Abstract: A control circuit of a resonant power converter is disclosed. The control circuit comprises a first transistor and a second transistor for switching a transformer and a resonant tank comprising a capacitor and an inductor. A controller is configured to receive a feedback signal correlated to the output of the power converter for generating a first switching signal and a second switching signal to drive the first transistor and the second transistor, respectively. A diode coupled to the first transistor and the resonant tank for detecting the state of the first transistor and generating a detection signal for the controller. The detection signal indicates if the transistors are in a zero voltage switching (ZVS) state. If the transistors are not in the ZVS state, the switching frequency of the transistors will be increased.

Abstract: A method of controlling a switching mode power converter enables zero voltage switching by forcing a voltage across the main switch to zero. This is accomplished by sensing when a current on the secondary side of the power converter drops to zero, or other threshold value, and then generating a negative current through the secondary winding in response. The negative secondary current results in a corresponding discharge current in the primary winding, which reduces the voltage across the main switch. The voltage across the main switch is monitored such that when the voltage reaches zero, or other threshold value, the main switch is turned ON. In this manner, the circuit functions as a bi-directional current circuit where a forward current delivers energy to a load and a reverse current provides control for reducing the voltage across the main switch to enable zero voltage switching.

Abstract: A current resonance power supply includes a transformer having a primary winding and a secondary winding, two switching elements connected to one end of the primary winding of the transformer and arranged in series, a resonance capacitor connected to the other end of the primary winding, and a voltage detection unit connected between the one end of the primary winding and the two switching elements and configured to detect that AC voltage input to a primary side of the transformer becomes lower, wherein operations of the switching elements are controlled based on a detection result of the voltage detection unit.

Abstract: A power supply apparatus includes an AC-DC rectifier, a transformer, a feedback inductor, a resonant unit, and a primary and auxiliary switch. The AC-DC rectifier rectifies an input voltage. The transformer includes a primary coil having a first primary coil and an isolated second primary coil, and transforms a first voltage of the primary coil into a second voltage of the secondary coil. The feedback inductor is connected to a tap between the first primary coil and second primary coil and an output of the AC-DC rectifier. The resonance unit is connected in parallel with the secondary coil and is configured to output an output voltage by rectifying the second voltage provided from the secondary coil. The primary switch and secondary switch are connected in parallel between the transformer and AC-DC rectifier.

Abstract: The present invention relates to an oscillator that is capable of realizing duty balancing. The oscillator determines a switching frequency of a converter converting an input voltage according to a switching operation of switches to generate an output voltage. The oscillator determines a first half cycle of a duty signal determining the switching frequency by using a reference current according to a feedback signal corresponding to the output voltage. The oscillator senses a first half cycle period by using an output of the frequency setting unit, and determines the same period as the first half cycle as a second half cycle of the duty signal after the first half cycle.

Abstract: A power converter includes a main switch to which a capacitor is connected through a sub-diode. A series connection of a primary coil of a transformer and a sub-switch is connected parallel to the capacitor. A main diode is coupled in series with the main switch. A series connection of a sub-diode and a secondary coil of the transformer is parallel to the main diode. The rate of a rise in voltage across the main switch when turned off is suppressed by the rate of charging of the capacitor. Subsequently, by turning on the sub-switch, the current flowing through the main diode to be delivered to the transformer, thereby causing the current flowing through the main switch when turned on to be decreased by the sub-inductor.

Abstract: An electrical circuit as part of a reduced size power supply with improved use of electrical power can include an isolation circuit between an LC switching circuit and a load, a parallel LC energy storage circuit, and/or a dual LC switching circuit.

Abstract: Disclosed is a high boost ratio DC converter, wherein the first and second switches are controlled by a control chip and the control chip controls the first and second switches in the following sequence: the first and second switches both conduct; the first switch conducts and the second switch is cut off; the first and second switches both conduct; the first switch is cut off and the second switch conducts thus making a first and second inductors and a first and second clamp capacitors charge to a first and second output capacitors. Then the first and second output capacitors discharge a load. Therefore, the load voltage output from the DC power supply will be boosted owing to the discharged load from the first and second output capacitors. The boost ratio is 4/(1?D).

Abstract: Power supplies, power adapters, and related methods are disclosed. One example power supply includes an open loop DC to DC converter having an input for connecting to an input power source and an output for supplying a DC output voltage or current and an enable/disable circuit coupled to the open loop DC to DC converter. The enable/disable circuit is configured to enable and disable the open loop DC to DC converter as a function of the DC output voltage or current. One example method includes determining a DC output voltage or current from an open loop DC to DC converter and enabling and disabling the open loop DC to DC converter as a function of the determined DC output voltage or current.

Abstract: A high voltage power supply is provided. The high voltage power supply includes an inverter which converts a DC voltage input to the high voltage power supply into a first AC voltage, a transformer including an input winding unit and a plurality of output winding units, wherein the input winding unit receives the first AC voltage from the inverter and the plurality of output winding units generates and outputs a second AC voltage, and a voltage multiplier unit which boosts the second AC voltage output by the transformer and outputs a boosted voltage, and the voltage multiplier unit includes a plurality of voltage multipliers which are connected to each other in series and the plurality of voltage multipliers may be connected to the plurality of output winding units respectively.

Abstract: Methods, systems, and devices are described for both power and control signal transmission through a single coupled inductor. A current driver generates a cyclical current signal on a primary winding of a coupled inductor, to induce a voltage signal at the secondary winding corresponding to the cyclical current signal. A rectifier module is coupled with the secondary winding and configured to rectify the signal induced at the secondary winding. A control timing signal module is coupled with the primary winding and configured to induce voltage pulses on the secondary winding, the induced voltage pulses having an insubstantial impact on the output of the rectifier module. A switching module coupled with the secondary winding is configured to receive the voltage pulses and control a switching signal for a power switch coupled with the output of the rectifier and provide power to a load coupled with the output of the rectifier.

Abstract: This inverter circuit includes first and second switching elements and an output transformer which is provided with a first primary winding connected in series between said first and second switching elements, and also with a secondary winding for obtaining an output voltage. The inverter circuit is further provided with a first voltage supply, a second voltage supply, and a control unit. The first voltage supply applies voltage to said first switching element via said first primary winding. And the second voltage supply applies voltage to said second switching element via said second primary winding. The control unit turns said first switching element and said second switching element alternatingly ON and OFF. This inverter circuit also includes first and second regeneration snubber circuits for regenerating the charge charged into snubber capacitors.

Abstract: A phase-controlled power supply is disclosed. The power supply includes a power conditioner with an input configured to connect to an external source of electrical power, the power conditioner being configured to provide conditioned power on its output. The power supply also includes a transformer having a primary winding and a secondary winding, and a switching module coupled between the output of the power conditioner and to the primary winding of the transformer. The switching module has two modes of operation and a control signal input configured to accept a first control signal. The switching module includes a switching element configured to connect the power conditioner output to the primary winding of the transformer. The switching module operates in the first mode when the first control signal is in a first state, switching the first switching element at a first frequency and first duty cycle.

Abstract: An inverter drive power supply circuit for driving a plurality of inverter switching devices that form an inverter circuit, includes a number N of transformers (N is an integer equal to or larger than 2) adapted to a push-pull method, each having a first winding and a second winding for a primary winding and a first winding and a second winding for a secondary winding, and supplying an output voltage of the secondary winding to the inverter switching devices.

Abstract: This DC-DC converter circuit includes: first and second switching elements (S1, S2); an output transformer (T) that includes a first primary winding (P1) connected in series between the positive electrode sides of the first and second switching elements (S1, S2), a second primary winding (P2) connected in series between their negative electrode sides, a secondary winding (S) for obtaining an output voltage, and tertiary windings (n3, n4); a first voltage source (C1), connected between a first connection point at which the first primary winding (P1) is connected to the second switching element (S2) and the first switching element (S1), that applies a voltage to the first switching element via the first primary winding; a second voltage source (C2) connected to locations symmetric with those of the first voltage source (C1); and a control unit (CT) that turns the first and second switching elements (S1, S2) alternatingly ON and OFF, and first and second regeneration snubber circuits (SN1, SN2) for regenerating

Abstract: An adaptive inductive ballast is provided with the capability to communicate with a remote device powered by the ballast. To improve the operation of the ballast, the ballast changes its operating characteristics based upon information received from the remote device. Further, the ballast may provide a path for the remote device to communicate with device other than the adaptive inductive ballast.

Abstract: An adaptive inductive ballast is provided with the capability to communicate with a remote device powered by the ballast. To improve the operation of the ballast, the ballast changes its operating characteristics based upon information received from the remote device. Further, the ballast may provide a path for the remote device to communicate with device other than the adaptive inductive ballast.

Abstract: An adaptive inductive ballast is provided with the capability to communicate with a remote device powered by the ballast. To improve the operation of the ballast, the ballast changes its operating characteristics based upon information received from the remote device. Further, the ballast may provide a path for the remote device to communicate with device other than the adaptive inductive ballast.

Abstract: A method of operating a resonant power converter(1, 2), having a high side switch(3) and a low side switch(4), is disclosed in which the switching is controlled to allow for improved operation at low power levels. The method involved an interruption to the part of the switching cycle in which the low side switch (4) is normally closed, by opening the switch at a particular moment in the cycle which allows the energy to be store in the resonance capacitor (5). Since, as a result, the energy is largely not resonating but stored in a single component, the time quantization of the mode of operation is significantly reduced or eliminated.

Abstract: The invention discloses a control circuit for an AC-DC converter. The control circuit includes a power control circuit for comparing an input current sensing signal generated by sensing an input current of the AC-DC converter and a power level control input and in response thereto generating a frequency modulation control signal, in which the frequency modulation control signal is used to control the output power of the AC-DC converter and suppress harmonics of the input current, and a square wave generator connected to the power control circuit for generating a driving signal used to drive the switch circuit of the AC-DC converter according to the frequency modulation control signal, in which the frequency of the driving signal is varied with the frequency modulation control signal, thereby suppressing harmonics of the input current and regulating the switching frequency the AC-DC converter, and regulating the output power of the AC-DC converter.

Abstract: A technique for suppressing lowering of withstand voltage and lowering of breakdown resistance and reducing a feedback capacitance of a power MISFET is provided. A lateral power MISFET that comprises a trench region whose insulating layer is formed shallower than an HV-Nwell layer is provided in the HV-Nwell layer (drift region) formed on a main surface of a semiconductor substrate in a direction from the main surface to the inside. The lateral power MISFET has an arrangement on a plane of the main surface including a source layer (source region) and a drain layer (drain region) arranged at opposite sides to each other across a gate electrode (first conducting layer), and a dummy gate electrode (second conducting layer) that is different from the gate electrode is arranged between the gate electrode and the drain layer.

Abstract: An adaptive inductive ballast is provided with the capability to communicate with a remote device powered by the ballast. To improve the operation of the ballast, the ballast changes its operating characteristics based upon information received from the remote device. Further, the ballast may provide a path for the remote device to communicate with device other than the adaptive inductive ballast.

Abstract: An adaptive inductive ballast is provided with the capability to communicate with a remote device powered by the ballast. To improve the operation of the ballast, the ballast changes its operating characteristics based upon information received from the remote device. Further, the ballast may provide a path for the remote device to communicate with device other than the adaptive inductive ballast.

Abstract: An adaptive inductive ballast is provided with the capability to communicate with a remote device powered by the ballast. To improve the operation of the ballast, the ballast changes its operating characteristics based upon information received from the remote device. Further, the ballast may provide a path for the remote device to communicate with device other than the adaptive inductive ballast.

Abstract: An output apparatus includes a first source of a first signal having a first state or a different second state; a second source of a second signal having a first state or a different second state; and a circuit structured to output a vital output including a first state when the first state of the first signal corresponds to the first state of the second signal and, otherwise, including a different second state. At least one of the first signal and the second signal is a static signal. The other one of the first signal having the first state and the second signal having the first state is a dynamic signal. When at least one of the first signal has the different second state of the first signal and the second signal has the different second state of the second signal, the vital output includes the different second state.

Abstract: Magnetically induced control signals into a transistorized switching circuit that drives an efficient output transformer provides high frequency control to power circuits with low RFI. Improved co-axial transformer embodiments s and co-axial lead acid battery embodiments are also provided.

Abstract: In order to further develop a circuit arrangement (100) as well as a method for generating at least one drive signal for at least one synchronous rectification switch of at least one flyback converter in such way that an improved and simpler thermal management can be combined with a significant cost reduction as well as with a higher efficiency, it is proposed to generate the drive signal for said synchronous rectification switch as a function of at least one oscillating signal controlling the synchronous rectification switch, of at least one constant delay time, of at least one variable delay time, and of at least one Boolean OR function.

Abstract: A light-emitting keyboard is disclosed, which comprises: a light guide plate, configured with a light entrance surface, a light emitting surface and a via hole; a light source, disposed next to the light entrance surface of the light guide plate; a frame, disposed on the light emitting surface of the light guide plate; an opaque material disposed on the via hole. With the aforesaid structure, light from the light source can be prevented from being emitting out from the via hole and thus can be evenly emitted out of the light guide plate.

Abstract: A magnetic integration double-ended converter with an integrated function of a transformer and an inductor includes an integrated magnetic member having a magnetic core with three magnetic columns having at least three windings (NP, NS1, NS2) and at least one energy storage air gap, where a primary winding (NP) and a first secondary winding (NS1) are both wound around a first magnetic column or are both wound around a second magnetic column and a third magnetic column, and a second secondary winding (NS2) is wound around the second magnetic column; an inverter circuit with double ends symmetrically working, acting on the primary winding (NP); and a group of synchronous rectifiers (SR1, SR2), gate electrode driving signals of which and gate electrode driving signals of a group of power switch diodes (S1, S2) of the inverter circuit with the double ends symmetrically working complement each other.

Abstract: A three-phase power supply with a three-phase three-level DC/DC converter includes a full-bridge thyristor converter with three-set four in-series power switch elements, a three-phase isolated transformer, a full-bridge rectifier, a rectifying circuit, and a low-pass filtering circuit. The three-phase power supply is used to deliver power energy from the AC input voltage to the load. The power switch elements, which separated to each other at 120-degree phase differences, are controlled through a phase shift scheme. Therefore, the three-level circuit structure is provided to reduce withstanding voltage of the power switch elements, further the zero-voltage switching (ZVS) is achieved by the isolated transformer and the power switch elements to increase the efficiency of the DC/DC converter.

Abstract: The present invention is a new circuit topology to improve the efficiency of a flyback or push-pull converter or any other DC/DC converter that incorporates a transformer and whose switching device's active node (drain for MOSFETs and collector for IGBTs) has no direct energy releasing path to the power supply. The present invention uses an auxiliary DC/DC converter separate from the main DC/DC converter to reroute the parasitic energy stored in the transformer's or inductor's leakage inductance, allowing for the output of the main DC/DC converter to be augmented with the energy that would otherwise be lost. The energy stored in the leakage inductance is converted and redirected to either the load side or the power supply side of the main DC/DC converter in a series or a parallel configuration. The present invention significantly increases the overall efficiency of the system by eliminating the power loss.

Abstract: The objective of the present invention is to provide a power converter capable of not only boosting the voltage but also shutting-off the flowing current, by switching only the switch element. The power converter 1, comprises a first input-output portion 3, a second input-output portion 5, a first capacitor C1, a second capacitor C2 electrically connected with the first capacitor C1 in serial, a first current control block B1, a second current control block B2, a third current control block B3, a fourth current control block B4, and a switching controller 7 operable to switch certain current control blocks, wherein the current flowing direction is opposite to each other between a first current control element B1a (B2a, B3a, B4a) and a second current control element B1b (B2b, B3b, B4b) which compose the current control block B1 (B2, B3, B4).

Abstract: An adaptive inductive ballast is provided with the capability to communicate with a remote device powered by the ballast. To improve the operation of the ballast, the ballast changes its operating characteristics based upon information received from the remote device. Further, the ballast may provide a path for the remote device to communicate with device other than the adaptive inductive ballast.

Abstract: This inverter circuit includes two switching elements which are turned alternately ON and OFF, and a first primary winding connected in series between these switching elements, and also includes an output transformer having a secondary winding for obtaining an output voltage. This inverter circuit also includes a first voltage source and a second voltage source. The first voltage source applies a voltage to the first switching element via the first primary winding. And the second voltage source applies a voltage to the second switching element via the second primary winding. This inverter circuit also includes a regeneration snubber circuit for regenerating charge accumulated in a snubber capacitor. The regeneration snubber circuit includes a regeneration circuit including a voltage boost section which converts the primary side voltage of the output transformer to a predetermined voltage, which it outputs.

Abstract: Provided is a transformer, comprising a first winding and a second winding that interlink with a main magnetic flux; and a third winding that interlinks with a magnetic flux leakage interlinking with only one of the first winding and the second winding.

Abstract: A method for determining a primary side voltage of a distribution transformer includes determining a first current and a second current flowing through a secondary winding of the transformer at a plurality of time instants based on current meter data generated by a plurality of metered loads. The method may include determining a total current flowing to the plurality of metered loads for each of the plurality of time instants based on the first current and the second current. The method includes receiving a respective meter voltage from each of the plurality of metered loads at each of the plurality of time instants. The method includes determining a secondary side voltage of the transformer at each of the plurality of time instants based on the first, second, and total current and the respective meter voltages. The method includes determining the primary side voltage based on the secondary side voltage.

Abstract: This inverter circuit includes first and second switching elements and an output transformer which has a first primary winding connected in series between the first switching element and the second switching element and a second primary winding for obtaining an output voltage. The inverter circuit also includes a first voltage source, a second voltage source, and a control unit. The first voltage source is connected between a first connection point at which the first primary winding is connected to the second switching element, and the first switching element, and applies a voltage to the first switching element via the first primary winding. And the second voltage source is connected between a second connection point at which the first primary winding is connected to the first switching element, and the second switching element, and applies a voltage to the second switching element via the first primary winding.

Abstract: This current balanced push-pull type inverter circuit includes first and second switching elements, and an output transformer which includes a first primary winding and a second primary winding connected in series between said first and second switching elements, and also includes a secondary winding for obtaining an output voltage. This inverter circuit also includes a first voltage supply capacitor, a second voltage supply capacitor, and a control unit. A first snubber circuit, in which a first free wheel diode and first and second snubber capacitors are connected in series, is connected in inverse parallel to the first switching element. A first discharge resistor is connected between the first snubber capacitor and a first power supply capacitor, and a second discharge resistor is connected between the second snubber capacitor and a third power supply capacitor. And a second snubber circuit and discharge resistors are connected to the second switching element as well, in a similar manner.

Abstract: A resonant, bi-directional, DC to DC voltage converter with loss-less (soft) switching having regulated output and capable of converting power between two, high-potential and low-potential DC voltage sources. The converter's semiconductor and magnetic components provide both, output regulation and soft switching in both (step-down and step-up) directions of power conversion which reduces total component count, cost and volume and enhances power conversion efficiency.

Abstract: A heating device for an inductive cooking device is provided and includes a first resonant circuit, with at least one first and one second inductor, for the transmission of heat energy to a heating element for heating thereof and a first circuit for energising the first resonant circuit and introduction of the heat energy to the inductors. Differing cooking containers may be effectively heated, whereby the heating device has a switching device by which the heating energy is selectively supplied to only one of the inductors or simultaneously to both inductors in a parallel circuit.

Abstract: A switching power supply exhibits high conversion efficiency and facilitates reducing the size thereof. The switching power supply includes a half-bridge circuit including a first series circuit formed of switching devices Q1 and Q2 and connected between the output terminals of a DC power supply; and a second series circuit connecting primary inductance Lr1 of transformer T1, primary inductance Lr2 of transformer T2 and capacitor Cr in series. The second series circuit is connected between the output terminals of the half-bridge circuit, and is made to conduct a series resonance operation. The switching devices Q1 and Q2 is controlled at the ON-duties of 0.5 for reducing the breakdown voltages of rectifying diodes D1 and D2 on the secondary side of transformers T1 and T2 and for improving the conversion efficiency of the switching device.

Abstract: A pulsed drive signal without a dead band can be achieved by a drive circuit arranged to receive opposite pulsed input signals (PWM drive A, PWM drive B), having a dead band between them,—a transformer arranged to receive the input signals (PWM drive A, PWM drive B) and output intermediary signals (A?, B?),—time delay circuitry (RA, DA, RB, DB) arranged to receive the intermediary signals, and to provide buffer input signals (A?, B?), corresponding to the intermediary signals, but with a ramped up transition from low to high signal,—a first and a second buffer stage arranged to receive the first and second buffer input signals, respectively, and produce the first and the second drive output signal corresponding to the first and second pulsed input signal but with the transition from high to low signal delayed to reduce the dead band.

Abstract: An adaptive inductive ballast is provided with the capability to communicate with a remote device powered by the ballast. To improve the operation of the ballast, the ballast changes its operating characteristics based upon information received from the remote device. Further, the ballast may provide a path for the remote device to communicate with device other than the adaptive inductive ballast.

Abstract: A switching inverter having two single-ended EF2 inverter sections coupled together with a shared ground and partially shared tunable resonant network that is coupled to at least one load, wherein each inverter section comprises a switching section, and wherein the shared tunable network section allows independent tuning of an impedance seen by the corresponding switching section thereby independently tuning even and odd harmonics of the switching frequency.

Abstract: A comparing circuit and a control loop are used to maintain the peak level of current flowing through an inductor of a flyback converter. An inductor switch control signal controls an inductor switch through which the inductor current flows. The inductor current increases at a ramp-up rate during a ramp time and stops increasing at the end of the ramp time. The comparing circuit generates a timing signal that indicates a target time at which the inductor current would reach a predetermined current limit if the inductor current continued to increase at the ramp-up rate. The control loop then receives the timing signal and compares the target time to the end of the ramp time. The pulse width of the inductor switch control signal is increased when the target time occurs after the end of the ramp time. Adjusting the pulse width controls the peak of the inductor current.

Abstract: A switching inverter having two single-ended EF2 inverter sections coupled together with a shared ground and partially shared tunable resonant network that is coupled to at least one load, wherein each inverter section comprises a switching section, and wherein the shared tunable network section allows independent tuning of an impedance seen by the corresponding switching section thereby independently tuning even and odd harmonics of the switching frequency.

Abstract: A DC power source voltage is supplied to a center tap of a primary winding, and first and second semiconductor switches alternately turned on are disposed between each of both ends of the primary winding and a common potential point, and a current flowing through a load is fed back and PWM control of each of the semiconductor switches is performed. Also, snubber circuits are respectively connected between a ground and the center tap of the primary winding, and an abnormal high voltage at the time of switching is reduced. Also, a parallel running of plural inverters is simply performed by disposing PWM comparators corresponding to the first and second semiconductor switches.

Abstract: An AC power supply system modulates a high frequency switching signal with a pulse width modulation (PWM) signal to produce a composite signal. The duty cycle of the PWM component of the composite signal is used to control the brightness of a cold cathode fluorescent lamp for backlighting a liquid crystal display.

Abstract: Generally, a DC/DC converter and its associated devices and processes are presented herein. The DC/DC converter may be a switched mode converter that includes a plurality of switching devices that couple between the first and second power supply rails. A transformer is coupled to the switching devices such that the switching devices exchange electrical energy through the transformer. A rectifier is coupled to the transformer to rectify the waveform from the transformer into a substantially DC output. The DC/DC converter also includes clamp diodes to relieve voltage stress on rectifier diodes. Resistors may be coupled in series with the clamp diodes to reduce a reset time of the DC/DC converter and thereby prevent catastrophic failure of the power supply during load transients. Additionally, the DC/DC converter may be configured with a power outage detection device that monitors gate drive signals of the converter.

Abstract: A power converter for converting an input voltage (Vin) into an output voltage (Vout), comprising a first supply potential and a second supply potential established by the input voltage, and at least one primary winding having two terminals, a center tap arranged between the two terminals and connected to the first supply potential, and at least one secondary winding magnetically coupled to the primary winding for providing at least one output voltage (Vout) and a first controllable switch connected between the second supply potential and one terminal of the primary winding and a second controllable switch connected between the second supply potential and the other terminal of the primary winding and a third controllable switch connected between the second supply potential and the one terminal of the primary winding and a fourth controllable switch connected between the second supply potential and the other terminal of the primary winding, and a control unit for controlling the switches such that the first, s