With Automatic Control Of The Magnitude Of Output Voltage Or Current Patents (Class 363/19)
  • Patent number: 6819226
    Abstract: The invention involves systems and methods of providing energy to land-based telemetry devices wherein the energy storage and power conditioning system is comprised of an input power supply, an energy storage element, an output supply and a control system. The input power supply provides energy to the output power supply and charges the energy storage element. The energy storage element is comprised of one or more UltraCaps and supplies energy to the output power supply at times of peak need and when the primary energy source to the input power supply is removed. The control system adjusts the voltage supplied to the energy storage element by the input power supply according to changes in the ambient temperature to compensate for changes in the internal equivalent series resistance of the UltraCaps caused by the change in ambient temperature. The output power supply provides energy to the land-based telemetry device.
    Type: Grant
    Filed: April 9, 2003
    Date of Patent: November 16, 2004
    Assignee: SmartSynch, Incorporated
    Inventor: Bruce E. Randall
  • Patent number: 6816392
    Abstract: An overcurrent output protector is electrically connected to a constant-voltage switching power supply provided with a switching transistor which converts a DC voltage obtained by smoothing an AC voltage supplied from an AC power source into a cyclic pulse signal. In the overcurrent output protector, duty ratio monitor judges whether an ON duty ratio of the cyclic pulse signal is a predetermined ratio or more. A deactivator turns off the switching transistor in a case where the duty ratio monitor judges that the ON duty ratio is the predetermined ratio or more.
    Type: Grant
    Filed: May 8, 2003
    Date of Patent: November 9, 2004
    Assignee: Seiko Epson Corporation
    Inventor: Seiji Takamatsu
  • Publication number: 20040208024
    Abstract: Disposed in a secondary side circuit and is connected to a constant voltage control circuit (22), to an overcurrent detection circuit (24), and to an overvoltage detection circuit (26), a photocoupler control circuit (28) controls a photocoupler (IC1) so as to feed a constant voltage detection control signal as a feedback signal back to a primary side circuit. The photocoupler control circuit (28) controls the photocoupler (IC1) so as to turn it off when the photocoupler control circuit is supplied with at least one of an overcurrent detected signal and an overvoltage detected signal. A voltage detection circuit (18) makes a latch circuit (16) operate when the voltage detection circuit detects a voltage induced in an auxiliary winding (NSLD) of a transformer with the photocoupler turned off, thereby making a switching operation of a switching type AC adapter circuit stop.
    Type: Application
    Filed: February 26, 2004
    Publication date: October 21, 2004
    Applicant: Mitsumi Electric Co. Ltd.
    Inventors: Junji Nagano, Kouji Murakami
  • Publication number: 20040196671
    Abstract: A complex resonance type switching converter provided with a self-excited voltage resonance type converter has a conduction controlling device Q2 connected in series with a control winding Nc of a drive transformer CDT in which a detecting winding NA, a driving winding NB of a self-oscillation driving circuit, and the control winding Nc are wound on an identical core. An amount of current conducted in the conduction controlling device Q2 is varied, whereby a level of a base current flowing from the self-oscillation driving circuit to a base of a switching device Q1 is changed and switching frequency of the switching device Q1 is variably controlled. Thereby a conduction angle and the switching frequency of the switching device are changed simultaneously, and consequently constant-voltage control is effected on a direct-current output on the secondary side of the converter. Use of such a drive transformer CDT makes it possible to prevent variations of the self-oscillation driving circuit and reduce size.
    Type: Application
    Filed: May 14, 2004
    Publication date: October 7, 2004
    Inventor: Masayuki Yasumura
  • Publication number: 20040196670
    Abstract: This invention relates to a digital time mirrored pulse width modulate controller. The controller is electrically connected to a converter unit in which it comprises at least one comparator unit. The comparator unit outputs/inputs a voltage (Vo) and a preset voltage (Vset), and outputs a phase signal having low-level and high-level standards and a core digital processing unit, wherein the core digital processing unit outputs a pulse width modulate signal, through the units mentioned above. The characteristics of the invention can be summed up as follows: the elapsed time of the phase signal in high-level and in low-level is equal, and the root mean square of the output voltage in converter unit is equal to the preset voltage (Vset).
    Type: Application
    Filed: April 3, 2003
    Publication date: October 7, 2004
    Inventors: Chin-Tsai Hong, Chung-Fu Chou, Chun-Ting Lu, Thou-Vun Pang
  • Publication number: 20040196669
    Abstract: Self-oscillating, current controlled switching power supplies, used for example, as energy storage device charging circuits, and related methods are provided herein. In one implementation, a switching power supply comprises a power transformer having a primary and a secondary, a switching element that switches a voltage source to the primary, and a control circuit that controls the operation of the switching element in response to the measured primary current and secondary current. The switching element disconnects the voltage source from the primary when the primary current reaches a first threshold, causing the secondary current to conduct. The switching element switches back to the primary when the secondary current drops to second threshold. The switching power supply oscillates between charging and discharging the power transformer. In one embodiment, a high value energy storage capacitor is coupled to the secondary and is charged with the secondary current.
    Type: Application
    Filed: April 1, 2003
    Publication date: October 7, 2004
    Applicant: Maxwell Technologies, Inc.
    Inventor: Guy C. Thrap
  • Patent number: 6798671
    Abstract: The present invention provides a worldwide compatible switching power supply unit of an RCC system in which by reducing the number of components or parts, reduction of cost can be realized and the mounting space can be reduced. In a high input voltage and in a light load, an inductance of a primary winding of a transistor is set high but in the range of not exceeding a rated value of a main switching element, and in a low input voltage and in a heavy load, an inductance of a primary auxiliary winding and values of a control resistor and a capacitor of the main switching element are set low but in the range of not deteriorating the starting characteristics of the main switching element.
    Type: Grant
    Filed: June 10, 2003
    Date of Patent: September 28, 2004
    Assignee: Orion Electric Company, Ltd.
    Inventor: Hiroshi Sakai
  • Publication number: 20040174721
    Abstract: A switching power supply unit includes a transformer, a switching circuit disposed on a primary side of the transformer, a self-driven type synchronous rectifier circuit disposed on a secondary side of the transformer and including a rectifier switch, and a self-oscillation stop circuit disposed on the secondary side of the transformer and adapted to turn off the rectifier switch when a voltage between opposite ends of the rectifier switch exceeds a predetermined value.
    Type: Application
    Filed: March 2, 2004
    Publication date: September 9, 2004
    Applicant: TDK Corporation
    Inventor: Junichi Yamamoto
  • Publication number: 20040156216
    Abstract: A commercially available power source is rectified by a diode bridge and a capacitor and supplied to a transformer via a terminal. One end of a primary coil is connected to the terminal and the other end is connected to a switching device. One end of a feedback coil is connected to the switching device and the other end is connected to the terminal. A negative feedback circuit is provided between the switching device and the terminal. A rectifying circuit comprising a diode and a capacitor is provided on a secondary coil. A node of the coil and the capacitor is connected to the terminal via a resistor. In detecting circuits, a voltage across the terminal is detected and a current across the resistor is detected. When the detected voltage and current are equal to predetermined values, a control signal is supplied to a feedback circuit.
    Type: Application
    Filed: July 24, 2003
    Publication date: August 12, 2004
    Inventors: Tamiji Nagai, Tamon Ikeda, Kazuo Yamazaki
  • Patent number: 6765809
    Abstract: A power source including a transformer having a primary coil, a secondary coil, and a feedback coil; a resonance capacitor connected in parallel with the primary coil of the transformer in parallel, a switching unit having an input terminal which receives an input voltage input from the feedback coil of the transformer and which controls a current through the primary coil of the transformer according to the input voltage; and a current detection unit which detects the current in order to turn off the switching unit when the detected current is higher than a predetermined current. An output voltage stabilization circuit controls the input voltage at the input terminal of the switching unit, proportional to a voltage output by the secondary coil of the transformer.
    Type: Grant
    Filed: October 9, 2002
    Date of Patent: July 20, 2004
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Chihiro Komori
  • Patent number: 6693406
    Abstract: The present invention relates to a method and an apparatus for controlling an electric motor by regulating at least the current Iout, the voltage Uout and the frequency fout to an input of said motor, where the number of revolutions of said electric motor is proportional to said frequency fout. If an available power Pin from an energy source is greater than or equal to the nominal requested power Pnom of said electric motor, the current Iout, voltage Uout and frequency fout are set to there corresponding nominal values Inom, Unom and fnom, respectively, to achieve said requested power Pnom and frequency fnom. If said available power Pin is less than the requester power Pnom, the voltage Uout and the frequency fout are reduced such that the relation between the voltage Uout and the frequency fout is essentially constant while said current Iout is kept at its nominal value Inom.
    Type: Grant
    Filed: June 25, 2002
    Date of Patent: February 17, 2004
    Assignee: Dometic Applicances AB
    Inventors: Thomas Korssell, Ulf Jacobson, Robert Karlsson
  • Patent number: 6690586
    Abstract: A self-excited oscillation type switching power source device is constructed such that when a power source switch is turned on, and the voltage of an input power source increases, the voltage at a point a is increased. When the voltage exceeds a predetermined voltage, a first transistor is turned on, and a second transistor is turned off. Then, a first switching element, when a starting voltage is applied to the control terminal thereof, is turned on, and voltage is developed in a first drive winding. This voltage is fed back to the point a via a feedback circuit. As a result, the transistor is accelerated to reach the on-state. The second transistor is accelerated to reach the off-state. As a result, the first switching element is rapidly turned on, and the oscillation is started.
    Type: Grant
    Filed: May 23, 2002
    Date of Patent: February 10, 2004
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Tatsuya Hosotani, Hiroshi Takemura
  • Patent number: 6657877
    Abstract: A power supply circuit improves the power factor when the load is light, and incorporates a starting circuit for reacting quickly to the changes in the output from the power supply circuit and a short-circuit detecting means for detecting the short-circuit of the feedback signal. The apparatus includes: an error amplifier; a comparator that monitors the output from the error amplifier and generates an offset regulating current ISO; a multiplier; a sensing current comparator that compares the output signal from the multiplier and the AC line current and generates a reset signal; a timer that directly monitors the inputted zero-cross signal; and a comparator for short-circuit detection, that facilitates reducing the exterior parts and components.
    Type: Grant
    Filed: September 28, 2001
    Date of Patent: December 2, 2003
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Masato Kashima, Mitsuru Sato, Eiji Kuroda, Hironobu Shiroyama
  • Patent number: 6643144
    Abstract: A circuit configuration for pulsed application of a first supply voltage to a load includes a first switch, connected in series with the load, a first control connector, a control circuit for control of the first switch and having a first output terminal connected to the control connector of the first switch and first and second voltage supply terminals, a second switch connected between the load and the first voltage supply terminal of the control circuit and having a second control connector to which a control signal is supplied. The invention also includes a method for actuating the first and second switches and use of the inventive circuit configuration in a switched-mode power supply or a power factor controller.
    Type: Grant
    Filed: July 15, 2002
    Date of Patent: November 4, 2003
    Assignee: Infineon Technologies AG
    Inventor: Martin Feldtkeller
  • Patent number: 6643147
    Abstract: A method of improving modulation resolution in a flyback converter by pulsewidth- and/or position-modulation of a subtractive constant current with specific timing considerations is applicable to boost or buck/boost topologies. A typical system of this type uses a pulsewidth-modulated (PWM) circuit to provide a control pulsewidth in response to an incoming data stream. The control pulsewidth is used to drive a switching device which, when energized, charges an inductor. When the switching device is released the energy stored in the inductor “flies back” through a diode into a capacitor and load resistance. According to this invention, a constant current sink, gated under control of the PWM controller, is used to improve modulation resolution through pulsewidth- and position-modulation of a subtractive constant current with specific timing considerations. In the preferred embodiment, the constant current sink is implemented using a transistor in conjunction with a resistor network.
    Type: Grant
    Filed: June 11, 2002
    Date of Patent: November 4, 2003
    Assignee: JAM Technologies, LLC
    Inventor: Larry Kirn
  • Patent number: 6639811
    Abstract: A switching power supply unit includes first and second switching elements which are alternately turned on/off so as to perform self-excited oscillation. An inductor and a capacitor resonate during an OFF-period of the first switching element. After the second switching element is turned on, a resonance current applied to a series circuit including the second switching element and the indictor is interrupted before energy is completely emitted from a secondary winding. Accordingly, a voltage is generated at the inductor and a voltage at a transformer is reversed. The switching power supply unit also includes an ON-time control circuit in which a time constant is set so as to turn off the second switching element accordingly.
    Type: Grant
    Filed: September 3, 2002
    Date of Patent: October 28, 2003
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Tatsuya Hosotani, Hiroshi Takemura
  • Patent number: 6633156
    Abstract: A device for monitoring the flow of a current in a load powered by a DC voltage source and a method for the implementation of the device. The device includes, series-connected with the load, a first device to detect the presence of an alternating current and a second device to interrupt the current flowing in the first device while keeping the current substantially direct in the load. Advantageously, the second device includes at least one first electronic switch series-connected with the load and with the first device, the first electronic switch being controlled so as to set up the alternating current in the first device. A method of implementing the device cyclically opens and closes the electronic switch while making the second device operable or inoperable, also cyclically, to keep the current substantially direct in the load and let the current flowing in the load pass through the second device only periodically.
    Type: Grant
    Filed: September 19, 2001
    Date of Patent: October 14, 2003
    Assignee: Thales Avionics S.A.
    Inventor: Joël Choisnet
  • Patent number: 6631079
    Abstract: A switching power supply apparatus comprises a transformer having primary winding and at least two secondary windings, a first switching element connected in series with the primary winding, a control circuit for controlling the output from the first switching element by control of the on-time thereof, a rectification circuit for rectifying at least two outputs from the secondary windings, an output detection circuit for detecting the output voltages and feeding back the output voltages as a control signal for control of the on-time to the control circuit. The output voltage detection circuit comprises a control signal formation section in which the control signal for the on-time is formed, corresponding to a voltage at a voltage comparison terminal, and plural voltage detectors connected between the at least two outputs of the secondary windings and the voltage comparison terminal, respectively.
    Type: Grant
    Filed: April 5, 2002
    Date of Patent: October 7, 2003
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Tatsuya Hosotani, Hiroshi Takemura, Takahiro Minagawa
  • Publication number: 20030174520
    Abstract: A voltage converter including a transformer having a primary winding connected in series with a switch for cutting-up a supply voltage and having a secondary winding associated with a capacitor providing a D.C. low voltage, and a self-oscillating control circuit of the switch for detecting the end of the demagnetization of an auxiliary winding of the transformer, to turn the switch on, and for detecting the current in the on-state switch to turn it off when this current reaches a reference point. The reference point is made variable according to the voltage across the auxiliary winding.
    Type: Application
    Filed: February 10, 2003
    Publication date: September 18, 2003
    Inventor: Igor Bimbaud
  • Patent number: 6614667
    Abstract: A power conversion apparatus capable of reducing the conduction loss to achieve high efficiency yielding a downsized and weight-reduced apparatus and a method for driving such a power conversion apparatus is disclosed. A power conversion apparatus comprising a switching-element driving circuit which includes a current transformer having a primary coil connected to an current control type switching element, and a driving-current generating circuit formed of a secondary coil of the current transformer and a rectifying circuit connected to the secondary coil, wherein an output current generated in the driving-current generating circuit is supplied to the switching element as a driving current of the switching element, and a method for driving the switching element of such a power conversion apparatus are disclosed.
    Type: Grant
    Filed: April 23, 2001
    Date of Patent: September 2, 2003
    Assignee: TDK Corporation
    Inventors: Kazuyuki Itoh, Yoshihisa Okita, Katsuaki Tanaka, Yoshinobu Takayanagi
  • Patent number: 6608768
    Abstract: A switched-mode power supply has primary and secondary sides, and a transformer (M1) with a primary winding, a secondary winding and an auxiliary winding. The primary winding and the auxiliary winding are connected to the primary side, and the secondary winding is connected to the secondary side. A switch element (T3) is connected to the primary winding in order to interrupt a current flowing in the primary winding. The switched-mode power supply contains a freely oscillating circuit (R5, C3, R7, T1, T2, R8, R9, R10, R11) for generating switching pulses to the switch element (T3). A rectifying and charge storing coupling (D4, C5) is connected between the terminals of the auxiliary winding in order to generate such an image voltage which on the primary side represents a certain voltage of the secondary side.
    Type: Grant
    Filed: July 10, 2002
    Date of Patent: August 19, 2003
    Assignee: Salcomp Oy
    Inventor: Matti Sula
  • Patent number: 6577511
    Abstract: A switching power supply unit includes a control circuit including a turn-off circuit for turning of a first switch element Q1, which has been in an ON state, and an off-period control circuit for, based on a feedback signal from an output-voltage detecting circuit, controlling the turning-on of the first switch element to be further delayed as a load is lighter. The off-period control circuit includes a transistor as a second switch element which is provided in series between a feedback winding and the control terminal of the first switch element and which is controlled to be turned on and off based on the feedback signal from the output-voltage detecting circuit. A switching frequency is set to be lower as the load is lighter, such that power consumption at the light load is reduced.
    Type: Grant
    Filed: March 5, 2002
    Date of Patent: June 10, 2003
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Satoshi Yamaguchi, Akio Nishida, Hiroshi Takemura
  • Patent number: 6567280
    Abstract: A method and a circuit for detecting a light load mode of a switching power supply system are provided. The switching power supply system has a first winding, a second winding, a third winding having a voltage being in proportion to an output voltage of the second winding, and a signal converting device electrically connected to the third winding. The method includes steps of measuring a voltage of the signal converting device, and determining the switching power supply system being under the light load mode when the voltage of the signal converting device is smaller than a predetermined threshold voltage.
    Type: Grant
    Filed: October 3, 2001
    Date of Patent: May 20, 2003
    Assignee: Delta Electronics, Inc.
    Inventor: Wang Kuo Jung
  • Patent number: 6552623
    Abstract: A switching transistor is connected to a primary winding of a transformer, an oscillation frequency control circuit is connected to a feedback winding, the oscillation frequency control circuit controls a first controlling transistor, and the first controlling transistor controls the delay time when the switching transistor is turned on. The oscillation frequency control circuit is set in a first operation mode in which the above delay does not take place at the rated load, in a second operation mode in which the oscillation frequency is controlled such that the oscillation frequency becomes constant or slowly decreases at light loading and in a third operation mode in which the oscillation frequency is further decreased while a switch is switched on.
    Type: Grant
    Filed: October 22, 2001
    Date of Patent: April 22, 2003
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Akio Nishida, Ryota Tani, Koji Nakahira
  • Patent number: 6542388
    Abstract: An intermittent switching power supply circuit prevents excessive output power on a secondary side of a circuit. An intermittent oscillator is alternately switched on and off to maintain output voltage and/or current roughly constant. An output power monitoring circuit monitors output power from a rectifying/smoothing circuit. A control circuit outputs a stop control signal to an control terminal of the intermittent oscillator when the output power monitoring circuit determines that the output voltage and/or current exceeds a reference value. The protection circuit and a photocoupler receiver element are connected in parallel with the control circuit. Where a circuit error occurs and the photocoupler receiver element fails to cycle the intermittent oscillator between active and inactive conditions for a predetermined time, the protection circuit provides a backup which outputs a stop control signal to stop oscillation of the intermittent oscillator element.
    Type: Grant
    Filed: October 15, 2001
    Date of Patent: April 1, 2003
    Assignee: SMK Corporation
    Inventor: Toshihiro Amei
  • Patent number: 6535407
    Abstract: A DC/DC converter is provided that includes a switch device for converting a DC voltage into an AC voltage, a piezoelectric transformer for changing the AC voltage and a current doubler type rectification-smoothing device, which includes a first diode, a second diode, a first inductor, a second inductor, and a capacitor. The piezoelectric transformer has one output terminal connected to a cathode of the first diode and to one terminal of the first inductor, and the other output terminal connected to a cathode of the second diode and to one terminal of the second inductor. Anodes of the first and the second diodes are respectively grounded. The other terminal of the first inductor is connected at a predetermined connection point to the other terminal of the second inductor. The connection point is connected to one terminal of the capacitor, whose other terminal is grounded.
    Type: Grant
    Filed: July 28, 1998
    Date of Patent: March 18, 2003
    Assignee: NEC Corporation
    Inventor: Toshiyuki Zaitsu
  • Patent number: 6529388
    Abstract: In a configuration which is provided with a voltage control circuit 2 for supplying a DC voltage control signal created on the basis of the voltage detecting signal 44 to an terminal of an auxiliary coil L3, wherein the voltage control circuit 2 controls the oscillating amplitude of a transistor Q1 for oscillation using the voltage control signal to stabilize the voltage of the secondary output, and the secondary output is led to a high voltage applying portion of a toner system printing section, a detecting signal creating circuit 5 rectifies the output from the voltage detecting coil L4 at the same timing as the rectifying/smoothing circuit rectifies the output from the secondary coil L2.
    Type: Grant
    Filed: October 5, 2001
    Date of Patent: March 4, 2003
    Assignee: Funai Electric Co., Ltd.
    Inventor: Yoshio Higuchi
  • Patent number: 6525948
    Abstract: The present invention provides a ring choke converter, a kind of power supply, and method thereof. In addition to the transformer, the switch component, the positive feedback circuit and the regulation control circuit in a conventional RCC, the present invention provides a control circuit partially powered by terminal of the opposite polarity at the feedback winding of the transformer. With the circuit design of the control circuits disclosed in this invention, under-voltage protection (UVP), over-voltage protection, and overload protection, together with stable output voltage are all achieved.
    Type: Grant
    Filed: August 29, 2001
    Date of Patent: February 25, 2003
    Assignee: Delta Electronics Inc.
    Inventor: Wen-Kuan Hsu
  • Patent number: 6504733
    Abstract: When a main switching transistor of a zero voltage switching power supply is conductive, a voltage is developed in a current sensing resistor coupled in series with the transistor. The voltage in the current sensing resistor is coupled to a control terminal of a comparator transistor. During a given conduction interval of the main switching transistor, the comparator transistor is turned on when the current sensing resistor voltage is sufficiently large to turn on the comparator transistor. An output of the comparator transistor is coupled to the control terminal of the main switching transistor for controlling the turn off instant of the main switching transistor on a current pulse-by-current pulse basis. A resonant voltage pulse developed at a main current conducting terminal of the main switching transistor is capacitively coupled to the control terminal of the comparator transistor for maintaining the comparator transistor turned on, during a transition interval of the resonant voltage pulse.
    Type: Grant
    Filed: February 27, 2001
    Date of Patent: January 7, 2003
    Assignee: Thomson Licensing S.A.
    Inventors: Robert Goah Watson, III, William Vincent Fitzgerald
  • Patent number: 6501666
    Abstract: This invention provides a method and apparatus for magnetic amplifier to reduce the minimum load requirement of power supply. The apparatus comprises a voltage-dropper and a current-limiter. Through the voltage-dropper and the current-limiter, the master output of the power supply is coupled to the output of magnetic amplifier. The differential voltage of the master output and the magnetic amplifier output decide the voltage of the voltage-dropper. The current-limiter limits the current flows from the master output to magnetic amplifier output. If the master output is no load and the magnetic amplifier is full load condition, a start-up current will flow from the master output to the output of magnetic amplifier via the voltage-dropper and the current-limiter. In the mean time, the start-up current will widen the pulse width of the PWM signal until the current-limiter limits the current. The maximum current of the current-limiter is assigned to maintain the minimum pulse width of the PWM signal.
    Type: Grant
    Filed: August 15, 2001
    Date of Patent: December 31, 2002
    Assignee: System General Corp.
    Inventor: Ta-yung Yang
  • Patent number: 6483725
    Abstract: DC/DC conversion circuit (1), includes a transformer (2) having a primary winding (3), a secondary winding (4), and an auxiliary winding (5); a switching transistor (T), including a series circuit with the primary winding (3) between first and second direct current input terminals (6; 7); a start circuit (R1, C1) connected to a control electrode of the switching transistor (T) for switching the switching transistor (T) on by powering the direct current input terminals (6; 7); a control transistor connected to the control electrode of the switching transistor (T) for switching off the switching transistor (T) in dependence on a current flowing through the series circuit during operation.
    Type: Grant
    Filed: February 1, 2001
    Date of Patent: November 19, 2002
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Cornelis Johannes Adrianus Schetters, Johannus Emmanuel Maria Lammers, Tijmen Cornelis Van Bodegraven
  • Patent number: 6472827
    Abstract: A push-pull inverter is supplied from an inductively current-limited DC voltage source by way of a center-tap on a transformer having significant inductance. This transformer inductance is parallel-coupled with a capacitance means. The inverter is made to self-oscillate through positive feedback provided by way of a saturable current transformer. The inverter frequency is determined by the saturation time of this current transformer, which saturation time is designed to be somewhat longer than the half-cycle period of the natural resonance frequency of the transformer inductance combined with the capacitance means. By controlling the length of this saturation time, the magnitude of the current provided to the fluorescent lamp is controlled, thereby permitting control of the light output in response to changes in the magnitude of the power line voltage.
    Type: Grant
    Filed: March 18, 1993
    Date of Patent: October 29, 2002
    Inventor: Ole K. Nilssen
  • Patent number: 6452817
    Abstract: In an insulating converter transformer of a composite resonance type switching power supply circuit having a secondary active clamp circuit, a primary winding and a secondary winding are wound in a so-called inverse winding style, and connected to each other with additive polarity. In this construction, a primary magnetic flux and a secondary magnetic flux act to offset each other, so that no saturation occurs without forming any gap in the core of the insulating converter transformer.
    Type: Grant
    Filed: October 25, 2001
    Date of Patent: September 17, 2002
    Assignee: Sony Corporation
    Inventor: Masayuki Yasumura
  • Publication number: 20020114173
    Abstract: A switching power supply apparatus comprises a transformer having primary winding and at least two secondary windings, a first switching element connected in series with the primary winding, a control circuit for controlling the output from the first switching element by control of the on-time thereof, a rectification circuit for rectifying at least two outputs from the secondary windings, an output detection circuit for detecting the output voltages and feeding back the output voltages as a control signal for control of the on-time to the control circuit. The output voltage detection circuit comprises a control signal formation section in which the control signal for the on-time is formed, corresponding to a voltage at a voltage comparison terminal, and plural voltage detectors connected between the at least two outputs of the secondary windings and the voltage comparison terminal, respectively.
    Type: Application
    Filed: April 5, 2002
    Publication date: August 22, 2002
    Applicant: Murata Manufacturing, Co., Ltd
    Inventors: Tatsuya Hosotani, Hiroshi Takemura, Takahiro Minagawa
  • Publication number: 20020110003
    Abstract: A switching power supply unit includes first and second switching circuits which alternately turn first and second switching elements on and off with an intermediate period in which both are turned off, and energy is stored in a primary winding of a transformer during an ON period of the first switching element and the energy is discharged from a secondary winding of the transformer during an OFF period of the first switching element. A control circuit includes an OFF period extending circuit connected to a control terminal of the first switching element, such that a transistor remains turned on for a desired period even after the energy has been discharged from the secondary winding, extending the OFF period of the first switching element for the desired period. In a light load operation, a phototransistor in the second control circuit is turned on so that the ON period of the second switching element will be shorter than the time required to discharge the energy from the secondary winding.
    Type: Application
    Filed: December 19, 2001
    Publication date: August 15, 2002
    Applicant: Murata Manufacturing Co., Ltd.
    Inventors: Tatsuya Hosotani, Hiroshi Takemura
  • Patent number: 6414855
    Abstract: A power converter individually comprises a first semiconductor device <2> and a second semiconductor device <3>. In the first semiconductor device <2>, a power conversion element such as an IGBT <19>, Zener diodes <20, 21>, a waveform shaping circuit <30>, a heating cutoff circuit <31> and a protective element <14> are formed on the same chip employing a p-type silicon substrate. In the second semiconductor device <3>, a Schmidt circuit <9>, a power supply circuit <10>, a high voltage detection circuit <11>, a protective element <13>, a logic gate <16> and an output circuit formed by a pnp transistor <17> are formed on the same chip employing a p-type silicon substrate. Thus, a power converter capable of reducing the circuit scale as a whole is obtained.
    Type: Grant
    Filed: April 24, 2001
    Date of Patent: July 2, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Yukio Yasuda
  • Patent number: 6411528
    Abstract: The invention provides a switching power circuit and an insulating converter transformer. A tertiary winding to be formed on the secondary side of an insulating converter transformer is coiled in such a manner as to achieve a state of tight coupling with respect to a primary winding on the primary side of the insulating converter transformer and also to a secondary winding on the secondary side thereof, so that the peak value of a secondary current outputted from a second half-wave rectifying circuit can be reduced by the tertiary winding of the insulating converter transformer.
    Type: Grant
    Filed: September 28, 2000
    Date of Patent: June 25, 2002
    Assignee: Sony Corporation
    Inventor: Masayuki Yasumura
  • Patent number: 6404654
    Abstract: A self-oscillation type resonant flyback converter includes a series combination of a primary winding and a switching transistor. A secondary winding is connected to a power diode and to an output capacitor. A feedback winding is connected to a delay driving circuit comprising a delay diode, a constant-current diode and a capacitor. The delay driving circuit is provided to delay a positive feedback signal from said feedback winding, so that when said power diode becomes non-conducting, said delay diode becomes in the reverse conduction state, starting a free resonance period that concludes when the said delay diode becomes non-conducting and the switching transistor is achieved at zero voltage switching.
    Type: Grant
    Filed: June 26, 2001
    Date of Patent: June 11, 2002
    Inventor: Johnson Wang
  • Publication number: 20020060913
    Abstract: A power converter individually comprises a first semiconductor device <2> and a second semiconductor device <3>. In the first semiconductor device <2>, a power conversion element such as an IGBT <19>, Zener diodes <20, 21>, a waveform shaping circuit <30>, a heating cutoff circuit <31> and a protective element <14> are formed on the same chip employing a p-type silicon substrate. In the second semiconductor device <3>, a Schmidt circuit <9>, a power supply circuit <10>, a high voltage detection circuit <11>, a protective element <13>, a logic gate <16>and an output circuit formed by a pnp transistor <17>are formed on the same chip employing a p-type silicon substrate. Thus, a power converter capable of reducing the circuit scale as a whole is obtained.
    Type: Application
    Filed: April 24, 2001
    Publication date: May 23, 2002
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventor: Yukio Yasuda
  • Patent number: 6370041
    Abstract: Instead of inputting a horizontal deflection output pulse, a resonance voltage outputted from the secondary side of an isolation converter transformer forming a switching power supply circuit of the complex resonance type is inputted to the primary side of a flyback transformer via a series resonant capacitor. Then, a resonance voltage having a substantially sinusoidal waveform generated in the primary winding of the flyback transformer is stepped up thereby providing a high direct-current voltage having a specified high voltage level. Thus, it is possible to improve power conversion efficiency and reduce power loss. Also, by inducing a resonance voltage having a substantially sinusoidal waveform on the secondary side of the flyback transformer, the conduction angle of a rectifier diode is widened, and variation in the high direct-current voltage can be surpressed even when the load is varied.
    Type: Grant
    Filed: July 9, 2001
    Date of Patent: April 9, 2002
    Assignee: Sony Corporation
    Inventor: Masayuki Yasumura
  • Patent number: 6370040
    Abstract: A switching power supply apparatus comprises a transformer having primary winding and at least two secondary windings, a first switching element connected in series with the primary winding, a control circuit for controlling the output from the first switching element by control of the on-time thereof, a rectification circuit for rectifying at least two outputs from the secondary windings, an output detection circuit for detecting the output voltages and feeding back the output voltages as a control signal for control of the on-time to the control circuit. The output voltage detection circuit comprises a control signal formation section in which the control signal for the on-time is formed, corresponding to a voltage at a voltage comparison terminal, and plural voltage detectors connected between the at least two outputs of the secondary windings and the voltage comparison terminal, respectively.
    Type: Grant
    Filed: February 23, 2001
    Date of Patent: April 9, 2002
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Tatsuya Hosotani, Hiroshi Takemura, Takahiro Minagawa
  • Publication number: 20020038795
    Abstract: A voltage from an AC power source is converted into a DC voltage in an input-side rectifier-smoother circuit. The DC voltage is then converted into a high-frequency voltage in an inverter, and the resulting high-frequency voltage is voltage-transformed in a transformer. The voltage-transformed high-frequency voltage is converted into a DC voltage in an output-side rectifier-smoother circuit, which is applied via output terminals to a load. The input-side and output-side rectifier-smoother circuits, the inverter and the transformer are enclosed in a casing having a plastic panel. The output terminal of the apparatus is mounted on the plastic panel.
    Type: Application
    Filed: June 28, 2001
    Publication date: April 4, 2002
    Inventors: Masao Katooka, Toru Arai, Haruo Moriguchi
  • Patent number: 6362984
    Abstract: Transformer driving coils 24 and 25 are added to a DC-DC converter composed of a DC power supply 1, semiconductor switching devices 91 and 92, a transformer 2, rectifiers 81 and 82, a filter capacitor 3, and others, in order to perform a self-oscillating operation. On the other hand, an output-voltage detection and control circuit 6 is used to provide control consisting of both frequency and pulse-width modulation, thus keeping the output voltage constant without the use of any expensive IC circuits or pulse transformers.
    Type: Grant
    Filed: June 8, 2001
    Date of Patent: March 26, 2002
    Assignee: Fuji Electric Co., Ltd.
    Inventor: Masakazu Gekinozu
  • Patent number: 6356466
    Abstract: A multimode switched-mode power supply operates in a first control mode when the output power supplied is lower than a predetermined value, and in a second control mode when the output power supplied is higher than said predetermined value. The switched-mode power supply comprises a series arrangement of a switch (S1) and an inductor (L; Lp), the series arrangement being coupled to receive a DC input voltage (Vin). A control circuit (CC) controls the on and/or off times of the switch (S1) to generate a periodical inductor current (Ip) in the inductor (L; Lp). In the first control mode, a peak value of the inductor current (Ip) is substantially constant, independent of the power supplied. The substantially constant peak value is substantially equal to a peak value of the inductor current (Ip) at an instant when the second control mode is altered into the first control mode.
    Type: Grant
    Filed: September 18, 2000
    Date of Patent: March 12, 2002
    Assignee: U.S. Philips Corporation
    Inventors: Pieter Jan Mark Smidt, Thomas Dürbaum
  • Patent number: 6348779
    Abstract: A DC/DC up/down converter (10), comprising first and second input terminals (20, 21); first and second output terminal (30, 31); a coil (L); first switching means (S1) operatively connected to provide a conduction path from said first input terminal (20) to said coil (L) second switching means (S2) operatively connected to provide a conduction path from said first switching means (S1) and said coil (L) to said second input terminal (21); third switching means (S3) operatively connected to provide a conduction path from said coil (L) to said first output terminal (30); fourth switching means (S4) operatively connected to provide a conduction path from said coil (L) and said third switching means (S3) to said second output terminal (31); control means (11) operatively connected for controlling said switching means (S1, S2, S3, S4); reference voltage means (12) for providing a reference voltage (Vr); and comparator means (13) for providing a comparison signal (Vc) for said control means (11) in response to compa
    Type: Grant
    Filed: August 1, 2000
    Date of Patent: February 19, 2002
    Assignee: U.S. Philips Corporation
    Inventor: Ferdinand Jacob Sluijs
  • Patent number: 6317337
    Abstract: A switching power supply circuit has an insulated converter transformer with a gap for a loose coupling. on the secondary side, a parallel resonant capacitor is connected parallel to a secondary winding, and a full-wave rectification circuit produces a secondary-side DC output voltage for increasing a maximum load power. On the primary side, an ordinary full-wave rectification circuit, rather than a voltage doubler rectifying circuit, inputs a rectified and smoothed voltage having a level corresponding to the level of an AC input voltage. A constant-voltage control circuit system for stabilizing a secondary output voltage varies a switching frequency depending on the level of the secondary output voltage to perform composite control over a resonant impedance of a primary parallel resonant circuit and a conduction angle of the switching element.
    Type: Grant
    Filed: November 7, 2000
    Date of Patent: November 13, 2001
    Assignee: Sony Corporation
    Inventor: Masayuki Yasumura
  • Patent number: 6314004
    Abstract: A switching power source in which the voltage error of a secondary side DC output is fed back to a switching circuit through an insulating element, thereby to stabilize the output voltage. In the switching power source, irrespective of the voltage of the secondary side DC output, a pulse of the level with which an error detecting circuit determines that the voltage of the secondary side DC output has been increased is applied to the error detecting circuit, whereby the switching operation of the switching circuit is changed into an intermittent operation corresponding to the pulse.
    Type: Grant
    Filed: May 11, 1999
    Date of Patent: November 6, 2001
    Assignee: Funai Electric Co. Ltd.
    Inventor: Yoshio Higuchi
  • Patent number: 6295212
    Abstract: A power supply system includes an a-c. power source and an off-line power supply for storing energy from the a-c. power source during first selected time intervals and converting at least a portion of the stored energy to a d-c. output during second selected time intervals. A diode or other switch disconnects the off-line power supply from the a-c. power source during the second selected time intervals to reduce conducted EMI. The first and second selected time intervals are preferably synchronized to the frequency of the a-c. power source.
    Type: Grant
    Filed: January 19, 2000
    Date of Patent: September 25, 2001
    Assignee: Bias Power Technology, Inc.
    Inventors: Kenneth W. Kayser, Kalman Zsamboky, Robert A. Shaufl
  • Patent number: 6295211
    Abstract: A switching power supply unit includes a DC power supply, a transformer having a primary winding, a secondary winding and a feedback winding, a main switching element connected in series to the primary winding, and a control circuit connected between the feedback winding and the control terminal of the main switching element, so that a DC output can be obtained. In this switching power supply unit, there are provided a voltage generating unit disposed on the primary side of the transformer to output a voltage according to a load power, and a delay circuit for reducing the switching frequency by delaying the turn-on of the main switching element according to a voltage output from the voltage generating unit thereby to prolong the OFF time of the main switching element.
    Type: Grant
    Filed: January 11, 2000
    Date of Patent: September 25, 2001
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Akio Nishida, Ryota Tani, Koji Nakahira
  • Patent number: RE37898
    Abstract: Regulation of the output voltage of a power supply employing a flyback-type self-oscillating DC—DC converter employing a transformer. The primary winding circuit of the transformer senses a current recirculation loop for discharging the energy cyclically stored in an auxiliary winding of the self-oscillation loop of the converter such as to represent a replica of the circuit of the secondary winding of the transformer and by summing a signal representative of the level of the energy stored in the auxiliary winding with a drive signal on a control node of a driver of the power switch of the converter.
    Type: Grant
    Filed: December 16, 1999
    Date of Patent: November 5, 2002
    Assignee: STMicroelectronics S.r.l.
    Inventor: Giordano Seragnoli