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Single-ended, separately-driven type

Subclass of:

363 - Electric power conversion systems

363013000 - CURRENT CONVERSION

363015000 - Including D.C.-A.C.-D.C. converter

363016000 - Having transistorized inverter

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Class / Patent application numberDescriptionNumber of patent applications / Date published
363210010 With automatic control of the magnitude of output voltage or current 870
Entries
DocumentTitleDate
20100073966FORWARD CONVERTER TRANSFORMER SATURATION PREVENTION - A control circuit for use in a power converter in one aspect limits the magnetic flux in a transformer of a switching power converter. A first controlled current source has a first current that is substantially directly proportional to an input voltage to be applied to a winding of the transformer. A second controlled current source has a second current that is substantially directly proportional to a reset voltage to be applied to the winding of the transformer. A first switch is adapted to charge an integrating capacitor with the first current while the input voltage is applied to the winding of the transformer. A second switch is adapted to discharge the integrating capacitor with the second current when the reset voltage is applied to the winding of the transformer. A third switch is adapted to remove and to prevent application of the input voltage to the winding of the transformer.03-25-2010
20130077353FAST STARTUP SWITCHING CONVERTER AND METHOD THEREOF - A fast startup switching converter comprises a first switch, a second switch, a third switch, a first capacitor, and a controller controlling the ON and OFF switching of the second and third switches. The first terminal of the first switch is coupled to the input terminal of the switching converter, the second terminal is coupled to the first terminal of the second switch. The first terminal of the third switch is coupled to the second terminal of the first switch and the first terminal of the second switch. The first capacitor is coupled to the second terminal of the third switch and the controller to provide a power supply voltage for the controller. The switching converter charges the first capacitor through the first and third switches in a first working state, and transfers energy to a load through the first and second switches in a second working state.03-28-2013
20100110733Self-Coupled Driver Used In Dual-Switch Forward Power Converter - A dual-switch forward power converter, and a method of operating the same, employs a self-coupled driver to achieve among other advantages higher efficiency, lower part count and component cost. In one aspect of the present invention, a power converter comprises a transformer and two switching transistors, and said transformer has two serially-connected primary windings with the first winding connected to a first switching transistor which is biased by a pulse controller, and the second winding couples the voltage across said first winding to bias the second switching transistor. In addition, the circuit on the primary side of said transformer further comprises means of dissipating magnetization current and the circuit on the secondary side comprises a rectifier and a low-pass filter.05-06-2010
20100135047High-Voltage Modulator System - A high-power modulation system includes drive circuitry that receives input signals from the signal source via a series of transformers. The drive circuitry amplifies the input signals and provides the resulting amplified signals to the high-power switch. The switch includes a series of stacked switching elements, each with a control terminal, first and second current-handling terminals, and feedback path extending between the first current-handling terminal and the control terminal. The feedback paths work in concert to turn the switches on and off together to prevent excessive voltage from developing across one or a subset of the switching elements. The feedback path includes a resistor that dampens the bandwidth of the feedback path to reduce turn-off and turn-on ringing and oscillation. The damping resistor may be coupled in series with a diode that holds charge against the control terminal of the switching element.06-03-2010
20090303754 SWITCHING MODE POWER SUPPLY AND A METHOD OF OPERATING THE POWER SUPPLY IN A POWER SAVE MODE - A switching mode power supply and a method of operating the power supply in a power save mode. The switching mode power supply includes a first PWM controller and a second PWM controller that are driven by different driving voltages and control first and the second voltages to be output, respectively, a first transformer that is controlled by the first PWM controller to output the first voltage and having a primary coil, a secondary coil to induce the first voltage, and an auxiliary winding, and a rectifier that rectifies and smoothes a current flowing through the auxiliary winding of the first transformer, generates a power save mode voltage based on the respective driving voltages of the first and the second PWM controllers, and supplies the power save mode voltage to the first and the second PWM controllers. Accordingly, the power save mode is operated using a voltage difference without requiring an extra controller.12-10-2009
20130063984DEAD-TIME OPTIMIZATION OF DC-DC CONVERTERS - Representative implementations of devices and techniques determine the timing of switches associated with a dc-dc converter. The determination is based on a body diode conduction of at least one of the switches, which is detected and used to determine a switching delay.03-14-2013
20130163289POWER SWITCHING DRIVING APPARATUS, AND POWER FACTOR CORRECTION DEVICE AND POWER SUPPLY DEVICE HAVING THE SAME - There are provided a power switching driving apparatus able to reduce a circuit area and increase a driving speed, and a power factor correction device and a power supply device having the same. The power switching driving apparatus includes: a first driving unit providing a switching signal in response to a control signal from the outside; a second driving unit including first and second NMOS FETs cascode-connected between an operational power source terminal supplying pre-set operation power and a ground, and performing switching complimentarily in response to the switching signal to provide a switching control signal controlling power switching; a current supply unit supplying a current for driving the second driving unit; and a voltage maintaining unit maintaining a voltage for driving the second driving unit.06-27-2013
20120014140SYSTEMS AND METHODS FOR REDUCING TRANSIENT VOLTAGE SPIKES IN MATRIX CONVERTERS - Systems and methods are provided for delivering energy using an energy conversion module that includes one or more switching elements. An exemplary electrical system comprises a DC interface, an AC interface, an isolation module, a first conversion module between the DC interface and the isolation module, and a second conversion module between the AC interface and the isolation module. A control module is configured to operate the first conversion module to provide an injection current to the second conversion module to reduce a magnitude of a current through a switching element of the second conversion module before opening the switching element.01-19-2012
20100033994CONTROL ARRANGEMENT AND CIRCUIT ARRANGEMENT FOR CONVERTING A DC VOLTAGE INTO A RECTIFIED VOLTAGE - Circuitry includes an acquiring circuit to acquire period and phase information of an oscillation. The acquiring circuit includes a first input electrically coupled to a first connection and a second input electrically coupled to a second connection. The first connection and the second connection are for electrically coupling to an oscillating circuit. A control circuit includes a first input electrically coupled to an output of the acquiring circuit. The control circuit includes a second input electrically coupled to a third connection for supply of a voltage that is based on the rectified voltage. A switch includes a controlled segment for electrically coupling a fourth connection to a reference potential connection, and a control connection that is electrically coupled to an output of the control circuit to excite an oscillation in the oscillating circuit via a DC voltage.02-11-2010
20100085778INDUCTANCE ELEMENT, METHOD FOR MANUFACTURING THE SAME, AND SWITCHING POWER SUPPLY USING THE SAME - An inductance element (04-08-2010
20090073726Current Waveform Construction to Generate AC Power With Low Harmonic Distortion From Localized Energy Sources - Methods and apparatus to provide low harmonic distortion AC power for distribution by converting energy from natural or renewable sources into electrical form, and constructing a current waveform on a primary winding of a transformer by recapturing inductive energy previously stored in the transformer so as to transform the converted electrical energy into substantially sinusoidal AC voltage at a secondary winding of the transformer. For example, AC power may be supplied to a utility power grid from raw electrical energy from renewable energy sources (e.g., solar cells). An inverter may construct the primary winding current waveform using two unidirectional switches. On each half cycle, one of the switches first applies energy previously recaptured from primary winding inductance, and then applies the raw energy to the transformer primary winding at the utility power grid frequency. Accordingly, the constructed primary winding current may exhibit substantially improved total harmonic distortion.03-19-2009
20090262558Switching power supply circuit and driving method thereof - A switching power supply circuit includes a direct current (DC) power supply input, a first transistor, a capacitor, a first resistor, a second resistor, a switching circuit including a second transistor, and a first transformer including a first primary winding and a secondary winding. The DC power supply input is connected to a drain electrode of the first transistor via the capacitor. A gate electrode of the first transistor is connected to ground via the first resistor, and connected to the drain electrode of the first transistor via the second resistor. The DC power supply input is connected to a source electrode of the first transistor via the primary winding. The source electrode of the first transistor is grounded via the second transistor. The secondary winding is structured and arranged to drive a load circuit.10-22-2009
20100061122DC-DC CONVERTER - A small and efficient DC-DC converter is provided. In this DC-DC converter, passive elements such as an inductor and a capacitor can be reduced in size by reducing switching loss by a soft switching technology and increasing the drive frequency of a switching element. The DC-DC converter has a main switching element, a main diode and an auxiliary circuit that discharges the electric charges of the capacitance between the ends of the main switching element. The DC-DC converter includes an auxiliary inductor magnetically coupled with the main inductor, an auxiliary switching element that stores energy in the auxiliary inductor, and an auxiliary diode that discharges energy stored in the auxiliary inductor to the direct-current power source or the output side. The auxiliary inductor is coupled with the main inductor in the direction in which backward voltage is applied to the auxiliary diode when the main inductor discharges energy.03-11-2010
20080239759DC/DC CONVERTER - Primary and secondary coils are provided in the first through section and a coil group is also provided in the second through section. Hence, the surface area over which the coil group extends within a plane which is perpendicular to the through sections is greater than in the case where all of the coils are provided in a single through section. The surface area which is not covered by the magnetic body cores of the platelike members increases. In cases where the surface area of the members is large, the heat radiation characteristic is enhanced. Hence, the cooling efficiency of the transformer improves. In cases where there is a plurality of coil groups which are magnetically coupled to one another in particular, because it is difficult to move the heat produced in the plurality of coil groups through heat conduction, heat transfer, or heat radiation, a heat radiation structure of this kind is effective.10-02-2008
20080247195DC/DC CONVERTER - According to the switching supply such as a DC/DC converter, since primary side coils provided in two transformers are mutually connected in series, voltage variation generated in parallel-connected secondary side coils can be suppressed, and the uniformity of secondary side parallel output can be enhanced even in case of voltage value fluctuations or the like caused by variation in the output of an inverter circuit.10-09-2008
20120069604COMPACT POWER CONVERTER WITH HIGH EFFICIENCY IN OPERATION - A power converter including a main circuit and a sub-circuit. The main circuit serves as a step-up/down chopper circuit including a series-connected assembly of main switches, an inductor coupled to a joint of the main switches, and a capacitor connected in parallel to the series-connected assembly. The sub-circuit is designed to establish the soft-switching and includes a snubber capacitor, a first sub-switch coupled to the joint of the series-connected assembly and a negative terminal of the snubber capacitor, a second sub-switch coupled to the joint and a positive terminal of the snubber capacitor, a third sub-switch coupled to the positive terminal of the snubber capacitor and a high-potential terminal of the main circuit, and a fourth sub-switch coupled to the negative terminal of the snubber capacitor and a low-potential terminal of the main circuit.03-22-2012
20090080222System and Method for Power Saving Conversion Topology in Switch Mode Power Supplies - 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.03-26-2009
20090231886POWER SUPPLY AND BOOTSTRAP CIRCUIT THEREOF - A power supply and a bootstrap circuit thereof are provided. The bootstrap circuit includes a transistor, a first capacitor, a first impedance and a regulator circuit. The collector and the emitter of the transistor respectively serve as the input terminal and the output terminal of the bootstrap circuit. A terminal of the first capacitor is coupled to the collector of the transistor. A terminal of the first impedance is coupled to another terminal of the first capacitor. The regulator circuit is coupled to another terminal of the first impedance and the base of the transistor for clamping the voltage of the above-mentioned base at a predetermined voltage level.09-17-2009
20090016083SECONDARY SIDE SYNCHRONOUS RECTIFIER FOR RESONANT CONVERTER - A resonant converter including a primary side switching stage having high- and low-side switches series connected at a switching node and controlled by a primary side controller; a transformer having a primary coil and a secondary coil, the secondary coil having at least one pair of portions series connected at a node, a resonant tank formed by series connecting the primary coil to the switching node with a first inductor and a first capacitor; at least one pair of first and second secondary side switches connected to the at least one pair of portions, respectively, the first and second secondary side switches of each pair being used for synchronous rectification; and a secondary side controller to control and drive the first and second secondary side switches of each pair by sensing voltage across each secondary side switch and determining a turn ON and turn OFF transition for the first and second secondary side switches in close proximity to a point in time when there is zero current through the secondary side switch to achieve synchronous rectification.01-15-2009
20110222315CURRENT-SHARING POWER SUPPLY APPARATUS - A current-sharing power supply apparatus is applied to regulate voltage level of an input DC voltage, and the regulated DC voltage is stabilized in a predetermined voltage to be used on rear-end circuits. The current-sharing power supply apparatus includes a square-wave generating circuit, a rectifier circuit, a conversion circuit, a rectifier circuit, a filter circuit, a first output terminal, and a second output terminal. The current-sharing power supply apparatus provides two output voltages with a multiple relation from the first output terminal and the second output terminal, respectively.09-15-2011
20090257249SEMICONDUCTOR DEVICE, AND ENERGY TRANSMISSION DEVICE USING THE SAME - An energy transmission device includes: a semiconductor device formed on a first semiconductor substrate; a semiconductor integrated circuit including a reverse current preventing diode and a control circuit; a DC voltage source; and a transformer. The reverse current preventing diode includes a reverse current preventing layer of a second conductivity type formed at a surface of a second semiconductor substrate, and a well layer of a first conductivity type formed in the second semiconductor substrate and covering the reverse current preventing layer. The transformer includes a primary winding connected in series with the semiconductor device and the DC voltage source, and a first secondary winding connected to a load. The energy transmission device is configured so that electric power is supplied from the first secondary winding of the transformer to the load. A second drain electrode of the semiconductor device is electrically connected to the reverse current preventing layer.10-15-2009
20090257248DIRECT CURRENT/DIRECT CURRENT CONVERTER WITH MULTIPLE OUTPUTS - In a DC/DC converter comprising a transformer (10-15-2009
20100149838Power System with Power Converters Having an Adaptive Controller - A power system having a power converter with an adaptive controller. In one embodiment, a power converter coupled to a load includes a power switch configured to conduct for a duty cycle to provide an output characteristic at an output thereof. The power converter also includes a power converter controller configured to receive a signal from the load indicating a system operational state of the load and enable a power converter topological state as a function of the signal.06-17-2010
20100195352POWER SUPPLY APPARATUS - The power supply apparatus includes a first control part that controls a switching operation of a first converter, a second control part that controls a switching operation of a second converter, a zero crossing circuit that outputs a zero crossing signal of a voltage to be input; and a voltage supply part that supplies a DC voltage obtained by rectifying an output of an auxiliary coil of a transformer of the first converter to the first control part, the second control part, and the zero crossing circuit. When the first converter stops, the supply of the DC voltage to the second control part and the zero crossing circuit is stopped to reduce a power consumption.08-05-2010
20100226149POWER-SUPPLY CONTROL DEVICE AND POWER-SUPPLY APPARATUS THEREWITH - An embodiment of the invention provides a converter power-supply apparatus that is efficiently operable for a wide-range load. A power-supply control device controls a boost converter. The boost converter includes a basic switching circuit, an expansion switching circuit that is connected in parallel with the basic switching circuit. A control circuit supplies a control signal to the basic and the expansion switching circuit through a first and a second signal line, respectively. A detecting unit detects a voltage and/or a current in a predetermined point of the boost converter. A comparison circuit compares a detected value with a reference value and supplies a first signal when a load is relatively heavy, a second signal when the load is relatively light. A control signal switch connects the second signal line when receiving the first signal, and disconnects the second signal line when receiving the second signal.09-09-2010
20100302810VOLTAGE CONVERTERS WITH INTEGRATED LOW POWER LEAKER DEVICE AND ASSOCIATED METHODS - Voltage converters with integrated low power leaker device and associated methods are disclosed herein. In one embodiment, a voltage converter includes a switch configured to convert a first electrical signal into a second electrical signal different than the first electrical signal. The voltage converter also includes a controller operatively coupled to the switch and a leaker device electrically coupled to the controller. The controller is configured to control the on and off gates of the switch, and the leaker device is configured to deliver power to the controller. The leaker device and the switch are formed on a first semiconductor substrate, and the controller is formed on second semiconductor substrate separate from the first semiconductor substrate.12-02-2010
20100321957STANDBY POWER METHOD AND APPARATUS FOR POWER MODULE APPLICATIONS - The present invention discloses a standby power saving method for power module applications, comprising the steps of: generating a mode signal according to voltage comparison of a feedback signal and a threshold voltage, wherein the mode signal has a normal mode state and a standby mode state; generating a pulse signal according to the mode signal, wherein the pulse signal has a normal PWM mode responsive to the normal mode state of the mode signal, and a V12-23-2010
20090016082Systems and Methods for Frequency Control of a Voltage Converter - Various embodiments of the present invention provide voltage converters and methods for using such. As one example, a voltage converter is disclosed that includes a transformer, an operational detector, and a controllable oscillator. The transformer includes a first winding and a second winding, and the operational detector provides an electrical output corresponding to an operational characteristic of the transformer. The controllable oscillator provides a clock output with a frequency corresponding to the electrical output. This clock output at least in part controls application of a voltage input to the first winding.01-15-2009
20100135046PREDICTIVE CONTROL SYSTEM - The first sampling measurement value compares whether to exceed a prescribed threshold and judges the control part at the sampling time. The control part compares whether the first sampling measurement value exceeds a prescribed threshold. When the actual measurement value doesn't exceed a prescribed threshold, the control part predict the first sampling value at the next sampling time. [1] When the first sampling the predicting value doesn't exceed the threshold value, the status of the switch is maintained, [2] When the first sampling the predicting value exceeds the threshold value, the time when the movement of the switch should be changed is calculated and the status of the switch is changed at time concerned.06-03-2010
20110075448SWITCHING POWER CONVERTER CONTROLLER WITH DIRECT CURRENT TRANSFORMER SENSING - A power control system includes a current transformer to step down a switch current of a switching power converter. In at least one embodiment, the stepped down current is received by a switching power converter controller. Since the current is received by the controller, the current is not converted into a voltage prior to receipt by the controller in order for the controller to monitor an inductor current of the switching power converter. In at least one embodiment, the controller compares the stepped down switch current with a reference current. In at least one embodiment, the controller includes a voltage converter to convert the switch current into a voltage within the controller. The controller compares the voltage representing the switch current with a reference voltage. The controller can use the current or voltage comparisons to control power factor correction and output voltage regulation of a switching power converter.03-31-2011
20100259953METHOD AND APPARATUS FOR LIMITING MAXIMUM OUTPUT POWER OF A POWER CONVERTER - An example power converter includes a power switch, a controller, and a current offset circuit. The controller is coupled to switch the power switch between an ON state and an OFF state to regulate an output of the power converter. The controller is adapted to terminate the ON state of the power switch in response to a switch current flowing through the power switch reaching a switch current threshold. The current offset circuit is coupled to generate an offset current in response to an input voltage of the power converter and an input current of the power converter is adjusted in response to the offset current.10-14-2010
20110211369LOW OUTPUT VOLTAGE CONVERTER UTILIZING DISTRIBUTED SECONDARY CIRCUITS - Embodiments of the present invention relate to a low-output voltage converter, delivering voltage power less than 1 VDC, utilizing distributed secondary circuits. In one embodiment of the present invention, there is provided a voltage converter comprises a primary circuit for receiving an input voltage, comprising a plurality of primary windings arranged in series, a plurality of secondary circuits, each comprising a secondary winding for aligning with a primary winding to form a transformer, and each of the secondary circuits arranged in parallel, and an output for providing an output voltage down to, or less than 1 VDC.09-01-2011
20110075447SINGLE STAGE POWER CONVERSION UNIT WITH CIRCUIT TO SMOOTH AND HOLDUP DC OUTPUT VOLTAGE - The Power Conversion Unit includes a single stage rectifier circuit that generates a DC voltage which is stored on a first capacitor. A circuit arrangement connected to the first capacitor monitors the DC voltage at the capacitor and other predefined signals to generate signals for smoothing ripples associated with the DC voltage and maintains the DC voltage at a predefined level for a predefined time interval. The holdup and smoothing voltages are generated by developing and storing a high voltage on a second capacitor. A switching device connected to the second capacitor causes energy to flow from the second capacitor into the primary winding of a transformer whose secondary winding are switched to deposit the energy stored in said transformer onto the first capacitor. A circuit for charging the second capacitor is also provided.03-31-2011
20100165665Power supply control circuit and method for sensing voltage in the power supply control circuit - The present invention discloses a power supply control circuit, the power supply providing an output voltage to an output terminal from an input terminal through a transformer having a primary winding and a secondary winding, the power supply control circuit comprising: a power switch electrically connected with the primary winding; a switch control circuit controlling the power switch; and a sensing circuit supplying an output signal to the switch control circuit according to voltage signals obtained from two sides of the primary winding, wherein the sensing circuit includes a setting circuit for deciding the output voltage according to a reference signal. The present invention also relates to a voltage sensing method in the power supply control circuit.07-01-2010
20100195353SWITCHING POWER SUPPLY APPARATUS - A switching power supply apparatus includes a transformer or an inductor, a switching element connected to the transformer or the inductor and configured to perform switching of an input power supply, and a switching control circuit including a digital control circuit configured to sample voltage values and/or current values and control on and off of the switching element in accordance with the voltage values and/or current values. The number of points of sampling is set to n or more points, where n is an integer greater than 3, in an ON period of the switching element except at around a turn-on point or a turn-off point of the switching element. The presence or absence of magnetic saturation of the transformer or the inductor is detected on the basis of whether or not a slope of change in current value over time is larger than a predetermined value, and circuit operation is protected from the effect of magnetic saturation. Thus, the presence or absence of magnetic saturation can be rapidly and precisely detected without the influence of switching noise.08-05-2010
20110188268SIGNAL STATUS DIAGNOSING DEVICE FOR EXTERNAL CONTROL MEANS TO BE ACTIVATED WHEN FED WITH DRIVING ELECTRIC POWER BY ON/OFF SIGNAL TRANSMITTED THROUGH INSULAIING MEANS - This aims to provide a signal status diagnosing device for an external control means, which is enabled even by a simple constitution to prevent the rise of a production cost due to the increase in a parts count or the complexity of a circuit constitution, and which can perform a signal status diagnosis of an actuator (the external control means) such as an electromagnetic valve, a lamp, a relay or a small-sized DC motor precisely. The signal status diagnosing device comprises a switch circuit connected with an intermediate tap disposed on the primary side of a transformer, for sending a driving electric power to the external control means disposed on the secondary side, in response to an ON/OFF signal of the external control means, and a means connected with the switch circuit and driven by the external control means, for measuring the primary side electric current to flow in a manner to correspond to the electric current to flow to the transformer secondary side. The signal status diagnosing device diagnoses the signal status of the external control means in accordance with the measurement result of the current measuring means.08-04-2011
20090175054Method for Operating a Switched Mode Power Supply With Return of Primary-Side Stray Energy - The invention relates to a method for operating a switched mode power supply as an isolating transformer. According to said method, magnetic energy is stored in the core of a transformer during a storage stage via a primary coil that is connected to an intermediate circuit current and the stored magnetic energy is delivered to a load in a subsequent discharge phase, for the most part by means of a secondary coil, a small part of said magnetic energy being discharged on the primary side. The energy that is discharged on the primary side charges a capacitor in such a way that the capacitor current is always held above the secondary current multiplied by the transmittance ratio of the transformer.07-09-2009
20090116264Power supply circuit with voltage converting circuits and control method therefor - An exemplary power supply circuit (05-07-2009
20110317450AC-TO-DC POWER CONVERTING DEVICE - An AC-to-DC power converting device includes: a filter for filtering an external AC input voltage; a rectifier for rectifying the AC input voltage filtered by the filter to output a rectified voltage; a power factor corrector for receiving the rectified voltage from the rectifier to generate a boosted voltage; and a step-down converter for receiving the boosted voltage from the power factor corrector to output a DC output voltage. The power factor corrector includes first and second capacitors connected in series across an output side of the rectifier, a series connection of a first diode, a first inductor, a third capacitor, a second inductor and a second diode coupled to the output side of the rectifier, and first and second switches connected in series across the third capacitor. A common node between the first and second capacitors is coupled to a common node between the first and second switches.12-29-2011
20110157919VCC GENERATOR FOR SWITCHING REGULATOR - A voltage across a capacitor provides a supply voltage for circuits in an integrated circuit used to control a switching voltage regulator. The capacitor is charged during an OFF portion of a pulse width modulated (PWM) control signal that controls a first transistor in the switching voltage regulator. The voltage across the capacitor is controlled to be between a high threshold and a low threshold. The voltage is controlled by comparing the voltage across the capacitor to a low threshold and charging the capacitor during the OFF portion of the PWM signal if the voltage across the capacitor is below the low threshold. The voltage across the capacitor is compared to a high threshold and the capacitor is not charged if the voltage across the capacitor is above the high threshold.06-30-2011
20100259952SWITCHING MODE POWER SUPPLY CONTROLLER WITH HIGH VOLTAGE STARTUP CIRCUITS - A controller for a switching mode power supply includes two semiconductor chips. The first semiconductor chip has a high-voltage startup transistor coupled to a high-voltage supply input terminal and configured to provide a charging current in a startup phase or protection mode of a switching mode power supply (SMPS) and to provide substantially no current in a normal operation phase of the SMPS. The second semiconductor chip has a control circuit for controlling the switching mode power supply. The second semiconductor chip also has first and second on-chip high-voltage resistors coupled to the high-voltage supply input terminal and the high-voltage startup transistor in the first semiconductor chip. The first and the second on-chip high-voltage resistors are configured to provide a voltage and a current related to a voltage at the high-voltage supply input terminal.10-14-2010
20100091523SWITCHING POWER SUPPLY APPARATUS - A digital signal processing circuit which performs average current control is disposed on a secondary side of a transformer of an isolated DC-DC converter, and a switching control signal output from the digital signal processing circuit is transmitted to a switching element included in a power factor correction converter through an isolated drive circuit. The digital signal processing circuit obtains an average value of currents supplied to an inductor in accordance with a voltage output from a bias winding of the inductor or an output from a secondary side of a current transformer which detects a drain current of the switching element. Furthermore, the average value of the currents corresponds to a waveform (full-wave rectification sine wave) of an input voltage Vi.04-15-2010
20100202161POWER CONVERTER WITH AUTOMATIC MODE SWITCHING - A power converter is provided that has an alternating-current (AC) to direct-current (DC) switched-mode power converter circuit that converts alternating-current power into direct-current power for powering an attached electronic device. Power can be conserved by automatically placing the power converter circuit in a low-power standby mode of operation whenever the electronic device is detached from the power converter. A monitoring circuit can be powered by a capacitor or other energy storage element while the power converter is operating in the standby mode. If the monitoring circuit detects an output voltage change that is indicative of attachment of the electronic device or if the storage element needs to be replenished, the monitoring circuit can place the power converter circuit in an active mode of operation.08-12-2010
20090251928Switching power supply circuit - A switching power supply circuit includes a direct current (DC) power supply input terminal, a first transformer including a first primary winding, a second transformer, and a pulse generating circuit, and a startup circuit. The pulse generating circuit includes first and second first switching units connected in series and two voltage division resistors connected in series between the DC power supply input terminal and ground, and two capacitors connected in parallel with one of the two voltage division resistors. The second transformer includes a second primary winding connected between control terminal and second conducting terminal of the first switching unit, a second secondary winding; and an assistant winding connected between the control terminal of the second switching unit and ground. The second conducting terminal of the first switching unit is grounded via the second secondary winding, the first primary winding and a capacitor in series.10-08-2009
20110122657SWITCH WITH COMMON-MODE CHOKE - A common-mode choke level-shifter drives a power switch with sub-nanosecond timing integrity without requiring a high-side gate-drive power supply. The same level-shifter may also be used to drive a low-side switch to avoid ground bounce effects.05-26-2011
20080298088DC TO DC CONVERTER WITH LOAD OPEN DETECTION AND RELATED METHOD THEREOF - Disclosed is a DC to DC converter, which comprises: a transforming circuit, for transforming an input voltage to an output voltage; a comparator, for comparing a reference voltage and a feedback voltage proportional to the output voltage to generate a comparing signal; a control circuit, coupled to the transforming circuit and the comparator, for controlling the transforming circuit according to the comparing signal; and a time-counting device, coupled to the control circuit, for counting the time of a specific voltage level of the comparing signal; wherein the time-counting device informs the control circuit that a load open situation occurs if the specific voltage level of the comparing signal lasts a predetermined time, then the control circuit turns off the transforming circuit.12-04-2008
20100232182DUAL-SWITCHES FLYBACK POWER CONVERTER WITH SELF-EXCITED SUPPLY TO POWER THE HIGH-SIDE DRIVER - An exemplary embodiment of a flyback power converter includes a transformer for power transfer, a high-side transistor, a low-side transistor, two diodes, a control circuit, and a high-side drive circuit. The high-side transistor and the low-side transistor are coupled to switch the transformer. The two diodes are coupled to said transformer to circulate energy of leakage inductance of the transformer to an input power rail of the power converter. The control circuit generates a switching signal coupled to control the high-side transistor and the low-side transistor. The high-side drive circuit is coupled to receive the switching signal for driving the high-side transistor. The transformer has an auxiliary winding generating a floating power to provide power supply for said high-side drive circuit.09-16-2010
20090303753Multi-Element Resonant Converters - A resonant switched power converter having switching frequency controlled in response to an output voltage thereof achieves over-current protection such as at start-up or under short circuit conditions using a resonant tank circuit which provides a notch filter in addition to a band pass filter. A additional band pass filter provided in the resonant tank circuit achieves increased power transfer to a load and reduced circulating resonant currents and conduction losses. The inductances of the preferred LCLCL tank circuit or other tank circuit with two pass band filters and a notch filter may be integrated into a single electrical component.12-10-2009
20130188398DEVICES AND METHODS FOR CONVERTING ALTERNATING CURRENT (AC) POWER TO DIRECT CURRENT (DC) POWER - Methods, circuit designs, systems, and devices for the conversion of high voltage alternating current (AC) to low voltage, high current direct current (DC) are described. An exemplary apparatus includes a rectifier for receiving a high voltage AC line power input and for outputting a full wave, high voltage DC, a gating component coupled to the rectifier for receiving the high voltage DC output by the rectifier, wherein the gating component is configured to gate the high voltage DC by turning on at a zero crossing level and turning off when the high voltage DC exceeds a preset voltage threshold and wherein the output of the gating component is an intermediate voltage DC capped by the preset voltage threshold, and a DC-DC converter coupled to the gating component for receiving the intermediate voltage DC output by the gating component, wherein the DC-DC converter is configured to step down and smooth out the intermediate voltage DC to a desired high current, low voltage DC output.07-25-2013
20130194830POWER SUPPLY DEVICE - A power supply device includes a transformer; a series circuit of two bidirectional switching elements connected between terminals of the commercial power supply and having a rectification function and a switching function; an LC resonant circuit connected between a primary coil of the transformer and both ends of one of the bidirectional switching elements; a rectifying element connected to a secondary coil of the transformer; and a control circuit for inputting a gate driving signal to the bidirectional switching elements. The power supply device performs synchronous rectification from the bidirectional switching elements.08-01-2013

Patent applications in class Single-ended, separately-driven type

Patent applications in all subclasses Single-ended, separately-driven type