Having Feedback Isolation (e.g., Optoisolator, Transformer Coupled, Etc.) Patents (Class 363/21.07)
  • Patent number: 8027174
    Abstract: An advantage of the present invention is to provide an adapter power supply which varies a link voltage of DC power serving an input power of a DC/DC converter according to variation of a load current estimated by measuring a secondary current using a lossless current measurement technique at a primary terminal of a transformer of the DC/DC converter and thus presuming a load current of an output power. An adapter power supply according to present invention may include an AC/DC converter converting a commercial AC power into a DC power; a DC/DC converter including a transformer composed of a primary terminal and a secondary terminal in order to output an output power by converting a link voltage of the DC power; and a controller presuming a load current of the output power through a primary current of the transformer and varying the link voltage of the DC power according to variation of the estimated load current.
    Type: Grant
    Filed: October 7, 2008
    Date of Patent: September 27, 2011
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Byoung Woo Ryu, Gun Woo Moon, Seong Wook Choi, Jong Sun Kim, Dong Seong Oh
  • Patent number: 8009447
    Abstract: An energy effective switching power supply apparatus and an energy effective method thereof. The energy effective switching power supply apparatus includes a power transforming part having first and second coils to induce a voltage to the second coil using interactions between the first and the second coils with respect to the input voltage, a power outputting part to output a sensing signal when it is determined that a first DC voltage output by rectifying and smoothing the voltage induced to the second coil is greater than or equal to a reference voltage level, and a switching controlling part to adjust a switching frequency of a switching device to interrupt a current flowing in the first coil of the power transforming part when the sensing signal is received. Accordingly, a switching loss is controlled and an energy loss is reduced.
    Type: Grant
    Filed: November 3, 2009
    Date of Patent: August 30, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Tae-kwon NA
  • Patent number: 8004863
    Abstract: In an embodiment, a circuit device includes a network interface responsive to a powered network to receive a power supply and data and includes an electrical isolation barrier adapted to define a non-isolated power domain and an isolated power domain. The circuit device further includes a first control circuit associated with the non-isolated power domain. The first control circuit is coupled to a primary winding of a transformer to control current flow via the primary winding. The circuit device also includes a second control circuit associated with the isolated power domain. The second control circuit is coupled to a secondary winding of the transformer and is adapted to detect a power error associated with the secondary winding. The second control circuit transfers a command across the electrical isolation barrier to the first control circuit to adjust a current at the primary winding in response to detecting the power error.
    Type: Grant
    Filed: December 26, 2007
    Date of Patent: August 23, 2011
    Assignee: Silicon Laboratories Inc.
    Inventors: Walter Stuart Schopfer, Richard Bruce Webb
  • Patent number: 7990739
    Abstract: A resonant power converter is provided and includes a capacitor, an inductive device, a first transistor, a second transistor, and a control circuit. The capacitor and the inductive device develop a resonant tank. The first transistor and the second transistor are coupled to switch the resonant tank. The control circuit generates a first signal and a second signal to control the first transistor and the second transistor respectively. Frequencies of the first signal and the second signal are changed for regulating output of the resonant power converter. The control circuit is further coupled to detect an input voltage of the resonant power converter. A pulse width of the second signal is modulated in response to change of the input voltage.
    Type: Grant
    Filed: August 24, 2009
    Date of Patent: August 2, 2011
    Assignee: System General Corporation
    Inventors: Ta-Yung Yang, Ying-Chieh Su, Tien-Chi Lin, Shih-Hung Hsieh
  • Patent number: 7973496
    Abstract: The present invention relates to a power supply device for supplying power to a load, preferably a LED, comprising a first circuitry (12) with an inverter unit (24) adapted to provide an AC voltage, preferably a rectangular voltage, and a resonant circuit (30) with a capacitance (32) and an inductance (34), a second circuitry (14) with a rectifier unit (42), a switch (64) and said load (60), said switch being adapted to switch said load on and off, a controller unit (16) adapted to control said switch (64) as to adjust the power provided to said load (60) without any measurement signal from said primary circuitry (12), and a transformer (18) with a primary side (20) and a secondary side (22), said primary side being connected to said first circuitry (12) and said secondary side (22) being connected to said second circuitry (14), preferably said rectifier, so that said first and second circuitries are galvanically isolated.
    Type: Grant
    Filed: August 29, 2007
    Date of Patent: July 5, 2011
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Christoph Loef, Matthias Wendt
  • Publication number: 20110026277
    Abstract: A driving circuit for an opto-coupler comprising a switched mode regulator configured to convert a first voltage to a second voltage, the switched mode regulator operable in accordance with a control signal (311) representative of the first voltage, and wherein the second voltage is used to drive the diode (304a) of the opto-coupler (304), in use.
    Type: Application
    Filed: July 28, 2010
    Publication date: February 3, 2011
    Applicant: NXP B.V.
    Inventor: Joan Wichard Strijker
  • Patent number: 7856566
    Abstract: An electronics product has a control unit responsive to a power-on remote control signal to enable DC power converters to supply power for normal operation of the product and to a microprocessor for responding to other remote control signals. The microprocessor controls the control unit to return to a standby mode of the product by disabling the DC power converters. The arrangement facilitates eliminating a conventional standby power supply and achieving a very low standby power consumption.
    Type: Grant
    Filed: November 29, 2006
    Date of Patent: December 21, 2010
    Assignee: Power Integrations, Inc.
    Inventor: Raymond K. Orr
  • Patent number: 7835163
    Abstract: This invention discloses a power converter with a secondary-side control, including an input circuit with one or more switches, an output circuit with an output end and a controller, and a transformer with a primary-side coil assembly connecting the switch(es) and a secondary-side coil assembly connecting the output circuit. The on/off state of the switch(es) is controlled by variations in voltage of primary-side coil assembly. The controller in the output circuit detects an output voltage and sends detected results to the primary-side coil assembly as a feedback for primary-side coil assembly to regulate the PWM or PFM action of the switch in a specific way to maintain voltage stability.
    Type: Grant
    Filed: March 6, 2008
    Date of Patent: November 16, 2010
    Inventor: Chung Fu Chou
  • Publication number: 20100277957
    Abstract: A power system having a power saving mechanism includes a voltage regulator, a power input module, and a switching signal generation unit. The voltage regulator performs a regulation operation on a first voltage for generating a second voltage. The power input module includes a transformer, a rectifying unit, a switch, and a switch control unit. The rectifying unit together with the transformer is put in use for converting an input voltage into the first voltage. The switch is employed to control a current flowing through the primary winding of the transformer. The switch control unit generates a control signal for controlling the switch according to a switching signal. The switching signal generation unit is utilized for generating the switching signal to disable the switch control unit during an energy transfer disable interval so as to decrease the first voltage from a first predetermined voltage to a second predetermined voltage.
    Type: Application
    Filed: July 30, 2009
    Publication date: November 4, 2010
    Inventors: Chin-Sheng Chueh, Po-Wen Wang, Chien-Kun Huang, Chia-Tse Yeh, Yung-Chun Lin, Jiun-Wei Tseng
  • Patent number: 7817445
    Abstract: A power supply for a computer includes a transformer, a rectifier, a pulse width modulation (PWM) controller, a relay, a power switch, and a battery. The PWM controller includes a voltage terminal and a pulse terminal. The relay includes a switch and an inductance coil. An alternating current (AC) power supply is connected to a primary inductance coil of the transformer via the rectifier. A secondary inductance coil of the transformer provides a standby voltage. A positive voltage terminal of the rectifier is connected to the pulse terminal of the PWM controller via the primary inductance coil of the transformer. The switch is connected between the positive voltage terminal of the rectifier and the voltage terminal of the PWM controller. The inductance coil and the power switch are connected in series between the battery and ground. The power switch is controlled by powering on or off the computer.
    Type: Grant
    Filed: December 29, 2007
    Date of Patent: October 19, 2010
    Assignees: Hong Fu Jin Precision Industry (ShenZhen) Co., Ltd., Hon Hai Precision Industry Co., Ltd.
    Inventors: Yi-Cai Tan, Ren-Jun Xiao, Zhi-Sheng Yuan
  • Patent number: 7816902
    Abstract: An integrated circuit includes a controller configured to regulate an output of a power supply based on a first signal. The integrated circuit includes an input configured to receive the first signal and to be coupled to an external capacitor that sets an adjustable blanking time for the power supply.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: October 19, 2010
    Assignee: Infineon Technologies Austria AG
    Inventors: Gong Xiao Wu, Lim Kok Kee, Kok Siu Kam
  • Patent number: 7813149
    Abstract: A power supply includes an input filter and rectifier module, a digital control module, and a converter module. The input filter and rectifier module is configured to rectify an input voltage. The digital control module is adapted to prevent a potential saturation of a transformer by setting a maximum allowable duty cycle for a control signal transmitted to the transistor based on an input voltage. The digital control model is further adapted to reduce switching losses in the power supply by setting the control signal switching frequency, based on the input voltage. The converter module is configured to convert the input voltage into a direct current output voltage based upon the control signal.
    Type: Grant
    Filed: September 21, 2007
    Date of Patent: October 12, 2010
    Assignee: Dell Products, LP
    Inventors: Lucian Popescu, Constantin D. Livescu
  • Patent number: 7782634
    Abstract: A switched-mode power supply includes a converter to convert input power into output power having a predetermined voltage level by performing a switching operation; a switching controller to control the switching operation of the converter based on an indication of a voltage of the output power; and an output power voltage indicating unit to provide the indication of the voltage of the output power to the switching controller according to a characteristic of the output power voltage indicating unit that varies according to the size of a load receiving the output power converted by the converter.
    Type: Grant
    Filed: May 30, 2008
    Date of Patent: August 24, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Tae-kwon Na
  • Patent number: 7773392
    Abstract: A primary side is provided with an oscillation circuit arranged to turn on a power switch at a constant cycle. The secondary side is provided with an on period control circuit arranged to output an off signal for turning the power switch off by detecting output voltage and comparing with a reference triangle wave signal. An isolated signal transfer circuit is provided between the primary side and secondary side to transfer an on signal. The primary side is provided with a power switch off circuit arranged to turn off the power switch based on the on signal.
    Type: Grant
    Filed: March 16, 2007
    Date of Patent: August 10, 2010
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Tadahiko Matsumoto
  • Patent number: 7746672
    Abstract: A switching power supply apparatus which includes a DC power supply, an isolation transformer having primary, secondary and tertiary windings, and a switching element, and in which, by turning the switching element on and off, the high-frequency voltage appearing in the secondary windings of the isolation transformer is rectified to obtain a DC output, power consumption can be decreased during standby (in burst mode) in particular by means of a control circuit which controls the turn-on and turn-off of the element and similar.
    Type: Grant
    Filed: June 20, 2008
    Date of Patent: June 29, 2010
    Assignee: Fuji Electric Device Technology Co., Ltd.
    Inventor: Yukihiro Nishikawa
  • Patent number: 7738266
    Abstract: This invention relates to control techniques and controllers for resonant discontinuous forward power converters (RDFCs). We describe a controller for a resonant discontinuous forward converter (RDFC), said forward converter including a transformer with first and second matched polarity windings and a switch to switch dc power to said first winding of said transformer, said converter further having a dc output coupled to said second winding of said transformer, and wherein said controller has two modes, a first operational mode during which said switch is controlled to switch said dc power at a frequency which substantially coincides with a resonant frequency of operation of said RDFC such that said RDFC supplies power from said dc output, and a second, reduced power operational mode during which a drive to said switch is controlled to increase a proportion of time during which said switch is off.
    Type: Grant
    Filed: December 15, 2006
    Date of Patent: June 15, 2010
    Assignee: Cambridge Semiconductor Limited
    Inventors: Russell Jacques, David Robert Coulson
  • Publication number: 20100135050
    Abstract: A comparator detects whether a feedback signal of an output voltage detecting circuit for a switching power supply circuit reaches a control voltage. A comparator detects an operating state of the switching power supply circuit, which is instructed by a switching instruction signal, by comparing the instruction signal with a reference voltage. The comparators are connected to a decision circuit which outputs to a control circuit a signal instructing a normal state until the feedback signal reaches the control voltage, and thereafter a signal instructing a normal state or a stand-by state that is instructed by the switching instruction signal. Thus, the control circuit makes the switching power supply circuit operate in a normal state until the output voltage reaches the control voltage. After the output voltage reaches the control voltage, the switching power supply circuit operated in an operation state instructed by the switching instruction signal to enable stable startup.
    Type: Application
    Filed: October 28, 2009
    Publication date: June 3, 2010
    Applicant: FUJI ELECTRIC SYSTEMS CO., LTD.
    Inventor: Koji SONOBE
  • Patent number: 7697309
    Abstract: The present invention provides an overpower-protection circuit and a power supply apparatus having the same. The power supply apparatus comprises a rectifier, a transformer and an overpower-protection circuit The overpower-protection circuit comprises a converter having a converter input electronically coupled to the rectifier and a converter output, a photo coupler having at least a first terminal coupled with the converter output, and having an output terminal, and a clipper electrically coupled across said terminals of the photo coupler for keeping the converter output below a predetermined voltage.
    Type: Grant
    Filed: January 16, 2007
    Date of Patent: April 13, 2010
    Assignee: Thomson Licensing
    Inventors: You Bing Bao, Wei Luo
  • Patent number: 7688869
    Abstract: In one embodiment, the invention relates to a serial line circuit that comprises a serial information (SI) bus and at most two isolators interposed between a pair of programmable devices. In the TRANSMIT direction, a first programmable device is configured to multiplex serial data received from a plurality of serial UARTs and to route such data to the second programmable device over the SI bus and through a first isolator. In the RECEIVE direction, the second programmable device is configured to sample data from a plurality of serial interconnects and to route the sampled data to the first programmable device. The sampled data is routed over the SI bus and through a second isolator. The data transmission over the SI bus is in accordance with a proprietary serial transmission protocol described below.
    Type: Grant
    Filed: February 19, 2004
    Date of Patent: March 30, 2010
    Assignee: Aruba Networks, Inc.
    Inventors: Joel F. Adam, Jerry Martinson
  • Publication number: 20100046252
    Abstract: Embodiments of the invention provide an off line DC-DC converter comprising a transformer (180) coupled to a monolithic integrated circuit (405). The transformer applies an input supply DC voltage (Vin) applied to a primary winding (181) of the transformer to produce an output supply DC voltage (Vout) provided from a secondary winding (182). The monolithic integrated circuit (400) comprises a switching regulator including a switch (151) and a switch controller (100) on a first portion of the monolithic integrated circuit. A capacitive isolator (201) is provided on a second portion of the monolithic integrated circuit. The monolithic integrated circuit regulates the output supply DC voltage and isolates the output supply DC voltage from the input supply DC voltage with respect to electrical shock hazard.
    Type: Application
    Filed: March 22, 2007
    Publication date: February 25, 2010
    Applicant: THOMSON LICENSING
    Inventor: Anton Werner Keller
  • Patent number: 7663896
    Abstract: An energy effective switching power supply apparatus and an energy effective method thereof. The energy effective switching power supply apparatus includes a power transforming part having first and second coils to induce a voltage to the second coil using interactions between the first and the second coils with respect to the input voltage, a power outputting part to output a sensing signal when it is determined that a first DC voltage output by rectifying and smoothing the voltage induced to the second coil is greater than or equal to a reference voltage level, and a switching controlling part to adjust a switching frequency of a switching device to interrupt a current flowing in the first coil of the power transforming part when the sensing signal is received. Accordingly, a switching loss is controlled and an energy loss is reduced.
    Type: Grant
    Filed: March 28, 2006
    Date of Patent: February 16, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Tae-kwon Na
  • Patent number: 7649280
    Abstract: A power equalization circuit in a transformer-based device having a plurality of isolated voltage outputs is provided. The circuit comprises: a threshold detection circuit configured to receive an error signal derived from a selected voltage at one of the isolated voltage outputs, and to determine whether the selected voltage is above a voltage threshold based on the error signal; a timer circuit configured to activate a wait signal after a maximum voltage drift time has expired since the selected voltage rose above the voltage threshold, and to activate a wink signal coincident with the wait signal; an overdrive current source configured to drive an error current to an overdriven value in response to the wait signal; and a commutator circuit connected to a transistor winding associated with the selected isolated voltage output, the commutator being configured to connect a transformer secondary winding to ground in response to the wink signal.
    Type: Grant
    Filed: September 21, 2007
    Date of Patent: January 19, 2010
    Assignee: Texas Instruments Incorporated
    Inventor: Michael Thomas Madigan
  • Publication number: 20090279327
    Abstract: In an isolated DC-DC converter, an on-period control circuit generates an off-timing signal when the output voltage of an isolated DC-DC converter exceeds a reference voltage. A signal reception/power switch driving circuit causes a first switching device to be turned on based on a pulse signal for switching that is output from a PWM control circuit, and causes the first switching device to be turned off based on an off-timing signal transmitted by an off-timing signal transmission unit. A bootstrap circuit boosts a control voltage of the first switching device with the pulse signal for switching that is output from the PWM control circuit.
    Type: Application
    Filed: July 27, 2009
    Publication date: November 12, 2009
    Applicant: Murata Manufacturing Co., Ltd.
    Inventor: Tadahiko MATSUMOTO
  • Patent number: 7548437
    Abstract: A switching mode power supply (SMPS) is presented to compensate for variations of maximum output power caused by variations of input power. The output power varies according to variations of input power because of a propagation delay of the SMPS. To compensate for the propagation delay, a reference voltage for turning off a switching MOS transistor is differently established depending on the input voltage. The variation of maximum output power according to the input voltage is prevented by differentiating the turned-off time of the reference voltage for turning off a main switch, such as a switching MOS transistor according to the input voltage.
    Type: Grant
    Filed: May 3, 2005
    Date of Patent: June 16, 2009
    Assignee: Fairchild Korea Semiconductor, Ltd.
    Inventors: Jin-Ho Choi, Dong-Young Huh, Yong-Chul Ryu
  • Patent number: 7548028
    Abstract: A high conversion efficiency inverter circuit by providing the current-mode resonant type efficient in using a power source.
    Type: Grant
    Filed: January 12, 2006
    Date of Patent: June 16, 2009
    Inventor: Masakazu Ushijima
  • Patent number: 7502233
    Abstract: There is provided a power supply for AC/DC and DC/DC conversion which receives the DC power supplied from airplanes, vehicles and vessels as well as normal AC power, and converts the power to DC power and supplies it to portable electronic products. The power supply for AC/DC and DC/DC conversion includes an AC input 10, a DC input 20, a switch 30 for selecting AC input power or DC input power, a DC output 40, and a circuit used for AC/DC and DC/DC conversion 100 which converts the power input from the AC input or the DC input to DC power having predetermined values of current and voltage, and a secondary side of a transformer (TL) for AC/DC conversion inside the circuit for conversion serves as an inductor for performing DC/DC conversion.
    Type: Grant
    Filed: December 19, 2006
    Date of Patent: March 10, 2009
    Assignee: Smart Power Solutions Inc.
    Inventors: Hyun-Jun Kim, Dae-Young Youn, Sang-Min Kim
  • Publication number: 20090046483
    Abstract: A switched-mode power supply includes a converter to convert input power into output power having a predetermined voltage level by performing a switching operation; a switching controller to control the switching operation of the converter based on an indication of a voltage of the output power; and an output power voltage indicating unit to provide the indication of the voltage of the output power to the switching controller according to a characteristic of the output power voltage indicating unit that varies according to the size of a load receiving the output power converted by the converter.
    Type: Application
    Filed: May 30, 2008
    Publication date: February 19, 2009
    Applicant: Samsung Electronics Co., Ltd.
    Inventor: Tae-Kwon NA
  • Patent number: 7478254
    Abstract: A switching power supply device has a large load power supply line for a CRT circuit, to and from which a dummy resistor for voltage stabilization is connected and disconnected by a switch. In standby state, a control unit turns off the switch to disconnect the dummy resistor from the power supply line. When receiving a power supply ON command input by a user operating a remote control, the control unit turns on the switch to connect the dummy resistor to the power supply line. At a predetermined time after the dummy resistor connection, the control unit makes a regulator active to start providing voltage to a video/audio signal processing circuit with sufficient current providable thereto. This enables to reduce power consumption of the power supply line with the dummy resistor, and to prevent problems caused by insufficient current in transient state from standby state to power supply ON state.
    Type: Grant
    Filed: March 28, 2006
    Date of Patent: January 13, 2009
    Assignee: Funai Electric Co., Ltd.
    Inventor: Yoshikazu Kawai
  • Patent number: 7453243
    Abstract: If an intermittent oscillation pulse in a case in which the power consumption in the standby state is reduced at the maximum is supplied to a connection point from an output port of a microcomputer through a capacitor and a resistor, a DC component of the intermittent oscillation pulse is removed and is then supplied to the connection point. At this time, even when a voltage of the connection point becomes larger than a power supply voltage of the microcomputer, since a current does not flow backward from the connection point to the microcomputer, the microcomputer is normally operated. As such, the microcomputer is normally operated, so that the intermittent oscillation pulse is effectively supplied to the connection point. Thereby, a transistor is intermittently operated, the oscillation circuit intermittently performs oscillation operation, and the power consumption in the standby state is reduced.
    Type: Grant
    Filed: November 4, 2005
    Date of Patent: November 18, 2008
    Assignee: Funai Electric Co., Ltd.
    Inventor: Masato Suekuni
  • Publication number: 20080265133
    Abstract: An integrated circuit is disclosed that integrates a low current, high speed optical receiver with the primary side control functions of the power supply. This is further combined with an optical emitter to create a single component for feedback and control, providing improved performance and manufacturing. A method of providing feedback for the power supply using such an integrated optically coupled control circuit is also disclosed.
    Type: Application
    Filed: April 30, 2008
    Publication date: October 30, 2008
    Inventors: Carl K. Sawtell, Paolo Menegoli
  • Patent number: 7440295
    Abstract: A switching mode power supply (SMPS) with an active load detection function which supplies AC power input to a primary coil of a transforming element, then to a secondary coil of the transforming element, and then rectifies and outputs the AC power is provided. The SMPS comprises a controlling unit for controlling switching frequency by changing the time constant of a switching unit depending on the current and reducing the amount of power supplied to the primary coil of the transforming element. The current at a terminal of a resistor can be controlled under a cross condition, and the current flowing to the resistor can be controlled when in a normal state, thereby preventing energy loss which always occur in the resistor. The switching frequency during a standby state can be reduced to reduce switching loss.
    Type: Grant
    Filed: May 10, 2006
    Date of Patent: October 21, 2008
    Assignee: Samsung Electronics Co., Ltd
    Inventor: Tae-Kwon Na
  • Patent number: 7433208
    Abstract: A switching power supply device includes a primary winding of a transformer that is connected in series to a first switching element, and a secondary winding is provided with a rectifier circuit and an output voltage control circuit arranged to detect an output voltage and feed it back to a control circuit. The control circuit is provided with an on-period control circuit arranged to turn off the first switching element in an on-state based on a feedback signal from the output voltage control circuit and an off-period control circuit arranged to control an off-period thereof by delaying turn-on of the first switching element based on the feedback signal.
    Type: Grant
    Filed: April 20, 2005
    Date of Patent: October 7, 2008
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Akio Nishida, Fumi Kitao, Hiroshi Takemura
  • Patent number: 7415072
    Abstract: The invention relates to a drive control for an electric drive with a secure electrical separation of power element and control element. The aim of the invention is to reduce the number of components such as optic couplers and buffer amplifiers between the power element and a control electronics. To this end, a suitable electrical transformer (U) is inserted in a digital communication interface (K) between the control unit (R) and the control electronics (A) for the purpose of providing a secure electrical separation. To make use of a transformer (U) possible, a non-zero frequency encoding, for example a Manchester encoding, is carried out. Alternatively, an Ethernet physics can be used to provide a suitable communication interface. The transformer electrically insulates the two communication paths from each other that are provided in an Ethernet physics and preferably has little coupling capacity and a low attenuation factor.
    Type: Grant
    Filed: September 17, 2001
    Date of Patent: August 19, 2008
    Assignee: Siemens Aktiengesellschaft
    Inventors: Susanne Gaksch, Kurt Göpfrich, Peter Heidrich, Franz Imrich, Peter Jänicke
  • Patent number: 7414865
    Abstract: A controller controls the output current by measuring and controlling the switching current of the power converter. A first circuit generates a first signal in accordance with the switching current. A second circuit detects a discharge-time of the transformer. A third circuit generates a third signal by integrating the first signal with the discharge-time. The time constant of the third circuit is programmed and correlated with the switching period of the switching signal, therefore the third signal is proportional to the output current. A switching circuit generates a switching signal and controls the pulse width of the switching signal in accordance with the third signal and a reference voltage. Therefore, the output current of the power converter can be regulated.
    Type: Grant
    Filed: November 17, 2005
    Date of Patent: August 19, 2008
    Assignee: System General Corp.
    Inventor: Ta-Yung Yang
  • Patent number: 7400517
    Abstract: In one embodiment, a power factor correction circuit is configured to use a stored value of a feedback signal to assist in regulating the value of an output voltage and to bypass the sample and hold circuit if the output voltage increase to an upper limit or decreases to a lower limit.
    Type: Grant
    Filed: July 3, 2006
    Date of Patent: July 15, 2008
    Assignee: Semiconductor Components Industries, L.L.C.
    Inventor: Terry Allinder
  • Patent number: 7382062
    Abstract: The invention finds application in the field of power supplies for valve actuators, and particularly relates to a wide voltage range stabilized switching power supply for valve actuators, of the type that comprises a filter 2, a diode bridge 3, an array of capacitors 5, an auxiliary power supply stage 6, formed by a switch mode circuit, having an operating range of 21 to 380 VDC, which generates the supply voltages required for the internal operation of the power supply, a full-bridge power stage 7, which receives an input voltage in the range of 120 VDC to 373 VDC, and generates the three stabilized output voltages required for supplying the load, and a boost stage 4, located upstream from the power stage 7, which allows to increase the voltage to a value in the range of 120 VDC to 373 VCC, whenever it is below such range.
    Type: Grant
    Filed: November 4, 2004
    Date of Patent: June 3, 2008
    Assignee: Biffi Italia S.R.L.
    Inventors: Archimede Affaticati, Giuseppe Riboli
  • Patent number: 7345431
    Abstract: A DC/AC converter circuit structure for driving a plurality of cold cathode fluorescent lamps is described. A common-mode choke is used between the cold cathode fluorescent lamps. The common-mode choke balances the currents respectively flowing through the cold cathode fluorescent lamps.
    Type: Grant
    Filed: March 13, 2007
    Date of Patent: March 18, 2008
    Assignee: O2Micro International Limited
    Inventor: Sheng Tai Lee
  • Patent number: 7345894
    Abstract: A switching power supply is disclosed for improving the no-load power drain of low-power mains operated supplies. The power converter utilizes a cascoded switch arrangement with a conventional high voltage power MOSFET and a low voltage, low gate charge MOSFET. Driving only the small low voltage device reduces the power required for gate drive. The disclosed configuration is also capable of generating a non-isolated auxiliary rail for powering its control circuitry utilizing the parasitic capacitance of the high voltage power devices as an element in a charge pump. The resulting power supply requires significantly fewer components.
    Type: Grant
    Filed: September 7, 2006
    Date of Patent: March 18, 2008
    Assignee: Carl Sawtell
    Inventors: Carl K. Sawtell, Paolo Menegoli
  • Patent number: 7336057
    Abstract: A DC/DC converter includes: a boost converter that boosts an input voltage in accordance with a first control signal; an insulated converter that converts an output of the boost converter in accordance with a second control signal; a current sensor that detects an output current of the insulated converter; a first controller that generates the first control signal based on an error between the output current detected by the current sensor and a first threshold value; and a second controller that generates the second control signal based on an error between the output current detected by the current sensor and a second threshold value that is larger than the first threshold value.
    Type: Grant
    Filed: April 26, 2006
    Date of Patent: February 26, 2008
    Assignee: Kabushiki Kaisha Toyota Jidoshokki
    Inventor: Nobuo Hirabayashi
  • Patent number: 7289339
    Abstract: An inverter circuit for inhibiting electricity transmission interference receives an electric signal output from an electricity input circuit, and includes a control unit to output an operating frequency, an actuation circuit to receive the operating frequency and divide the electric signal and output an actuation signal, and a transformer to receive the actuation signal and transform electricity to actuate a first load to operate. The actuation unit and the control unit are bridged by an isolation unit which separates grounding of the actuation unit and control unit on the first side and the second side of the transformer to enable the control unit to output the steady operating frequency and inhibit electric transmission interference.
    Type: Grant
    Filed: September 28, 2004
    Date of Patent: October 30, 2007
    Assignee: Zippy Technology Corp.
    Inventors: Chin-Wen Chou, Ying-Nan Cheng, Chin-Biau Chung
  • Patent number: 7236376
    Abstract: A controller controlling the output current at the primary side of a power supply is provided. A waveform detector generates a current-waveform signal. A second control circuit generates an oscillation signal for determining the switching frequency of a switching signal. An integrator generates an integrated signal by integrating an average current signal with a time signal. The average current signal is generated in response to the current-waveform signal. The time signal is generated in accordance with said oscillation signal. The time constant of the integrator is correlated with the switching period of the switching signal, therefore the integrated signal is proportional to the output current. A first control circuit generates the switching signal in correlated with the integrated signal, the oscillation signal and a reference voltage. Wherein the first control circuit controls the pulse width of the switching signal. Therefore, the output current of the power supply can be regulated.
    Type: Grant
    Filed: November 17, 2005
    Date of Patent: June 26, 2007
    Assignee: System General Corp.
    Inventor: Ta-Yung Yang
  • Patent number: 7212417
    Abstract: A transformer has a primary winding connected to a pair of DC input terminals via an active switch, and a secondary winding connected to a pair of DC output terminals via a first rectifying and smoothing circuit. The active switch is driven constantly under normal load, and at intervals under light load, under the direction of a switch control circuit. This switch control circuit is powered with a control voltage fed from a second rectifying and smoothing circuit which is connected to a tertiary winding of the transformer. In order to preclude malfunctioning or nonoperation in the event of an abnormal drop of the control voltage during operation in light load mode, the switch control circuit is equipped to drive the active switch at shorter intervals in control voltage recovery mode when the control voltage falls below a predefined limit than the normal intervals of the light load mode.
    Type: Grant
    Filed: June 29, 2006
    Date of Patent: May 1, 2007
    Assignee: Sanken Electric Co., Ltd.
    Inventor: Yukinari Fukumoto
  • Patent number: 7203041
    Abstract: There is disclosed a power conversion circuit including self synchronous rectifiers and a rapid shutdown section. When power is removed from the power conversion circuit, the rapid shutdown section prevents self oscillation of the self synchronous rectifiers. As a result, power is not drawn from the output and dissipated in the power conversion circuit.
    Type: Grant
    Filed: May 10, 2004
    Date of Patent: April 10, 2007
    Assignee: Power-One, Inc
    Inventors: David Arthur Williams, Donald R. Caron, Ram Ramabhadran
  • Patent number: 7200016
    Abstract: An error detection circuit includes: a Zener diode having a cathode connected through a resistor to a second DC output with a higher voltage than that of a first DC output; a voltage divider circuit; and a PNP transistor having an emitter connected to the first DC output, and a base supplied with an output voltage of the voltage divider circuit. A Zener voltage of the Zener diode and a voltage dividing ratio of the voltage divider circuit are set so that the output voltage of the voltage divider circuit is equal to a value obtained by subtracting the base-emitter voltage of the PNP transistor Q1 from the voltage of the first DC output, and that temperature characteristic of the output voltage of the voltage divider circuit is set at a value canceling temperature characteristic of the PNP transistor.
    Type: Grant
    Filed: December 17, 2003
    Date of Patent: April 3, 2007
    Assignee: Funai Electric Co., Ltd.
    Inventor: Takahiro Ogawa
  • Patent number: 7190123
    Abstract: A DC/AC converter circuit structure for driving a plurality of cold cathode fluorescent lamps is described. A common-mode choke is used between the cold cathode fluorescent lamps. The common-mode choke balances the currents respectively flowing through the cold cathode fluorescent lamps.
    Type: Grant
    Filed: August 24, 2004
    Date of Patent: March 13, 2007
    Assignee: O2Micro International Limited
    Inventor: Sheng Tai Lee
  • Patent number: 7187563
    Abstract: An electronic circuit includes a first power source, a second power source, a load, and a converter connected to each power source and the load. The converter has (i) a first oscillator circuit connected to the first power source, (ii) a second oscillator circuit connected to the second power source, the first and second oscillator circuits being electrically isolated from each other, (iii) an isolation transformer which includes a first primary winding connected to the first oscillator circuit, a second primary winding connected to the second oscillator circuit, and a secondary winding coupled to the first and second primary windings by magnetic inductance, and (iv) a rectifier circuit connected to the second winding and the load.
    Type: Grant
    Filed: June 23, 2004
    Date of Patent: March 6, 2007
    Assignee: Cisco Technology, Inc.
    Inventor: Pavlo Bobrek
  • Patent number: 7130201
    Abstract: The present invention discloses a power supply device for outputting a stable programmable power supply, which comprises a transformer disposed at a DC output end of the power supply device, and a clamp circuit connected to a secondary current of the transformer. Since the clamp circuit is disposed on the secondary current of the transformer, therefore it does not require a high DC voltage to drive the clamp circuit. The clamp circuit can release the high voltage produced when the metal oxide semiconductor field effect transistor (MOSFET) is off, and thus reducing the high voltage borne by the MOSFET to enhance the reliability of the MOSFET. Additionally, the present invention can prevent the transformer from being saturated due to magnetic leakage, inductance, and stored energies released or eliminated from the transformer.
    Type: Grant
    Filed: May 14, 2004
    Date of Patent: October 31, 2006
    Assignee: Grand Power Sources Inc.
    Inventor: Pei-Chih Yao
  • Patent number: 7079405
    Abstract: A thermal conductive polymer molded article is formed by molding a thermotropic liquid crystalline composition comprised mainly of a thermotropic liquid crystalline polymer, wherein the thermal conductive polymer molded article is formed by applying a magnetic field or an electric field to the thermotropic liquid crystalline composition melted by heating so that the thermal conductive polymer molded article has a first thermal conductivity (?1) higher than a second thermal conductivity (?2) of a molded article formed by molding the thermotropic liquid crystalline polymer without the application of the field. The thermal conductive polymer molded article preferably has a first thermal conductivity (?1) of between 0.7 and 20 W/(m·K). Preferably, the thermotropic liquid crystalline polymer comprises at least one polymer selected from (A) a wholly aromatic polyester and (B) a wholly aromatic polyester amide.
    Type: Grant
    Filed: July 11, 2003
    Date of Patent: July 18, 2006
    Assignee: Polymatech Co., Ltd.
    Inventors: Masayuki Tobita, Toru Kimura, Naoyuki Shimoyama, Tsukasa Ishigaki
  • Patent number: 7057907
    Abstract: A power converter using a microcontroller is disclosed herein. In one embodiment, the power converter can be a digital flyback or forward converter. The microcontroller may have a digital pulse-width-modulation (PWM) controller, arithmetic logic unit (ALU) core, internal random access memory (RAM), read-only memory (ROM), and one or more analog-to-digital (A/D) and digital-to-analog (D/A) converters. For a fast dynamic response in an inner current control loop, an analog comparator is used to provide analog-based current control. The analog comparator may compare a signal representative of the current flowing in the power converter against a voltage reference, which can be programmable. The analog comparator may be integrated with the digital microcontroller into single integrated circuit (IC) chip. Furthermore, the power converter can send signals for the status of various conditions (e.g., output voltage levels, current levels, errors, etc.) or can receive signals for system control commands (e.g.
    Type: Grant
    Filed: November 21, 2003
    Date of Patent: June 6, 2006
    Assignee: Fairchild Semiconductor Corporation
    Inventor: In-Hwan Oh
  • Patent number: 7038432
    Abstract: A linear predictive system for a DC—DC converter including a linear predictive controller, first and second adders and a multiplier. The DC—DC converter generates an output signal and includes a digital compensation block that converts a feedback error signal into a main duty cycle signal. The linear predictive controller predicts linear changes of the main duty cycle signal in response to changes of the output signal and provides a predictive duty cycle signal. The first adder subtracts the predictive duty cycle signal from the main duty cycle signal to provide a duty cycle delta. The multiplier multiplies the duty cycle delta by a gain factor to provide a duty cycle delta sample. The second adder adds the duty cycle delta sample to the first duty cycle signal to generate an adjusted duty cycle signal.
    Type: Grant
    Filed: April 19, 2004
    Date of Patent: May 2, 2006
    Assignee: Intersil Americas Inc.
    Inventor: Zaki Moussaoui