Class / Patent application number | Description | Number of patent applications / Date published |
363210060 | Having synchronous rectifier | 68 |
20080247196 | Switched Mode Power Supply With Synchronous Rectifier - In a controller (CC | 10-09-2008 |
20080253149 | COMPOSITE TRANSFORMER AND INSULATED SWITCHING POWER SOURCE DEVICE - An E-shaped transformer core has a middle leg and one pair of outer legs and on opposite sides with respect to the middle leg. A first pair of coils including at least two coils are wound around the middle leg so that a power transmission transformer unit is formed. The outer leg is divided into two outer leg portions and with a space therebetween allowing coil wiring therebetween, and a second pair of coils including two coils are respectively wound around the respective two outer leg portions and so as to have mutually opposite winding directions, so that a signal transmission transformer unit is formed. | 10-16-2008 |
20080266909 | CHIPSET FOR ISOLATED POWER SUPPLY WITH NEW PROGRAMMABLE SYNCHRONIZATION ARCHITECTURE - A chipset for an isolated power supply having an innovative oscillator includes a primary controller and a secondary controller. The primary controller can have the control and drive circuitry for the chipset. The secondary controller can provide rectification signals that can be synchronized with a power MOSFET. | 10-30-2008 |
20080273354 | Power Supply - There are provided an inductive load current control circuit for detecting and controlling a current flowing to an inductive load with high accuracy, and a power supply. | 11-06-2008 |
20080278972 | Power conversion circuit, driving method and drive unit therefor - A power conversion circuit capable of varying an output voltage within a range from a negative voltage lower than a ground voltage to a positive voltage higher than a supply voltage, and a driving method and a drive unit are provided. A power conversion circuit includes a transformer with a 1:1 ratio between the primary winding and secondary winding, a voltage outputting capacitor, and four switches. The power conversion circuit can be operated as a DC-DC converter of a step-up type, a step-up-and-down type, a step-down type, an inverted-output step-up-and-down type, or an inverted-output step-up type by selecting two switches used for control from among the four switches and alternately turning the two switches on. By switching the operating modes of the power conversion circuit, the output voltage can be varied within a range from a negative voltage to a positive voltage higher than a supply voltage. | 11-13-2008 |
20080285312 | Phase Compensation Driving Scheme for Synchronous Rectifiers - Phase compensation of a voltage appearing on physical terminals of a synchronous rectifier switching element such as a MOSFET is used to substantially eliminate effects of package inductance of the synchronous rectifier and thus approximate the actual voltage across the circuit element providing synchronous rectification in, for example, a switching power converter. By doing so and using the phase compensated signal to control the synchronous rectifier, switching time may be more suitably controlled to improve efficiency of the synchronous rectifier by substantially eliminating body diode conduction and body diode reverse recovery effects. | 11-20-2008 |
20080298093 | MULTIPHASE RESONANT CONVERTER FOR DC-DC APPLICATIONS - The various embodiments and example provided herein are generally directed to novel multiphase resonant converters. In an embodiment, a multiphase resonant converter comprises N unit resonant converters having inputs and outputs connected in parallel, respectively. Each unit converter comprises an inverter, a LLC series resonant tank, and a rectifier. In a preferred embodiment, the inverters of the N unit converters are driven by N drive signals phase-shifted 2π/N degrees apart. During operation, the current of the multiphase converter is shared among the unit converters, resulting in a smaller current in each unit converter. The smaller current in each unit converter reduces conduction losses, thereby increasing the efficiency of the multiphase converter. In addition, the smaller current in each unit converter reduces the amount of stress placed on individual components of the converter allowing for the use of lower tolerance components. Further, the multiphase converter has automatic current sharing ability. | 12-04-2008 |
20080304291 | Switched Mode Power Converter and Method of Operation Thereof - A switched mode power converter is provided which includes a transformer ( | 12-11-2008 |
20090003019 | SYNCHRONOUS RECTIFICATION CIRCUIT FOR POWER CONVERTERS - A synchronous rectification circuit for power converters operable under fixed and/or variable frequencies where no current sense circuit or phase-lock circuit are needed is provided. It has a power switch coupled to a transformer for the rectification. A signal-generation circuit is used for generating a control signal in response to a magnetized voltage of the transformer, a demagnetized voltage of the transformer, and a magnetization period of the transformer. The control signal is coupled to turn on the power switch. The enable period of the control signal is correlated to a demagnetization period of the transformer. | 01-01-2009 |
20090040792 | SYNCHRONOUS RECTIFYING CIRCUIT FOR RESONANT POWER CONVERTERS - A synchronous rectifying circuit is provided for resonant power converter. An integrated synchronous rectifier comprises a rectifying terminal, a ground terminal a first input terminal and a second input terminal. The rectifying terminal is coupled to the secondary side of a power transformer. The ground terminal is coupled to the output of the power converter. A power transistor is connected between the rectifying terminal and the ground terminal. The first input terminal and the second input terminal are coupled to receive a pulse signal for turning on/off the power transistor. A pulse-signal generation circuit includes an input circuit coupled to receive the switching signal for switching the power transformer of the power converter. | 02-12-2009 |
20090080223 | FORWARD CONVERTER WITH SELF-DRIVEN SYNCHRONOUS RECTIFIERS - The present invention relates to a forward converter with self-driven synchronous rectifiers, which utilizes a secondary driving winding and a secondary driving circuit to drive the synchronous rectifiers in the secondary power loop. The secondary driving circuit, which is composed of a level shifter and a signal distributor, can shift the voltage waveform across the secondary driving winding by a predetermined level and distribute proper driving signals to the synchronous rectifiers to reduce the rectifier conduction loss. Specially, the channel of the freewheeling synchronous rectifier still can be turned on during the dead interval to further reduce the body diode conduction loss. | 03-26-2009 |
20090086512 | Driving a primary-side switch and a secondary-side rectifier element in a switching converter - An apparatus, comprising a transformer comprising a first winding and a second winding; a first switch coupled to the first winding and configured to alternate between an off state and an on state in response to a pulsed first signal; a rectifier coupled to the second winding and configured to alternate between an off state and an on state in response to a pulsed second signal; and a drive circuit configured to generate the first and second signals such that the first switch and the rectifier are switched to the on state in a temporally offset relation with each other. | 04-02-2009 |
20090091951 | CONTROL CIRCUIT FOR SYNCHRONOUS RECTIFYING AND SOFT SWITCHING OF POWER CONVERTERS - A control circuit for soft switching and synchronous rectifying is provided for power converter. A switching-signal circuit is used for generating drive signals and a pulse signal in response to a leading edge and a trailing edge of a switching signal. The switching signal is developed for regulating the power converter. Drive signals are coupled to switch the power transformer. A propagation delay is developed between drive signals to achieve soft switching of the power converter. An isolation device is coupled to transfer the pulse signal from a primary side of a power transformer to a secondary side of the power transformer. A controller of the integrated synchronous rectifier is coupled to the secondary side of the power transformer for the rectifying operation. The controller is operated to receive the pulse signal for switching on/off the power transistor. The pulse signal is to set or reset a latch circuit of the controller for controlling the power transistor. | 04-09-2009 |
20090161390 | Synchronous Rectification Control Circuit Assembly - A synchronous rectification control circuit assembly includes a first transformer, a reference voltage generator, a first PWM control signal generating circuit, a second PWM control signal generating circuit, a first synchronous rectification circuit, and a second synchronous rectification circuit. When the output voltage rises, the conduction time of the first synchronous rectification circuit and the second synchronous rectification circuit are relatively regulated to lower the output voltage, maintaining stability of the output voltage. | 06-25-2009 |
20090168464 | Synchronous rectifier control device and a forward synchronous rectifier circuit - A synchronous rectifier control device comprises a status detecting unit, an analog circuit, a first counter, a second counter and a signal process unit. The status detecting unit receives at least one reference signal and a detecting signal to generate a first synchronous control signal. The analog circuit generates a delay signal in accordance with the first synchronous control signal. The first counter receives a clock signal and generates a first counter signal in accordance with the first synchronous control signal, the clock signal, and the delay signal. The second counter receives the clock signal and generates a second counter signal in accordance with the first synchronous control signal, the clock signal, and the first counter signal. The signal process unit generates a second synchronous control signal in accordance with the first synchronous control signal and the second signal. | 07-02-2009 |
20090175056 | Synchronous Rectifier - This invention relates to a synchronous rectifier for LLC resonant converter. This method allows simple drive method for the synchronous rectifier MOSFETS by using the transformer secondary winding voltage and one-shot vibrator. The synchronous rectifier MOSFETs are turned on by being triggered to the transformer secondary side winding voltage and turned off after predetermined time set by one shot vibrator. The predetermined time is set by the resonant period of the resonant network. | 07-09-2009 |
20090196075 | FLY-FORWARD CONVERTER POWER SUPPLY - A fly-forward converter topology for a switched-mode power supply (SMPS) that may incorporate the advantages of both a forward converter and a flyback converter into a two-stage half-wave converter is provided. The fly-forward converter may be considered as a half-wave forward converter that has been modified with the addition of another secondary winding and a second rectifier, operating as a forward converter during the on period of the primary-side switch(es) and functioning as a flyback converter during the off period. Magnetizing energy stored in the core of the converter's transformer is not lost or recirculated in the primary, but may be transferred from the primary to the secondary. By transferring the transformer magnetizing energy to the secondary during the off period, the transformer core of the fly-forward converter may be reset without additional core resetting circuitry. | 08-06-2009 |
20090244932 | Synchronous Rectifying Apparatus and Forward Synchronous Converter - A synchronous rectifying apparatus suitable for use in a forward synchronous converter having a transforming unit with a primary and secondary side, and a first and second rectifying switches coupled to the secondary side is provided. The synchronous rectifying apparatus has a condition detecting unit and a synchronous rectifying controller. The condition detecting unit; coupled to the secondary side of the transforming unit, for detecting if the operation condition of the forward synchronous converter is at boundary between discontinuous current mode and continuous current mode or under discontinuous current mode based on the rising slope of the secondary side voltage of the transforming unit. If so, the condition detecting unit outputs a reset signal. The synchronous rectifying controller, coupled to the secondary side of the transforming unit and the condition detecting unit, to turn off the second rectifying switch for a predetermined time period in response to the reset signal. | 10-01-2009 |
20090244933 | HALF-BRIDGE LLC RESONANT CONVERTER WITH SELF-DRIVEN SYNCHRONOUS RECTIFIERS - The present invention discloses a half-bridge LLC resonant converter with self-driven synchronous rectifiers, which utilizes a primary IC controller and a gate driver to drive the secondary synchronous rectifiers. In correspondence with the gate drive output voltages of the primary IC controller to the primary switch transistors, the gate driver for the secondary synchronous rectifiers comprises a differential transformer if the primary IC controller outputs two ground-referenced gate drive voltages, which cannot directly drive the primary switch transistors but can be imposed on the differential transformer; or comprises a DC shifter, a DC restorer and a differential transformer if the primary IC controller outputs two gate-source voltages, which can directly drive the primary switch transistors but cannot be imposed on the differential transformer. The drive voltages of the primary switch transistors are unipolar; however the drive voltage of the secondary synchronous rectifiers can be bipolar or unipolar. Under the valid operation mode, this converter can decrease the rectifier conduction losses to increase the power converter efficiency. | 10-01-2009 |
20090244934 | SYNCHRONOUS RECTIFICATION CIRCUIT HAVING BURST MODE CONTROLLER AND CONTROLLING METHOD THEREOF - The configuration of a synchronous rectification circuit and a controlling method thereof are provided. The proposed circuit includes a converter including a first switch and a first synchronous rectifier, and a burst mode controller including a logic process module performing one of functions of delaying one of a non-integer and at least one operating periods to generate a synchronous rectification driving signal of the first synchronous rectifier counting from a beginning of a first pulse of a driving signal of the first switch during a working time of a burst period, and turning off the synchronous rectification driving signal of the first synchronous rectifier by one of the non-integer operating period and the at least one operating period ahead of an ending of a last operating period of the driving signal of the first switch during the working time of the burst period. | 10-01-2009 |
20090257250 | SYNCHRONOUS RECTIFIER DC/DC CONVERTERS USING A CONTROLLED-COUPLING SENSE WINDING - A synchronous rectifier DC/DC converter is provided. The synchronous rectifier DC/DC converter includes a power transformer, a first diode, a first MOSFET, and a first controller. The power transformer includes a core, a primary winding, a secondary winding, and a sense winding. The primary winding is wrapped around the core and receives an input voltage of the synchronous rectifier DC/DC converter. The secondary winding is wrapped around the core and provides the energy of an output current of the synchronous rectifier DC/DC converter. The sense winding is wrapped around the core and provides a sense signal. The first diode is coupled to the secondary winding for rectifying the output current. The first MOSFET is coupled in parallel with the first diode. The first controller is coupled to the sense winding and the first MOSFET for turning on and turning off the first MOSFET according to the sense signal. | 10-15-2009 |
20090262560 | Current Controlled Synchronous Rectifying Drive Circuit - A current controlled synchronous rectifying drive circuit including a current transducer ST having a primary winding connected in series with a synchronous rectifier SR and having a secondary winding to detect a current signal of a synchronous rectifier SR, a signal shaping and reset circuit connected to the secondary winding of the current transducer ST to convert the synchronous rectifier SR's current signal into a voltage signal and shapes it into a pulse signal, a push-pull power amplifying circuit having an input end connected to the signal shaping and reset circuit and an output end connected to a gate of the synchronous rectifier SR to amplify a drive signal generated by the signal shaping and reset circuit to drive the synchronous rectifier SR, and a drive self-bias drive circuit having an input end connected to the secondary winding of the current transducer ST and an output end connected to the push-pull power amplifying circuit to store energy from the current transducer ST to generate a voltage source. | 10-22-2009 |
20090273951 | SMART DRIVING METHOD FOR SYNCHRONOUS RECTIFIER AND ITS APPARATUS THEREOF - The present invention discloses a smart driving method for a secondary synchronous rectifier of an isolated converter and its apparatus thereof. The apparatus comprises: a main circuit having a secondary synchronous rectifier Q | 11-05-2009 |
20090279326 | SWITCHING POWER SOURCE APPARATUS - Disclosed a switching power source apparatus including: a transformer including a primary winding and a secondary winding; a switching element to intermittently apply a voltage to the primary winding by an on-off operation; and a synchronous rectifying element to rectify a current in the secondary winding, wherein the switching power source apparatus is a flyback system switching power source apparatus to receive input of electric power from a primary winding side to perform voltage output to a secondary wiring side, and the switching power source apparatus further comprises a load detection circuit to compare an output voltage to be output onto the secondary winding side with a voltage at a node between the synchronous rectifying element and the transformer by adding predetermined weighting to the voltages to be compared so as to generate a signal indicating a magnitude of an output load. | 11-12-2009 |
20090284992 | METHOD AND SYSTEMS FOR CONDUCTION MODE CONTROL - Methods for selecting between the two modes (states) of operation, continuous conduction and discontinuous conduction, are disclosed. Systems that are capable of selecting the operating mode and operating in the continuous conduction mode or the discontinuous conduction mode are also disclosed. | 11-19-2009 |
20090303755 | POWER CONVERTER APPARATUS - A power converter apparatus for receiving an input voltage and produces an output voltage by converting includes a switching-type voltage converting circuit circuit and a voltage level tuning circuit. The switching-type voltage converting circuit circuit includes an inductor, a switch and a synchronous rectifier, wherein the switch is for disabling/enabling the energy-storing operation conducted by the inductor. The synchronous rectifier produces the output voltage by using the stored electrical energy during the above-mentioned energy-storing operation. Besides, the voltage level tuning circuit is across coupled onto the switch for reducing the voltage difference between the two terminals of the switch. | 12-10-2009 |
20090316441 | Synchronous Rectifier Control Circuit and Method - In accordance with an embodiment of the present invention, a method of operating a switched power supply is disclosed. The method comprises determining a current load on a secondary side of a transformer by measuring a ratio between a secondary side current conduction time and a primary switching period of the power supply and comparing the current load with a predetermined threshold. A synchronous rectification (SR) MOSFET coupled to the secondary side of the transformer is disabled if the current load is less than the preset threshold. | 12-24-2009 |
20090316442 | METHOD FOR OPERATING A RESONANT POWER CONVERTER - According to an exemplary embodiment a method of operating a resonant power supply comprises controlling the resonant power supply in a discontinuous way. According to an exemplary embodiment a resonant power supply comprises a first switching element, and at least one energy storing element, wherein the resonant power supply is adapted to be controlled in a discontinuous way. | 12-24-2009 |
20090316443 | AC/DC INTERMEDIATE-CIRCUIT CONVERTER HAVING A VERY WIDE AC INPUT VOLTAGE RANGE - An AC/DC intermediate-circuit converter has a very wide AC input voltage range with a ZVS three-level DC/DC resonant converter with an LLC series-resonant circuit. Two intermediate-circuit capacitors are connected in series between DC intermediate-circuit connections with their common connection point forming a DC intermediate-circuit centre connection ( | 12-24-2009 |
20090323375 | Discontinuous Conduction Mode Control Circuit and Method for Synchronous Converter - Circuit and method for controlling a synchronous power converter in discontinuous conduction mode with increased efficiency is disclosed. Circuitry is provided outputting gating signals to a high side driver and a synchronous rectifier responsive to a pulse width modulated input signal, an inhibit circuit for inhibiting the gating signal to the synchronous rectifier upon detection of a zero crossing condition; a comparator receiving a measured circuit value from the synchronous converter and a reference value and outputting a zero crossing condition; and a duty cycle observer circuit for determining the average duty cycle of the pulse width modulated input signal and for varying the reference value. A method is disclosed determining if the average duty cycle in the pulse width modulated input signal is increasing in response to varying a reference value, and inhibiting a synchronous rectifier control signal when the comparator indicates a zero crossing condition. | 12-31-2009 |
20100002473 | Multiple-Output Dual-Polarity DC/DC Converters and Voltage Regulators - A multi-output dual polarity inductive boost converter includes an inductor, a first output node, a second output node, and a switching network, the switching network configured to provide the following modes of circuit operation: a first mode where the positive electrode of the inductor is connected to an input voltage and the negative electrode of the inductor is connected to ground; 2) a second mode the negative electrode of the inductor is connected to ground and the positive electrode of the inductor is connected in sequence to one or more of the fourth and fifth output nodes; and 3) a third mode where the positive electrode of the inductor is connected to the input voltage and the negative electrode of the inductor is connected in sequence to one or more of the first, second and third output nodes. | 01-07-2010 |
20100014324 | OFFLINE SYNCHRONOUS RECTIFYING CIRCUIT WITH SENSE TRANSISTOR FOR RESONANT SWITCHING POWER CONVERTER - A synchronous rectifying circuit of a resonant switching power converter is provided to improve the efficiency. The synchronous rectifying circuit includes a power transistor and a diode connected to a transformer and an output ground of the power converter for rectifying. A sense transistor is coupled to the power transistor for generating a mirror current correlated to a current of the power transistor. A controller generates a driving signal to control the power transistor in response to a switching-current signal. A current-sense device is coupled to the sense transistor for generating the switching-current signal in response to the mirror current. The controller enables the driving signal to turn on the power transistor once the diode is forwardly biased. The controller generates a reset signal to disable the driving signal and turn off the power transistor once the switching-current signal is lower than a threshold. | 01-21-2010 |
20100067262 | Switching power source device, switching power source control circuit, and switching power source device control method - A switching power source device for supplying power to a load includes a series resonant circuit, a plurality of main switch elements or main switch element groups for switching a current. path of the series resonant circuit, a transformer for inducing a secondary current from the series resonant circuit, a plurality of synchronous rectification switch elements for rectifying the secondary current, a maximum on width control circuit for ordering a start and a completion of a maximum on width to the synchronous rectification switch element in synchronization with a timing of turning on the main switch elements Or the main switch element groups, and a synchronous control circuit. The circuit controls an on period of the synchronous rectification switch element so as to turn on the synchronous rectification switch element in synchronization with a particular timing, and turn off in synchronization with another timing. | 03-18-2010 |
20100149839 | Synchronous Rectifier - The disclosed embodiments relate to apparatus and method for reducing power losses in a power supply. There is provided an apparatus comprising means ( | 06-17-2010 |
20100188872 | ISOLATED SWITCHING POWER SUPPLY DEVICE - An isolated switching power supply device includes a main transformer having a primary coil on a primary circuit side and a secondary coil on a secondary circuit side. On the primary circuit side are disposed an input smoothing capacitor, a switching control circuit, a high-side driver, a low-side power switch, a high-side power switch, capacitors, and edge signal-generating circuits. A symmetrical control half bridge converter is thus provided. The secondary circuit side has a voltage clamping circuit including a clamp capacitor, a clamp switch and a diode. | 07-29-2010 |
20100226150 | METHOD AND DEVICE FOR REGULATING A RESONANT INVERTER EQUIPPED WITH SUCH A DEVICE - Embodiments of the present invention relate to a method and device for regulating a series resonant inverter with controlled rectification. It also relates to a resonant inverter equipped with such a device. The synchronous series resonant inverter includes a primary winding having across its terminals a periodic voltage V(t) of period T, this primary winding being coupled to at least one secondary winding providing the output voltage Vs. The establishment of the current I | 09-09-2010 |
20100309691 | DC/DC CONVERTER WITH FULLWAVE REGULATION - A secondary circuit for a DC/DC converter, the secondary circuit having a main outlet and an auxiliary outlet, the secondary circuit comprising a main automatically controlled synchronous rectifier circuit receiving a voltage from the secondary winding of a transformer having an intermediate tap and delivering firstly a fullwave first rectified voltage for the main outlet and secondly a halfwave second rectified voltage, and an auxiliary synchronous rectifier circuit controlled by a synchronous post regulation control circuit receiving the halfwave second rectified voltage V | 12-09-2010 |
20110013424 | FORWARD CONVERTER WITH SECONDARY SIDE POST-REGULATION AND ZERO VOLTAGE SWITCHING - The present invention discloses a forward converter with secondary side post-regulation and zero voltage switching, where the primary side power loop may adopt a single or a dual transistor structure, driven by a primary side driving circuit with a constant duty ratio so that the voltage waveform across the secondary side power winding has a constant pulse width; the secondary side power loop uses a controllable switch, a magnetic amplifier (MA) or an N channel metal oxide semiconductor field transistor (NMOS), to blank the leading edge of the voltage waveform across the secondary side power winding, regulate the output voltage, and achieve zero voltage switching of primary side switch transistors. | 01-20-2011 |
20110038182 | POWER CONVERTER HAVING SYNCHRONOUS RECTIFIER AND CONTROL METHOD OF SYNCHRONOUS RECTIFIER - Disclosed is a power converter including a switching circuit; a transformer having a primary winding connected to the switching circuit and a secondary winding; a main control circuit connected to the switching circuit for outputting a main control signal to manipulate the switching circuit; at least one synchronous rectifier connected to the secondary winding; at least one current transformer connected to the synchronous rectifier for outputting a detecting signal according to a current flowing through the synchronous rectifier; and at least one synchronous rectification control circuit connected to a control terminal of the synchronous rectifier, the current transformer, and a control terminal of the switching circuit for receiving the detecting signal and the main control signal for manipulating the synchronous rectifier. In case that the main control circuit manipulates the switching circuit to turn on, the synchronous rectification control circuit manipulates the synchronous rectifier to turn on, and thereby allowing the synchronous rectification control circuit to manipulate the synchronous rectifier to turn off according to the detecting signal. | 02-17-2011 |
20110044075 | POWER CONVERTER CAPABLE OF LOWERING POWER WASTAGE ON STANDBY - A power converter includes at least one electric control switch, an electric current detecting and converting unit, a power controller, and a voltage detecting and controlling unit at the primary side; and a synchronous rectifying circuit, two MOSFETs, and an oscillating loop. During the actual operation, electric current detecting and converting unit outputs an AC voltage signal to the power controller and outputs a DC voltage signal to the voltage detecting and controlling unit, and then voltage detecting and controlling unit compares with a reference voltage to turn off the synchronous rectifying circuit at the no-load mode and to rectify via a body diodes of the MOSFETs. Accordingly, the power converter can reduce the power wastage at the no-load mode to be energy-saving. | 02-24-2011 |
20110063877 | Synchronous rectifying circuit with primary-side swithching current detection for offline power converters - A synchronous rectifying circuit is provided for offline power converter. A pulse signal generator is utilized to generate a pulse signal in response to a switching current of the power transformer. An isolation device is coupled to the pulse signal generator for transferring the pulse signal through an isolation barrier of the power transformer. A synchronous rectifier includes a power switch and a control circuit. The power switch is coupled between the secondary side of the power transformer and the output of the power converter for the rectifying. The control circuit is operated to receive the pulse signal for turning on/off the power switch. The pulse signal is generated to turn on the power switch once the switching current is higher than a threshold. | 03-17-2011 |
20110188269 | SWITCHING POWER-SUPPLY APPARATUS - In a switching power-supply apparatus, a primary-side power converter circuit includes a half bridge system and a synchronous rectifier circuit is provided as a rectifier circuit of a secondary-side power converter circuit. An on time ratio of the on time of a first switching element to the on time of a second switching element is controlled so as to provide an operation mode in which energy is regenerated from the secondary side to the primary side when the load is light. | 08-04-2011 |
20110205763 | Power Converter with an Adaptive Controller and Method of Operating the Same - A controller for a power converter, and method of operating the same. The controller improves power converter operating efficiency by regulating an internal power converter operating characteristic depending on a value of a power converter parameter measured after a manufacturing step, or an environmental parameter, preferably employing a table with entries dependent on the parameter value. The internal operating characteristic may be an internal bus voltage, a voltage level of a drive signal for a power switch, a number of paralleled power switches selectively enabled to conduct, or a basic switching frequency of the power converter. The controller may regulate an internal operating characteristic of the power converter using a functional relationship dependent on the parameter value. The environmental parameter may be received as a signal from an external source. The parameter measured after a manufacturing step may be a parameter measured from representative power converter(s). | 08-25-2011 |
20110317453 | CONTROL CIRCUIT, CONTROL METHOD, AND POWER SUPPLY DEVICE - A control circuit, a control method, and a power supply device are provided. The control circuit includes an obtaining module, adapted to obtain a voltage signal from a reverse surge current when the reverse surge current appears on a primary side of a switch power circuit of a synchronous rectification circuit; a maintaining module, adapted to continuously output a first control signal in a preset first time period when the voltage signal is greater than a preset first voltage threshold; and a control module, adapted to control and switch off switch tubes of the secondary side of the switch power circuit of the synchronous rectification circuit according to the first control signal. Thus, a reverse current surge of the switch power circuit of the synchronous rectification circuit can be effectively suppressed, and the safety of a switch power supply of the synchronous rectification circuit can be effectively protected. | 12-29-2011 |
20120140526 | SYNCHRONOUS RECTIFIER BI-DIRECTIONAL CONVERTER - A system and method for bi-directional voltage conversion are disclosed. A charge current is received at a first voltage on a first force commutated synchronous rectifier, and the charge current is controlled by the first force commutated synchronous rectifier. An inductor is charged by the charge current, and a discharge current from the inductor is controlled by the second force commutated synchronous rectifier. | 06-07-2012 |
20130094251 | SELF-DRIVEN SYNCHRONOUS RECTIFIER DRIVE DIRCUIT, METHOD OF OPERATION THEREOF AND POWER CONVERTER INCORPORATING THE SAME - A drive circuit for a synchronous rectifier, a method of driving a synchronous rectifier and a power converter incorporating the drive circuit or the method. In one embodiment, the drive circuit includes: (1) a first drive circuit stage configured to derive a timing for at least one drive signal from a secondary winding of a transformer coupled to the synchronous rectifier and (2) a second drive circuit stage, coupled to the first drive circuit stage and configured to employ a substantially stable voltage source to provide power for the at least one drive signal and apply the at least one drive signal to at least one control terminal of at least one synchronous rectifier switch in the synchronous rectifier. | 04-18-2013 |
20130107582 | DC TO DC CONVERTOR | 05-02-2013 |
20130279207 | POWER SUPPLY DEVICE AND A SYNCHRONOUS RECTIFIER PCB - A power supply device includes a main unit and a power switching module. The main unit includes a primary circuit board, a transformer including a primary and a secondary coil, a primary-side circuit and a secondary-side circuit. The power switching module includes a separate PCB formed with at least two connection pads and two conductive tracks, and at least one power switching element disposed on the PCB and having two terminals respectively connected to the two connection pads through the two conductive tracks. The power switching module is in the form of a separate PCB that is electrically connected to the primary- or secondary-side circuits through the two connection pads. | 10-24-2013 |
20130294115 | CONTROL DRIVEN SYNCHRONOUS RECTIFIER SCHEME FOR ISOLATED ACTIVE CLAMP FORWARD POWER CONVERTERS - A synchronous rectification circuit includes a transformer receiving an input voltage at a primary side and outputting an output voltage at a secondary side and a controller arranged and programmed to operate independently from the input and output voltages. The controller preferably outputs control signals to switching logic devices, the switching logic devices being arranged to output timing signals to drive individual synchronous rectifiers included in the secondary side of the transformer. The synchronous rectification circuit includes at least one logic gate which receives the control signals output from the controller and supplies clock signals to the switching logic devices, the clock signals being generated by the at least one logic gate based on the control signal and driving devices arranged to receive the timing signals from a respective one of the switching logic devices, the driving devices driving the synchronous rectifiers in accordance with the timing signals. | 11-07-2013 |
20140085939 | High Efficiency Power Converter - A power converter nearly losslessly delivers energy and recovers energy from capacitors associated with controlled rectifiers in a secondary winding circuit, each controlled rectifier having a parallel uncontrolled rectifier. First and second primary switches in series with first and second primary windings, respectively, are turned on for a fixed duty cycle, each for approximately one half of the switching cycle. Switched transition times are short relative to the on-state and off-state times of the controlled rectifiers. The control inputs to the controlled rectifiers are cross-coupled from opposite secondary transformer windings. | 03-27-2014 |
20140140106 | ADAPTIVE DEAD TIME CONTROL SCHEME FOR SWITCH MODE POWER CONVERTER WITH SYNCHRONOUS RECTIFIERS TOPOLOGY - An adaptive dead time (ADT) control scheme for use with a switch mode power converter having a full bridge with synchronous rectifiers topology. A controller which implements the control scheme includes an input circuit arranged to receive a signal representative of the converter's output voltage, and an output circuit arranged to operate the converter's switching elements and synchronous rectifiers to produce a desired output voltage. The controller is further arranged such that the converter's “dead time” is adaptively varied in an inverse relationship to the magnitude of the load current. In a preferred embodiment, the signals used to operate the synchronous rectifiers are PWM signals, and the controller adaptively varies the dead time in a linear inverse relationship to the magnitude of the load current by modulating the rising and falling edges of the signals used to operate the synchronous rectifiers. | 05-22-2014 |
20140169042 | POWER SUPPLY DEVICE - A power supply device includes a primary circuit that includes two primary windings, a secondary circuit that includes two secondary windings and a switching element for synchronous rectification, a first transformer configured to couple one of the two primary windings with one of the two secondary windings, a second transformer configured to couple the other one of the two primary windings with the other one of the two secondary windings, and a first substrate on which both output ends of one of the two secondary windings and both output ends of the other one of the two secondary windings are disposed to face each other, wherein the switching element for synchronous rectification is disposed in a region between the first transformer and the second transformer on the first substrate. | 06-19-2014 |
20140192561 | CONTROL CIRCUIT FOR SWITCHING POWER CONVERTERS WITH SYNCHRONOUS RECTIFIERS - A control circuit for switching power converters with synchronous rectifiers is disclosed for providing start-up and shut-down protection. The control circuit for switching power converters with synchronous rectifiers includes a means for blocking the driving signals to the synchronous rectifiers, a voltage sampling circuit, a reference voltage, and a comparator. The comparator compares a sample voltage to a reference voltage to determine when to block and when to admit driving signals to the synchronous rectifiers. The control circuit for switching power converters with synchronous rectifiers is particularly useful for minimizing component damage due to start-up and shut-down transients as compared to converters known in the art. | 07-10-2014 |
20150109831 | SWITCHING POWER SUPPLY DEVICE - A drive control circuit for a switching power supply device. The drive control circuit includes an output control circuit configured to generate an output control signal with a pulse width corresponding to an output voltage of the switching power supply device, a threshold setting circuit configured to determine a winding threshold voltage according to a direct current input voltage applied to the series resonant circuit formed of the leakage inductance of an isolation transformer and a capacitor of the switching power supply device, a winding detection circuit configured to compare a voltage generated in a tertiary winding of the isolation transformer with the winding threshold voltage and to accordingly output a winding detection signal, and a drive circuit configured to receive the winding detection signal and the output control signal, and to generate a pulse-width controlled drive signal for driving a first switching element of the switching power supply device. | 04-23-2015 |
20150117068 | DRIVE CIRCUIT FOR SYNCHRONOUS RECTIFIER AND METHOD THEREOF - A power converter includes a primary side power circuit, a secondary side power circuit, and a synchronous rectifier drive circuit. The primary side power circuit includes a primary winding and a main switch coupled in series. The main switch is turned on and off in response to control signals. The secondary side power circuit includes a secondary winding, at least one synchronous rectifier switch, and an output inductor winding. The secondary winding is inductively coupled to the primary winding and forms a first magnetic coupling with the primary winding. The synchronous rectifier drive circuit includes a first and a second auxiliary winding coupled in series. The first auxiliary winding is inductively coupled to the primary winding and forms a second magnetic coupling with the primary winding. The second auxiliary winding is inductively coupled to the output inductor winding and forms a third magnetic coupling with the output inductor winding. | 04-30-2015 |
20150372605 | CONTROLLING A SWITCHED MODE POWER SUPPLY WITH MAXIMISED POWER EFFICIENCY - A control circuit operable to generate a control signal to control the duty cycle of a switched mode power supply is provided. The control circuit comprises an input terminal for receiving a signal indicative of an input voltage (V | 12-24-2015 |
20160013725 | High Efficiency Power Converter | 01-14-2016 |
20160028319 | SELF-DRIVEN SYNCHRONOUS RECTIFICATION FOR A POWER CONVERTER - A power converter with an isolated topology may include a power transistor, a sense transistor, and a read-out circuit. The sense transistor may be arranged in a current mirror configuration with the power transistor such that the gate terminal of the sense transistor is coupled to the gate terminal of the power transistor and the first drain/source terminal of the sense transistor is coupled to the first drain/source terminal of the power transistor. The read-out circuit may be coupled to the second drain/source terminal of the power transistor and the second drain source/terminal of the sense transistor. The read-out circuit may be arranged to cause a voltage at the second drain/source terminal of the sense transistor to be substantially the same as a voltage at the second drain/source terminal of the power transistor. | 01-28-2016 |
20160036337 | SWITCHING POWER SUPPLY APPARATUS - A switching power supply apparatus includes a first series circuit including a third rectifier device and a fourth rectifier device and that is connected between a positive output terminal and a negative output terminal, and a first capacitor a first end of which is connected to a connection node between the third rectifier device and the fourth rectifier device and a second end of which is connected to an end, not connected to the first series circuit, of a first rectifier device or a second rectifier device. The first series circuit and the first capacitor define a snubber circuit. | 02-04-2016 |
20160079870 | SWITCHING POWER SUPPLY CIRCUIT - A switching power supply device includes: a transformer; a first switch connected between a high potential terminal of an input DC voltage source and a primary winding; a second switch connected between a low potential terminal of the input DC voltage source and a primary winding; a control circuit outputting a driving pulse signal for synchronizing the first and second switches; first and second rectifying devices; a synchronous rectifier circuit; and a positive bias circuit that applies a positive bias to a control terminal of one of the first and second switches so as to constantly turn the one of the first and second switches ON. When the first and second switches stop a switching operation while an output voltage exists between the output terminals, the positive bias circuit applies the positive bias to the one of the first and second switches. | 03-17-2016 |
20160079871 | SWITCHING POWER SUPPLY CIRCUIT - A switching power supply device includes: a main transformer; a main switch that is connected between a high potential terminal of an input direct current voltage source and a primary-side main winding; a synchronous rectifier circuit includes: a rectifying switch that is connected to a secondary-side main winding in series and that is turned ON in synchronization with a turning ON state of the main switch and a commutation switch that is connected to the rectifying switch series circuit in parallel and that is turned ON in synchronization with a turning OFF state of the main switch; and an auxiliary switch circuit that turns the commutation switch OFF. When the main switch stops a switching operation while a voltage exists at a first output terminal on a high potential side, the auxiliary switch circuit turns the commutation switch OFF to prevent continuation of self-excited oscillation. | 03-17-2016 |
20160087541 | MINIMUM DUTY CYCLE CONTROL FOR ACTIVE SNUBBER - This application provides methods and apparatus for controlling aspects of a synchronous rectifier power converter. In an example, an apparatus can include a minimum duty cycle control circuit configured to receive first control signals for one or more switches associated with the synchronous rectifier power converter, to compare a duty cycle of the first control signals to a minimum duty cycle threshold, and to provide second control signals having at least the minimum duty cycle for an active snubber switch of the synchronous rectifier power converter. | 03-24-2016 |
20160094132 | Optimum Offline Converter Control Using Intelligent Power Processing - Intelligent control methods are shown that increase efficiency and reduce standby power and start up power requirements | 03-31-2016 |
20160111966 | EMBEDDED MAGNETIC COMPONENT TRANSFORMER DEVICE - An embedded transformer device includes first, second, and auxiliary windings, defined in an insulating substrate by conductive vias joined together by conductive traces. The positions of the conductive vias are arranged to optimize the isolation properties of the transformer, while the conductive traces are arranged to optimize the coupling between the primary and secondary side windings. The embedded transformer device provides favourable isolation and energy transfer between input side and output side windings, in a device with a small component size. | 04-21-2016 |
20160149502 | BIDIRECTIONAL DC/DC CONVERTER, AND BIDIRECTIONAL POWER CONVERTER - In a discharging operation of a vehicle storage battery, a controller switches between a full-wave rectification operation of full-wave rectify a voltage across a second winding while maintaining a second short circuit in an open state, and a full-wave voltage doubling rectification operation of full-wave voltage doubling rectify a voltage across second winding while maintaining second short circuit in a closed state, based on magnitude relationship between DC voltage across first terminals and DC voltage across second terminals. In a charging operation, controller switches between a full-wave rectification operation of full-wave rectify a voltage across a first winding while maintaining a first short circuit in an open state, and a full-wave voltage doubling rectification operation of full-wave voltage doubling rectify a voltage across first winding while maintaining first short circuit in a closed state, based on magnitude relationship between DC voltage across first terminals and DC voltage across second terminals. | 05-26-2016 |
20160172987 | DC-DC CONVERTER FOR BATTERY SYSTEM WITH WIDE OPERATING VOLTAGE RANGE | 06-16-2016 |
20160190943 | Switched-Capacitor Split Drive Transformer Power Conversion Circuit - A split drive transformer (SDT) and use of such a transformer in a power converter is described. The power converter includes a power and distributor circuit configured to receive one or more input signals and provides multiple signals to a first side of the SDT. The SDT receives the signals provided to the first side thereof and provides signals at a second side thereof to a power combiner and rectifier circuit which is configured to provide output signals to a load. In some embodiments, the SDT may be provided as a switched-capacitor (SC) SDT. In some embodiments, the power converter may optionally include a level selection circuit (LSC) on one or both of the distributor and combiner sides. | 06-30-2016 |
20220140743 | SWITCHING-TYPE REGULATION DRIVER AND REGULATION DRIVING METHOD THEREOF - A switching-type regulation driver comprises a transformer, a controller, a synchronous rectifier and a drive control module. The drive control module is connected to the synchronous rectifier and the non-homonymous end of the secondary winding respectively, and is used to detect a target parameter of the voltage at both power ends of the synchronous rectifier when the synchronous rectifier disconnects the conductive path between the non-homonymous end of the secondary winding and the reference ground. When it is detected that the target parameter of the voltage at both power ends of the synchronous rectifier meets a preset condition, the controller controls a switching action of the first transistor so that the primary winding transmits power to the secondary winding. According to the present disclosure, the pre-stage chip may be matched with to realize a function of dynamic acceleration, and the dependence on the output pin may be reduced. | 05-05-2022 |