Abstract: Auto-compensation—for compensating voltage regulators generating a regulated output voltage—may be performed dynamically by determining various coefficients of a compensation function used in compensating the power regulator, based at least on assumptions about the structure of the regulator and corresponding filters. At least the DC loop gain and the position of the compensation zeros may be determined without requiring any prior knowledge of the values of the various components of the system. The compensator coefficients may be adjusted based on duty-cycle jitter information, which may be accurately obtained/measured at a high signal-to-noise ratio. By observing the duty-cycle jitter, the capacitor (equivalent series resistance) may be optimally compensated by tuning the 0 dB crossover slope of the loop gain. Accordingly, auto-compensation may be performed by measuring the duty-cycle jitter while maintaining optimum stability and transient performance.

Abstract: An adapter includes a rectifying unit, a power factor correction unit, a standby circuit, a load-connecting detection circuit, a first power conversion circuit, a second power conversion circuit and an auxiliary voltage control circuit. When a load apparatus is connected to the adapter, a first ground side of the first power conversion circuit is short-circuited to a second ground side of the second power conversion circuit, so that the load-connecting detection circuit is turned on and sends out a first signal. After the auxiliary voltage control circuit receives the first signal, the auxiliary voltage control circuit is turned on to drive the first power conversion circuit and the second power conversion circuit, so that the first power conversion circuit and the second power conversion circuit start to convert a first voltage into a first output voltage and a second output voltage.

Abstract: Upper arm connection sections and lower arm connection sections are provided in parallel. An upper arm transformer and a power supply are provided in an area opposed to the lower arm connection sections with respect to the upper arm connection sections. A power supply control section is provided in at least one of an area opposed to the upper arm connection sections with respect to the upper arm transformer, and an area which is sandwiched between at least one of the upper and lower connection sections closest to one side of the substrate positioned in a direction in which the upper arm connection sections are arranged, and the one side. The lower arm transformer is provided in an area opposed to the upper arm connection sections with respect to the lower arm connection sections. The lower arm transformer is common to at least two of the lower arm switching elements.

Abstract: A power conversion device includes a power conversion circuit having first, second, third, and fourth switches, and a controller. The controller generates a first pulse signal for controlling the turning on and off of the first and fourth switches and a second pulse signal for controlling the turning on and off of the second and third switches, based on a circuit current flowing in the power conversion circuit and a voltage of an AC power source. The turning on and off of the switches causes the power conversion device to have a flowing current in which a high frequency component is mixed with a low frequency component.

Abstract: Methods, systems and apparatuses for voltage regulation are disclosed. For an embodiment, a voltage regulator includes a power source block configured to convert an input voltage to an output voltage to supply current to an output load, a storage capacitor, and an active filter configured to transfer energy between the output load and the storage capacitor. A conversion ratio of the active filter is controlled by a parameter related to the output voltage, and a conversion ratio of the power source block is at least partially controlled by a parameter related to the voltage on the storage capacitor.

Abstract: Disclosed is a battery and load equalization circuit that prevents the in-rush of current when batteries and/or loads are initially connected in parallel. Various techniques are used including charging, discharging and use of DC to DC converters to equalize charges between batteries and between batteries and capacitive loads.

Abstract: Disclosed are a wireless power transmitting apparatus and a method thereof. The wireless power transmitting apparatus wirelessly transmits power to a wireless power receiving apparatus. The wireless power transmitting apparatus detects a wireless power transmission state between the wireless power transmitting apparatus and the wireless power receiving apparatus, and generates a control signal to control transmit power based on the detected wireless power transmission state. The wireless power transmitting apparatus generates the transmit power by using first DC power based on the control signal, and transmits the transmit power to a transmission resonance coil through a transmission induction coil unit based on an electromagnetic induction scheme.

Abstract: A power converter includes inverters, AC sides of the inverters being connected in parallel, and a controller configured to control total output power of the inverters by controlling output power of at least one of the inverters in a control cycle shorter than a shortest communication cycle which allows communication with each of the inverters.

Abstract: This invention is concerning a power supply device that includes a cut-off unit configured to cut off voltage to be applied to a primary winding of a transformer and a coil added in series with the primary winding of the transformer, a first circuit configured to cause, in a case where the voltage to be applied is cut off by the cut-off unit, current to flow in such a way that energy accumulated in the transformer is led to a capacitor, and a second circuit configured to clamp, in a case where the voltage to be applied is cut off by the cut-off unit, voltage of the primary winding and the coil.

Abstract: A system for testing over-current fault detection includes a first switch to connect a voltage to a load and a capacitor; a first monitor circuit that monitors a current from the first switch to the load; a second monitor circuit that monitors a voltage across the capacitor; and a microcontroller configured to control a state of the first switch to connect voltage to the load and verifies over-current detection based upon current generated during charging of the capacitor. The microcontroller detects an over-current fault condition based upon input from the first monitor circuit and detects a short-circuit fault condition based upon input from the second monitor circuit during test of the first monitor circuit.

Abstract: A voltage measuring apparatus is configured to measure voltage between a positive terminal and a negative terminal of a device, and the voltage measuring apparatus includes: a PTC thermistor that is connected to one of terminals of the device; and a measuring circuit that measures voltage of one of the terminals through the PTC thermistor with respect to a specified reference potential and voltage of the other of the terminals with respect to the reference potential. The voltage measuring apparatus detects temperature abnormality of the device or components associated with the device.

Abstract: A switching power supply apparatus includes: a dead time circuit that receives an output control signal and generates dead time signal to specify a time width when both first and second switching elements are turned OFF; an output signal generation circuit that generates first and second output signals which specify the ON time of the first and second switching elements respectively in accordance with the output control signal and the dead time signal; and a dead time adjustment circuit that adjusts the turn ON timings of the first and second switching elements by changing the time width of the dead time signal in accordance with the change of voltage of the DC input power or the change of the output voltage of the capacitor.

Abstract: Provided are a power supply device capable of supplying required power even during standby and an electrical apparatus. A power supply device includes a current resonant circuit configured to drive a transformer and a resonant circuit using a switching element, the resonant circuit being connected to a primary side of the transformer, the switching element being periodically repeatedly turned on and off, and a controller configured to control the switching element so that the switching element performs a continuous operation in which the switching element is turned on and off continuously repeatedly or an intermittent operation in which the switching element is turned on and off intermittently repeatedly, in accordance with an external signal indicating the continuous operation or the intermittent operation.

Abstract: An energy-saving power supply apparatus includes a bridge rectifier, a diode bypass circuit and a control circuit. The diode bypass circuit is electrically connected to the bridge rectifier. The control circuit is electrically connected to the diode bypass circuit and the bridge rectifier. The bridge rectifier includes a plurality of diodes. After the control circuit receives a power start signal, the control circuit is configured to control the diode bypass circuit, so that a part of the diodes are bypassed to save energy.

Abstract: Disclosed is a ?uk based current source, a control circuit for a ?uk based current source, and a method for providing a current.

Abstract: The present application discloses a device for wireless charging circuit, comprising: a primary circuit box, which comprises at least one first switch unit; a secondary circuit box, which comprises at least one second switch unit; a transmission plate, which comprises a primary inductor of a transformer and a primary compensation capacitor, the primary inductor being coupled in series with the primary compensation capacitor; a receiving plate, which comprises a secondary inductor of the transformer; the transmission plate and the receiving plate are magnetically coupled with each other; the transmission plate is coupled with the primary circuit box; and the receiving plate is coupled with the secondary circuit box. The voltage between external terminals of transmission plate and the voltage between external terminals of receiving plate can satisfy the safety requirement.

Abstract: An energy efficient apparatus includes a switching device, a frequency dependent reactive device, and a control element is provided. The switching device is coupled to a source of electrical power and includes a pair of transistors and is adapted to receive a control signal and to produce an alternating current power signal. The frequency of the alternating current power signal is responsive to the control signal. The frequency dependent reactive device is electrically coupled to the pair of transistors for receiving the alternating current power signal and producing an output power signal. The frequency dependent reactive device is chosen to achieve a desired voltage of the output power signal relative to the frequency of the alternating current power signal. The control element senses an actual voltage of the direct current power signal and modifies the control signal delivered to achieve the desired voltage of the direct current power signal.

Abstract: A switching power-supply circuit includes a second rectifying/smoothing circuit arranged to generate a second output voltage by rectifying and smoothing the output of a second secondary winding, and the second rectifying/smoothing circuit includes a second rectifier circuit and a capacitor, connected to the second secondary winding. A second switching control circuit operates in response to an alternating-current winding voltage occurring in the second secondary winding, and includes a time constant circuit causing a switch mechanism connected to the control terminal of a rectifier switch element to operate, and a second feedback circuit arranged to detect and feed back the second output voltage to the time constant circuit.

Abstract: Discussed are a power conversion apparatus and a photovoltaic module including the power conversion apparatus. The power conversion apparatus includes a converter unit to convert DC voltage from a solar cell module, the converter unit including a plurality of interleaving converters, and a controller to control the converter unit, wherein the controller changes switching periods of the interleaving converters and changes phase differences between the interleaving converters during operation sections of the interleaving converters, in response to a change of the switching periods of the interleaving converters. Consequently, it is possible to prevent instantaneous reduction of output power due to change of switching frequencies of the interleaving converters.

Abstract: A switching power source device according to one aspect of the present invention is a current-resonant DC-DC converter, and includes a control integrated circuit having an oscillation circuit that determines a switching frequency of switching elements and a burst control circuit that controls a burst operation in the standby mode, as well as an output voltage detecting unit connected to a secondary side of a transformer to detect an output voltage. The switching frequency of the switching element is determined by the oscillation circuit by the smaller of a first frequency control voltage generated from a voltage of an auxiliary coil disposed in the primary side of the transformer and a second frequency control voltage corresponding to the output voltage, and the burst control circuit generates the first frequency control voltage that gradually increases or decreases in accordance with the voltage of the auxiliary coil.

Abstract: In accordance with an embodiment, a method of operating a switched-mode power supply includes starting up the switched-mode power supply by applying a first switching signal to a control node of the first switching transistor and a second switching signal to a control node of a second switching transistor, where a duty cycle of the first switching signal is less than a duty cycle of the second switching signal. After starting up the switched mode power supply, the switched mode power supply is operated by applying a third switching signal to the control node of the first switching transistor and a fourth switching signal to the control node of the second switching transistor, where a duty cycle of the third switching signal is substantially equal to a duty cycle of the fourth switching signal.

Abstract: Thermally protected bleeder circuits for maintaining an input current of a power converter above a dimmer circuit holding current are disclosed. In one example, a bleeder control circuit may generate a bleeder control signal to control a bleeder current of the bleeder circuit based on an input current signal and a temperature signal. The bleeder control circuit may cause the bleeder current to be substantially equal to zero in response to the input current signal being greater than or equal to a reference signal, and may cause the bleeder current to be proportional to a difference between the input current signal and the reference signal in response to the input current signal being less than the reference signal. The reference signal may be constant for temperatures less than a threshold temperature, but may decrease with respect to increases in temperature for temperatures greater than the threshold temperature.

Abstract: A method includes comparing, by a voltage-second (VS) controller, a first duty cycle used to control a first switch at a primary side of a power transformer of a DC-to-DC converter with a threshold. The method further includes if a value of the first duty cycle is less than the threshold, controlling, by the VS controller, a second duty cycle used to control a second switch at a secondary side of the power transformer, and maintaining a voltage level at an output voltage node at a non-zero value, and if the value of the first duty cycle is greater than the threshold, controlling, by an output voltage loop, the second duty cycle based on the first duty cycle, and monotonically increasing the voltage level the at the output voltage node from the non-zero value to a predetermined value.

Abstract: Methods and systems for calibrating an inductor-inductor-capacitor (LLC) resonant converter are provided herein. The method includes calculating input voltage mathematically as a function of at least one of an output voltage, a load current, and tolerances of components of the LLC resonant converter and operating the LLC resonant converter in an open loop mode at a nominal resonant frequency. The method also includes measuring output voltage of the LLC resonant converter and comparing the measured output voltage to the calculated input voltage.

Abstract: The present invention relates to a converter for transferring power between a first DC system of DC voltage V1 and a second DC system of DC voltage V2, the converter comprising: —a first AC/DC converter for transforming DC voltage V1 into a first single phase AC voltage V1ac, of frequency ?, root mean square line-neutral magnitude V1acm and angle ?1; a second AC/DC converter for transforming DC voltage V2 into a second single phase AC voltage V2ac, of frequency ?, root mean square line-neutral magnitude V2acm and angle ?2; and two inductors L1, L2 and a capacitor C, wherein the first terminals of the inductors and capacitor are connected together, the second terminal of inductor L1 and the second terminal of the capacitor C are connected to the first AC voltage V1ac, and the second terminal of inductor L2 and the second terminal of the capacitor C are connected to the second AC voltage V2ac; wherein the value of the capacitor C, inductor L1 and inductor L2 are selected to enable required power transfer and to

Abstract: A peak efficiency detection system may include a switched power supply (SPS) module providing an output supply signal. The SPS module may have an internal node, and a plurality of SPS circuits configured to generate the output supply signal on the internal node. A dead type module may generate control signals. A central node external to the SPS module may deliver the output supply signal to a load module. A power stage size control module may generate control signals for controlling the SPS module. A peak-efficiency detection (PED) module may receive the output supply signal from the central node, the control signals from the SPS module, and the control signals from the power stage size control module. The PED module may generate a signal representative of an efficiency of the SPS module.

Abstract: A hybrid distribution transformer is provided that includes an electromagnetic transformer and a voltage source converter that is operable to reduce fluctuation in the output voltage of the hybrid distribution transformer in the event of an increase or decrease in the input voltage.

Abstract: A system for cooling air includes an air cooling apparatus that includes an intermediate ducted section with two movable dampers separated by a divider containing a heat exchange element. The heat exchange element can be situated parallel to a direction of airflow in the air cooling apparatus, such that opening both dampers can cause a flow of air to bypass the apparatus and closing both dampers can force the air to pass through the heat exchange element.

Abstract: An inverting apparatus and a control method thereof are provided. The inverting apparatus includes an inverting circuit, a capacitor, and a control circuit. The inverting circuit receives a DC input power and is configured to convert the DC input power into an AC output power, wherein an AC output current of the AC output power is preset to a preset output current. The capacitor is connected to an output terminal of the inverting circuit. The control circuit is coupled to the inverting circuit and is configured to control a power conversion of the inverting circuit, wherein the control circuit superimposes a preset capacitor compensation current of which the phase leads to the preset output current on the preset output current, so as to control the inverting circuit to adjust the AC output current and provide the adjusted AC output current to a power grid.

Abstract: A DC to DC converter assembly, for connecting first and second high voltage DC power transmission networks, comprising first and second modular multilevel converters, each converter including a first converter limb having first and second limb portions, each limb portion including a least one module switchable to selectively provide a voltage source and thereby vary the magnitude ratio of a DC voltage (V1, V2) across the first and second terminals of a respective converter and an AC voltage (VAC) at the third terminal of the corresponding converter, the DC to DC converter assembly further including a first link electrically connecting the third terminal of one converter, with the third terminal of the other converter, and at least one converter further including a controller configured to switch the first and second limb portions in the first converter limb of the said converter into simultaneous conduction to divert a portion (IDiV1) of current flowing within the said converter away from the first link.

Abstract: An energy harvesting apparatus includes: a capacitor configured to store energy generated by an energy harvesting element; and a switch connected to the capacitor and configured to switch energy supply from the capacitor to a load based on a capacitor voltage with which the capacitor is charged. An energy harvesting system includes: energy harvesting elements; energy harvesting apparatuses which are provided to respectively correspond to the energy harvesting elements; and a load as an energy supply destination connected to the energy harvesting apparatuses.

Abstract: Disclosed are an isolated power converter and a switching control signal using the same. In the isolated power converter, the positions of the power switch and the primary winding are exchanged, and the feedback voltage detection and secondary current zero-crossing detection are carried out in accordance with the voltage across the primary winding. Thus, primary side control can still be implemented without employment of an auxiliary winding.

Abstract: A soft-switching and low input current ripple power inversion circuit, in which the inversion circuit is connected in parallel to an input DC voltage source and includes a top cell, a bottom cell and at least one transformer, in which the top cell and the bottom cell have its individual impedance adjusting unit of which the impedance can easily be adjusted to obtain the required equivalent resonant inductance or capacitance. Thus, the semiconducting switches therein can be soft-switched alternately to reduce the switching loss. Moreover, the inversion circuit can be modified by adding at least one middle cell inserted between the top cell and the bottom cell to reduce the voltage stress on the semiconductor switch. Consequently, low voltage rating semiconductor switch accompanied with lower RDS(on), conduction losses can be reduced to improve the converter efficiency.

Abstract: A biasing and driving circuit for an electric load, having an input adapted to receive an a.c. input voltage and an output adapted to supply a d.c. output voltage, comprising: a voltage-regulator device, having a feedback input terminal configured to receive a sensing voltage that is a function of a supply current that flows through the electric load and regulating, on the basis of the sensing voltage received, the supply current; a resistive sensing element, operatively coupled to the feedback input, configured to receive the supply current and generate the sensing voltage as a function of the supply current; a resistor coupled to the feedback input; and an auxiliary biasing circuit adapted to receive the a.c. input voltage and inject through the resistor an a.c. auxiliary biasing current that varies in a way inversely proportional to the input voltage.

Abstract: A semiconductor driving device includes a negative surge detection circuit and a level shifter circuit. The negative surge detection circuit detects whether the negative surge occurs at a connection point between a P-side SW element and N-side SW element. The level shifter circuit maintains a driving voltage used in driving the P-side SW element upon the negative surge detection circuit detecting occurrence of the negative surge.

Abstract: A power supply circuit includes a plurality of output terminals that output voltages (voltages may have the same or different voltage values among the output terminals), and a transformer that has a plurality of output windings. First and second output windings of the plurality of output windings are coupled to each other. The first and second output windings have the same number of turns. First terminals, which have a first polarity, of the first and second output windings are connected to each other via a capacitor. Further, second terminals, which have a second polarity opposite to the first polarity, of the first and second output windings are electrically connected to each other. The second terminals of the first and second output windings may be directly connected to each other.

Abstract: A method and apparatus for converting a first power to a second power. In one embodiment the apparatus comprises a power conversion circuit for receiving the first power; and a controller, coupled to the power conversion circuit, for dynamically selecting between a non-interleaved mode and an interleaved mode for operating the power conversion circuit to convert the first power to the second power.

Abstract: A semiconductor device having high breakdown withstand voltage includes a first element which is a normally-on type transistor made of nitride compound semiconductor, a second element which is connected to the first element in series and is a transistor having withstand voltage between a source and a drain lower than withstand voltage of the first element, a first diode which is connected between a gate of the first element or a gate of the second element and a drain of the first element so that a cathode of the first diode is connected at the drain's side and has predetermined avalanche withstand voltage, and a first resistance connected to the gate to which the first diode is connected. The avalanche withstand voltage of the first diode is lower than breakdown voltage of the first element.

Abstract: An RF electronics module includes a grounding plate, a non-conductive substrate, a number of conductive vias, RF PA circuitry, and RF power detection circuitry. The non-conductive substrate is over the grounding plate. The conductive vias extend parallel to one another from a surface of the non-conductive substrate opposite the grounding plate through the non-conductive substrate to the grounding plate. The RF PA circuitry is coupled to the grounding plate through a first one of the conductive vias. The RF power detection circuitry is coupled to a second one of the conductive vias and configured to measure a signal induced in the second one of the conductive vias due to electromagnetic coupling with the first one of conductive vias. The first one of the conductive vias is adjacent to the second one of the conductive vias.

Abstract: A current resonance type DC-DC converter includes a transformer that has a primary winding and a secondary winding, a switching circuit that has a pair of first switching elements and that is connected to the primary winding, an AC/DC transfer circuit that has four rectifying devices, which are connected in full bridge and include a pair of second switching elements, that is connected to the secondary winding, that converts an AC voltage, which is induced at the secondary winding, into a DC voltage and that outputs the DC voltage, and a control circuit that controls ON and OFF operations of the pairs of the first and second switching elements. The control circuit controls the ON and OFF operations so as to synchronize the pair of the first switching elements with the pair of the second switching elements.

Abstract: Various computing devices and methods of managing the power consumption thereby are disclosed. In one aspect, a method of managing power consumption of a computing device that has a battery is provided. The method includes cycling the computing device between a connected standby active state and a connected standby idle state. The duration of the connected standby idle state is set based at least in part on a charge level of the battery.

Abstract: In one embodiment, a method of controlling a capacitor discharge for a switching power supply, can include: (i) generating a first voltage signal from a voltage at an X capacitor that is coupled between input terminals of the switching power supply; (ii) activating a detection signal in response to the first voltage signal being inactive for a duration of a predetermined time interval, where the detection signal being activated indicates a cut-off of the input terminals; and (iii) at least partially discharging the X capacitor after the cut-off and in response to activation of the detection signal.

Abstract: A power converter having a current limit module and a method for controlling the power converter. The power converter converts an input voltage to an output voltage based at least on driving a main switch to switch on and off and regulates the output voltage through regulating a duty cycle of the main switch. The current limit module is configured to compensate a first current limit threshold indicative of a maximum allowable value of a peak value of a switching current of the main switch with a threshold compensation signal indicative of the duty cycle to provide a second current limit threshold. The second current limit threshold is used to limit the maximum value of the peak value, so that a maximum allowable output power of the power converter is substantially uninfluenced by the variation in the duty cycle.

Abstract: Provided is a received power conversion device for a resonant wireless charging system, including a wireless power receiver for receiving wireless power from a wireless power transmission device, a rectifier for rectifying power in an Alternating Current (AC) form received in the wireless power receiver into a Direct Current (DC), a free-wheeling switching unit for switching according to a switching control signal to form a path for free-wheeling the power in the AC form, a feedback circuit fed back with an output signal of a corresponding power conversion device to detect a level of the output signal, and a controller for controlling switching of the free-wheeling switching unit according to the output level detected by the feedback circuit.

Abstract: The disclosed embodiments provide an AC/DC power converter that converts an AC input voltage into a DC output voltage. This AC/DC power converter includes an input rectifier stage which rectifies an AC input voltage into a first rectified voltage. The AC/DC power converter also includes a switching resonant stage which is directly coupled to the output of the input rectifier stage. The switching resonant stage converts the rectified voltage into a first high frequency AC voltage of a first amplitude. This AC/DC power converter additionally includes a transformer which is coupled to the output of the switching resonant stage and is configured to down-convert the first high frequency AC voltage into a second high frequency AC voltage of a second amplitude. Furthermore, the AC/DC power converter includes an output rectifier stage which is coupled to the output of the transformer, wherein the output rectifier stage rectifies the second high frequency AC voltage into a DC output voltage.

Abstract: There is provided a power supply apparatus capable of precisely control a primary side switching frequency at a secondary side by receiving fed-back information regarding a power state at the secondary side without a separate expensive circuit or a complicated circuit. The power supply apparatus includes: a power supplying unit having a primary side and a secondary side having different ground electrical characteristics, switching power input to the primary side, and transferring the switched power to the second side electrically insulated from the primary side to supply the power; a controlling unit provided on the secondary side and receiving fed-back information regarding a power state of the power supplying unit to control a maximum value and a minimum value of a switching frequency of the primary side; and a transferring unit transferring a control signal from the controlling unit to the primary side of the power supplying unit.

Abstract: The present invention related to a switch control circuit, a coupled inductor boost converter including the same, and a driving method thereof. The coupled inductor boost converter includes a first inductor connected between an input voltage and a first node, a second inductor connected between the first node and a second node, and a power switch connected between the first node and a ground, and a switch control circuit. The switch control circuit receives a voltage of the second node and turn on the power switch by using the voltage of the second node at a time when a voltage of the first node becomes a zero voltage.

Abstract: There is provided a power supply including a direct current (DC) to DC converter supplying main power to a load, and a sub converter connected to the DC to DC converter and reducing output loss, wherein the sub converter is operable based on a hold-up time.

Abstract: In a power supply device, a primary winding of a transformer is connected in series to a main switching element, and is connected in parallel to a series circuit of a resonance capacitor and a sub switching element. A secondary winding of the transformer is connected in series to a series circuit of a rectifying element and a resonance inductor. The capacitance of the resonance capacitor and the inductance of the resonance inductor are each set such that, when the sub switching element is in an on state, the waveform of the voltage that is generated between the first main terminal and the second main terminal of the main switching element takes a protruding curve shape, the voltage being generated due to a resonance phenomenon of at least the resonance capacitor and the resonance inductor.

Abstract: An interleaved forward voltage converter having a first inverter stage has a first transformer having a first secondary winding coupled to a filter inductor. A second converter stage has a second transformer having a second secondary winding coupled to the filter inductor. A diode is coupled between the first and second secondary windings to automatically connect the first and second secondary windings in series when a duty cycle of the converter exceeds 50%. An interleaved forward voltage converter can connect the two primary windings in either parallel or a series configuration. The two secondary windings can be connected in either parallel or a series configuration. Having the two primary windings in parallel and the two secondary windings in series allows the converter to operate with a lower input voltage. Having the two primary windings in series and the two secondary windings in a parallel configuration allows the converter to operate with a higher input voltage.