee: Micrel, Inc.
    Inventor: Eberhard Haug
  • Patent number: 7259542
    Abstract: Disclosed are an apparatus and method for controlling a Direct Current (DC)/DC converter which controls energy flow between a first DC source and a second DC source to eliminate a high-frequency resonance. The apparatus for controlling the DC/DC converter includes a voltage controller, one or more subtractors, one or more fundamental component current controllers, a first coordinate transformer, a resonance current component extractor, a resonance frequency tracker, one or more resonance component current controllers, a second coordinate transformer, one or more adders and a Pulse Width Modulation (PWM) signal generation unit. The method implemented by the apparatus can effectively control any high-frequency resonance current components generated in the DC/DC converter.
    Type: Grant
    Filed: December 12, 2005
    Date of Patent: August 21, 2007
    Assignee: Hyundai Motor Company
    Inventor: Hong-Seok Song
  • Patent number: 7245465
    Abstract: A voltage regulator has an output circuit for producing from an input voltage a predetermined output voltage to be supplied to a load, an overcurrent protection circuit for preventing overcurrent in the output circuit, a memory for storing control information fed from outside, and an adjustment circuit for adjusting the level at which the overcurrent protection circuit detects overcurrent according to the control information read from the memory. With this configuration, it is possible to accurately detect overcurrent by canceling factors such as individual variations in the characteristics of the circuit components, the influence of stress occurring when the regulator IC is packaged, and fabrication-associated variations in the load.
    Type: Grant
    Filed: December 3, 2002
    Date of Patent: July 17, 2007
    Assignee: Rohm Co., Ltd.
    Inventor: Takahiro Hikita
  • Patent number: 7230405
    Abstract: A non-isolated power conversion system has an input stage and an output stage. A plurality of cascaded switching power converter stages are coupled between the input stage and the output stage. Each of the plurality of switching power converter stages has at least one switch that is activated in accordance with a duty cycle associated with a switching cycle. At least one energy storage device temporarily stores energy that is proportional to the duty cycle during the switching cycle for delivery to the output stage.
    Type: Grant
    Filed: October 26, 2004
    Date of Patent: June 12, 2007
    Assignee: Delta Electronics, Inc.
    Inventors: Yungtaek Jang, Milan Jovanović
  • Patent number: 7224153
    Abstract: A power regulator has an output for regulated power that is connected to supply power to a load. The load can have various electrical characteristics, including requiring a rapid transient response. The transient response amplitude for the power regulator is decreased by adding capacitance at the output, but that slows the response time of the power regulator by lowering the crossover frequency and the phase margin at the crossover frequency. An adjustable gain element imbedded in the feedback network provides an input to permit a builder or user of the power regulator to vary the effective value of impedance elements in the feedback network. The builder or user selectively connects an impedance to the input of the adjustable gain element to thereby adjust the frequency characteristics of the feedback network to thereby adjust output characteristics of the power regulator to compensate for the effects of capacitance added to the power regulator output.
    Type: Grant
    Filed: April 26, 2005
    Date of Patent: May 29, 2007
    Assignee: Texas Instruments Incorporated
    Inventors: Charles Allen DeVries, Jr., Joseph Gerard Renauer, Michael G. Amaro
  • Patent number: 7218088
    Abstract: There are provided a control circuit of a DC-DC converter of a synchronous rectification system which can realize rapid lowering of an output voltage with low power consumption at the stop of power supply, and a control method thereof. While a power supply stop signal is at low level, a control part controls an NMOS transistor according to the output signals of a comparator and a flip-flop circuit. While the power supply stop signal is at high level, the control part masks a reverse current detection signal and the output signal of the flip-flop circuit to control the NMOS transistor according to a detection signal of a comparator. When a choke coil current is reversely flowed and an output voltage is lowered to an output reference voltage corresponding to a reference voltage, the NMOS transistor is brought to the non-conductive state to regenerate the electric power to an input terminal.
    Type: Grant
    Filed: April 12, 2006
    Date of Patent: May 15, 2007
    Assignee: Fujitsu Limited
    Inventor: Hidenobu Ito
  • Patent number: 7209770
    Abstract: An integrated circuit for supplying power includes an IC chip having a rectangular shape and having a first edge and a second edge opposite the first edge, a switching regulator implemented on the IC chip and having a driver transistor whose ON time of switching is controlled to adjust an output voltage of the switching regulator, and a series regulator implemented on the IC chip, wherein the driver transistor of the switching regulator is positioned near the first edge, and the series regulator is positioned near the second edge.
    Type: Grant
    Filed: December 4, 2003
    Date of Patent: April 24, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Hideki Agari, Kohji Yoshii
  • Patent number: 7202643
    Abstract: A DC-to-DC power regulator circuit, such as a synchronous buck DC-to-DC converter circuit, having improved efficiency. A power stage is provided, having an input port for receiving a DC input voltage and having an output port for providing a regulated DC output voltage. The power stage includes a control FET transistor having a first terminal, a second terminal, and a gate, the first terminal being connected to the input port. An energy storage element has a first terminal connected to the control FET output terminal and a second terminal connected to the output port. A driven FET transistor has a first terminal connected to ground, a second terminal connected to the first terminal of the energy storage element, and a gate. A driver circuit has an input adapted to receive a control signal, and provides first driver signal to the control FET gate and a second driver output signal to the driven FET gate.
    Type: Grant
    Filed: June 27, 2005
    Date of Patent: April 10, 2007
    Assignee: Texas Instruments Incorporated
    Inventor: Rais K. Miftakhutdinov
  • Patent number: 7199560
    Abstract: Pulse width modulation of the connection of a load output terminal to a power supply terminal is effected. In response to a first level of the pulse width modulated signal, the load is disconnected from the power supply terminal, steady-state load voltage is preserved on a capacitor connected between a load output terminal and a power supply terminal, and steady-state load current information is held on a capacitor within the feedback loop. In response to a second level of the pulse width modulated signal, the load is reconnected to the power supply terminal, and load voltage and current instantaneously resume at their correct steady-state values.
    Type: Grant
    Filed: November 5, 2004
    Date of Patent: April 3, 2007
    Assignee: Linear Technology Corporation
    Inventors: Eugene Lau Cheung, Talbott Mead Houk
  • Patent number: 7193400
    Abstract: A DC converter with a halt mode setting is disclosed for preventing the occurrence of over-current while alleviating the increase in the size of circuits, along with a method for setting up such a halt mode. The DC converter includes a semiconductor switch, a clock generator for outputting a clock signal to a gate of the semiconductor switch to be utilized for controlling an on/off time of the semiconductor switch such that a predetermined power is output from the generator, and a drive circuit for switching the semiconductor switch to the continuous-on state according to a halt mode setting requirement regardless of the clock signal, when the semiconductor switch, normally repeating on/off operations responsive to the clock signal, is in its off-state.
    Type: Grant
    Filed: February 10, 2006
    Date of Patent: March 20, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Katsuhiko Manabe, Tomonari Katoh, Minoru Sugiyama, Makoto Matsushima, Tadayoshi Ueda
  • Patent number: 7183757
    Abstract: There is provided a switching power source capable of quickly responding to a change in output at high efficiency over a wide output voltage range. The power source includes an integrator, a comparator which compares an output from the integrator with a quantization reference value, and a sampling circuit which samples an output from the comparator in synchronism with a clock signal. The power source further includes a ?? modulator which quantizes an output from the integrator, outputs a quantized signal, and negative-feeds back the quantized signal to suppress the quantization error of the input signal. In the switching power source, a resistance value adjustment circuit changes the hysteresis width of the quantization reference value by changing the resistance value of the variable resistor of the comparator on the basis of a signal output from a detection circuit which detects at least one of an external control signal and the output voltage and load current of the switching power source.
    Type: Grant
    Filed: February 14, 2006
    Date of Patent: February 27, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventor: Masayuki Nagai
  • Patent number: 7176669
    Abstract: In a frequency modulation type switching regulator for producing an output voltage to a load, an error amplifier produces an error voltage indicative of a difference between the output voltage and a reference voltage. A switching device is turned on and off at a switching frequency corresponding to the error voltage. A voltage-frequency modulation circuit monitors an operation condition of the load. The modulation circuit generates a varying voltage, which varies around the error voltage, when the monitored operation condition is substantially unchanged. The switching frequency is switched to another frequency corresponding to the varying voltage, so that noise level may be reduced.
    Type: Grant
    Filed: February 8, 2005
    Date of Patent: February 13, 2007
    Assignee: Denso Corporation
    Inventor: Goro Ueda
  • Patent number: 7161342
    Abstract: A direct current to direct current converter includes first and second switches to output voltages on first and second output terminals in response to appropriate turn-on voltages at first and second control terminals. The first control terminal may selectively communicate with one of N>2 different voltages. The converter may include a first multi-level controller in communication with the first control terminal, the controller including N drivers to selectively apply the N>2 different voltages to the first control terminal.
    Type: Grant
    Filed: July 15, 2003
    Date of Patent: January 9, 2007
    Assignee: Marvell World Trade Ltd.
    Inventor: Sehat Sutardja
  • Patent number: 7148673
    Abstract: A direct current to direct current converter includes first and second switches to output voltages on first and second output terminals in response to appropriate turn-on voltages at first and second control terminals. The first control terminal may selectively communicate with one of N>2 different voltages. The converter may include a first multi-level controller in communication with the first control terminal, the controller including N drivers to selectively apply the N>2 different voltages to the first control terminal.
    Type: Grant
    Filed: May 16, 2005
    Date of Patent: December 12, 2006
    Assignee: Marvell World Trade Ltd.
    Inventor: Sehat Sutardja