444 results about "Synchronous rectifier" patented technology

Disclosed are a synchronous rectification control circuit, a synchronous rectification control method and a switching power supply, the synchronous rectification control circuit comprising: a volt-second setting unit for processing a volt-second product reference value into at least any two of a first volt-second product threshold to a third volt-second product threshold; the first control driving unit is used for sending a first conduction signal to conduct the synchronous rectifier tube and controlling the pulse width of the first conduction signal according to a first volt-second product threshold value; the second control driving unit is used for calculating a first volt-second product of voltages at two ends of the secondary winding within first time after the first conduction signal is generated, and controlling the synchronous rectifier tube to be conducted for follow current after the first volt-second product is greater than a second volt-second product threshold value; and the voltage judgment unit is used for calculating a second volt-second product of voltages at two ends of the secondary winding within a second time after the first conduction signal is generated, and judging the state of the input voltage according to the second volt-second product and a third volt-second product threshold value. Through the arrangement, the volt-second setting pin of the synchronous rectification control circuit can be reused to execute various functions.

A power converter incorporating a synchronous rectifier implements adaptive gate voltage regulation for fast turn-off of the synchronous rectifier. In some embodiments, the adaptive gate voltage regulation circuit and method monitors the slope of the synchronous rectifier current during the on period of the synchronous rectifier. In response to detecting the synchronous rectifier current decreasing rapidly, a larger gate discharge current is applied to quickly discharge the synchronous rectifier gate voltage. In response to detecting the synchronous rectifier current decreasing more moderately, a smaller gate discharge current is applied to discharge the synchronous rectifier gate voltage in a moderate manner. When the synchronous rectifier can be turned off quickly, large reverse current and large drain voltage spike at the synchronous rectifier is avoided. The adaptive gate voltage regulation circuit and method is particularly useful when the power converter is operated in the discontinuous conduction mode.

System and method for controlling synchronous rectification. For example, a system for controlling synchronous rectification includes: a first control-signal generator configured to generate a first control signal; a second control-signal generator configured to receive the first control signal for a first switching cycle and generate a second control signal for a second switching cycle based at least in part on the first control signal for the first switching cycle, the first switching cycle preceding the second switching cycle; and a driver configured to receive the first control signal and generate a drive voltage based at least in part on the first control signal; wherein the second control-signal generator is further configured to: process information associated with the first control signal; determine a first time duration when the first control signal remains at a first logic level during the first switching cycle.

Disclosed in the present invention is a dual-path flyback DCDC auxiliary power supply with a low cross regulation rate and lossless absorption. The auxiliary power supply comprises a DC power supply, a first capacitor, a primary-side leakage inductance lossless absorption circuit, a transformer, and a secondary-side synchronous rectification current balancing circuit connected in sequence; the transformer comprises a primary-side primary winding NP1, a primary-side secondary winding NP2, a secondary-side primary feedback winding NS1, and a secondary-side secondary feedback winding NS2; the primary-side leakage inductance lossless absorption circuit comprises a first switching transistor, a diode, a second capacitor, a leakage inductor, an excitation inductor, and a primary-side secondary winding NP2; the secondary-side synchronous rectification current balancing circuit comprises a second synchronous rectifier, a third synchronous rectifier, a third capacitor, a fourth capacitor, a first load, and a second load. By means of the circuit design, the use of the primary-side leakage inductance lossless absorption circuit reduces the circuit loss and improves the power supply efficiency; and average energy distribution is realized by means of the control of the two synchronous rectifiers, thereby reducing the power supply cross regulation rate.

A flyback converter to receive an input voltage and provide an output voltage is provided, and may include a transformer having a primary winding and secondary winding, a primary switch coupled to the primary winding, a synchronous rectifier device coupled to the secondary winding, and a secondary side control circuit to turn on the synchronous rectifier device by outputting a control signal at a first amplitude, subsequently modify the control signal to maintain a voltage across the synchronous rectifier device substantially constant until a predicted time that precedes a current in the synchronous rectifier device reaching substantially zero, subsequently turn off the synchronous rectifier device based on the voltage across the synchronous rectifier device reaching substantially zero, and subsequently turn on the synchronous rectifier device by outputting the control signal at a second amplitude, before the primary switch is turned on. The second amplitude is less than the first amplitude.

A flyback-converter with synchronous-rectifier (SR) sense architecture is provided. A secondary side controller includes a SR-sense pin coupled through an external resistor to a drain of an SR on the secondary-side, a negative-sensing-detector, a peak-detector, a zero-crossing-detector, all coupled to the pin, and a resistor network (Rn) coupled between the pin and ground. The Rn includes a first resistor (R1) to couple the pin and to ground through a first switch (S1) during negative-sensing to divide a voltage (VSR_drain) coupled to the pin, and a second, higher resistance resistor (R2) to couple the pin to ground through a second switch (S2) during peak-detection to divide VSR_draincoupled to the pin. S1 and S2 are controlled by register-transfer-level circuit in the SSC. A line-feed-forward (LFF) circuit is coupled to the pin through an active diode to receive an undivided VSR_drain and mirrors diode current to control the converter in LFF mode.

The present invention provides a control circuit of an isolated power supply and an isolated power supply. A secondary side controller in the control circuit can turn on and off a synchronous rectifier based on a voltage from a secondary side winding, enabling adaptive turn-on and turn-off control of the synchronous rectifier. Specifically, when the voltage from the secondary side winding reaches a second predetermined voltage, an instruction for turning off the synchronous rectifier is provided. The second predetermined voltage is adjusted based on a comparison between a time interval for the previous switching period and a predetermined reference interval. In this way, a delay from a turn-off time of the synchronous rectifier to a turn-on time of a primary transistor switch is substantially maintained at the predetermined reference interval. This prevents cross-conduction of the primary and secondary side circuits, ensuring safe operation of the isolated power supply.

The embodiments of the present disclosure provide a synchronous rectifier module, comprising: a transformer provided with a plurality of secondary windings, a first circuit board and a second circuit board disposed on opposite sides of the transformer, and a first connecting piece electrically connected to the first circuit board and a second connecting piece electrically connected to the second circuit board; the first connecting piece and the second connecting piece comprise current sharing portions connected to the first circuit board and the second circuit board respectively, and inductor portions which penetrate an inductance core side by side to form an output inductor, resistance values of the current sharing portions of the first connecting piece and the second connecting piece being equal or a resistance difference value therebetween being within a preset range. The present disclosure can quickly, accurately and conveniently improve the efficiency and the heat dissipation of the synchronous rectifier module, and achieve a better current sharing effect of the connecting pieces by adjusting the resistance value numerical range of the two connecting pieces.

A method and circuit controls a synchronous rectifier. The synchronous rectifier is turned OFF by driving a gate of the synchronous rectifier to one or more first voltages that are non-zero. One or more values of the drain or the source of the synchronous rectifier are monitored. The gate of the synchronous rectifier is driven to a second voltage that is less than the one or more first voltages whenever the one or more values of the drain or the source of the synchronous rectifier pass above or below one or more threshold values.

The invention discloses a topological structure of a single-phase isolation type integrated vehicle-mounted charging system without an electrolytic capacitor and a control method of the topological structure, the system multiplexes a driving motor stator winding on the basis of an open winding driving system of an electric vehicle, and when the system is switched from a driving operation mode to a charging operation mode, the driving motor stator winding is switched to the charging operation mode. An open winding permanent magnet motor driving system is reconstructed into an isolated AC / DC converter without an electrolytic capacitor through a change-over switch, the isolated AC / DC converter comprises a synchronous rectifier, a dual-active-bridge converter and an active filtering device, phase shifting is controlled through matching of transmission power and network side input power, power factor correction is achieved, and power factor correction is achieved through winding inductive current control. According to the vehicle-mounted power battery integrated vehicle-mounted charging system, the inherent secondary power pulsation is filtered out to realize active filtering, and the torque pulsation suppression of a multiplexing motor winding is realized through a magnetic flux balance method, so that the vehicle-mounted power battery integrated vehicle-mounted charging system with an isolation charging characteristic is obtained, the integrated design of a driving charging function is realized, and the reliability and the safety of the integrated charging system are improved.

A magnetic inductive resonance charging circuit includes a resonant network having an inductive secondary coil that converts a magnetic field received from an inductive primary coil into an alternating current (AC) signal and a synchronous rectifier that rectifies the AC signal to generate a direct current (DC) signal for application to a load. The synchronous rectifier includes a variety of configurations for shunting the AC waveform of an AC current source in the event of a fault. For example, a rectifier controller may hold a pair of normally open switches of the rectifier off and a pair of normally closed switches of the rectifier on to shunt the AC current source when an over-voltage, over-current fault condition or an over-temperature fault condition is detected. Configurations are provided for grounding the capacitive electromagnetic interference produced in the chassis of an electric vehicle when the resonant network is unbalanced.

A control circuit and method for an isolated switching-mode converter are disclosed. In the control circuit, in preparation for turning on a primary transistor switch in a primary-side circuit, preferably, a secondary-side controller transmits an inquiry signal to a primary-side controller, and the primary-side controller transmits, after confirming that it has been prepared, a feedback signal to the secondary-side controller to allow the secondary-side controller to confirm that the primary transistor switch has been turned off. After that, the primary-side controller turns on the primary transistor. In other words, in the control circuit and method of the present invention, in preparation for turning on the primary transistor switch, information exchange is conducted between the primary and secondary sides to make sure that the primary transistor switch is turned on after the synchronous rectifier transistor is turned off.

The invention discloses a bidirectional six-switch buck-boost topology circuit and a control method thereof, and belongs to the technical field of power electronics. According to the scheme, two switch tubes and one inductor are additionally arranged on the basis of a four-switch buck-boost circuit, and an input negative electrode and an output negative electrode are separated through the additionally arranged switch tubes and inductor, so that the problem that when different input source outputs are connected in parallel, a negative bus is directly connected to form circulating current is effectively solved; a loop does not need to judge an input and output voltage relation, the duty ratio of a power switch tube is automatically adjusted directly according to the set voltage, current and energy transfer direction, and the boost-buck state of the topology is determined according to the calculation result of the duty ratio, so that the control on the energy transfer direction is realized; the on / off of the synchronous rectifier tube is determined by the magnitude of the output current. By adopting the scheme of the embodiment of the invention, the circulating current problem caused by multi-path input difference can be solved, the topology control difficulty is reduced, and the control error-tolerant rate is improved.

The invention provides a modulation mode switching synchronous rectification soft switching buck type constant voltage power supply which comprises an input filter circuit, a power inductor L1, an output filter circuit, a main switch tube Q1, a synchronous rectification tube Q2 and a control circuit. The left end of the power inductor L1 is connected to the source electrode of the main switch tube Q1 and the drain electrode of the synchronous rectifier tube Q2, the right end of the power inductor L1 is connected to the positive electrode of the output capacitor, the drain electrode of the main switch tube Q1 is connected to the positive electrode of the input capacitor, and the source electrode of the synchronous rectifier tube Q2 is connected to a reference ground through a power inductor current sampling resistor RS1; and the control circuit respectively controls the on-off states of the main switch tube Q1 and the synchronous rectifier tube Q2 so as to realize zero-voltage conduction of the synchronous rectifier tube Q2. Through the characteristics of different modulation modes, light-load and heavy-load modulation mode switching and synchronous rectifier tube soft switching are realized, and the loss of the switching power supply under different conditions is reduced.

The invention relates to an LLC resonant soft switching converter based on self-detection synchronous rectification and a control method thereof. The converter comprises an LLC resonance circuit, a secondary transformer with a center tap, a self-detection synchronous rectification circuit, an input filter circuit, an output filter circuit, an LLC resonance control circuit, a primary PFM drive circuit, an optocoupler isolation circuit, an output voltage sampling circuit and an operational amplifier compensation circuit. Switching tubes S1 and S2 in the primary PFM drive circuit adopt high-voltage MOS tubes, secondary synchronous rectifier tubes S3 and S4 adopt low-voltage MOS tubes, output voltage feedback control and secondary synchronous rectifier tube self-detection drive control are adopted, and the resonant soft switching converter with the 240V-300V input voltage range, the constant output of 28V / 300W and the full-load efficiency of 92% is realized. According to the invention, zero-voltage switching-on of the primary switch tube, zero-current switching-off of the secondary synchronous rectifier tube and accurate synchronous rectification control are realized, the loss of the rectifier circuit is reduced, the efficiency of the converter is improved, and the electromagnetic compatibility characteristic of the converter is optimized.

A power converter incorporating a synchronous rectifier implements adaptive turn-off voltage control for fast turn-off of the synchronous rectifier in the continuous conduction mode. In some embodiments, the synchronous rectifier turn off detection threshold is adaptively changed as a function of the detected operation mode of the power converter. In response to detecting the power converter being operated in the continuous conduction mode, the synchronous rectifier turn off detection threshold is set to a voltage value farther away from zero volt as compared to the nominal turn off detection threshold. In this manner, the synchronous rectifier can be turned off earlier while in the continuous conduction mode. When the synchronous rectifier can be turned off quickly, large reverse current or negative current as well as large drain voltage spike at the synchronous rectifier can be avoided. The reliability of the synchronous rectifier and the power converter is improved.

The utility model provides a flyback converter and a primary state detection circuit thereof, in a detection interval, when a drain terminal voltage of a synchronous rectifier is greater than an output voltage, integration is carried out from zero based on a difference value between the drain terminal voltage and the output voltage to obtain a first volt-second integral; the volt-second integral judgment module compares the first volt-second integral with a preset integral threshold value and outputs a first judgment signal; the pulse signal generation module generates a first short pulse signal and a second short pulse signal at the starting moment and the ending moment of a detection interval respectively; the pulse counting module counts pulses based on the first judgment signal, the first short pulse signal and the second short pulse signal and outputs a first count value; the synchronous rectifier driving control module judges that the flyback converter primary stage is in a fault state based on the first count value; and when the flyback converter is in the primary fault state, stopping driving the synchronous rectifier. By means of the arrangement, when the primary stage breaks down, the common phenomenon of the primary stage and the secondary stage can be avoided.

The invention provides a control method for suppressing light-load turn-off stress of a synchronous rectifier tube. The control method comprises the following steps: determining a control module setting end level based on a preset high-level threshold voltage and a control module setting end voltage; receiving a power supply fault signal, and determining a control module data end level based on the power supply fault signal; receiving a clock signal, and determining the driving end level of the control module based on the clock signal; determining a control module output end level based on the control module data end level, the control module driving end level and the control module setting end level so as to generate a PWM closing signal based on the control module output end level; and controlling the main control module to close PWM output at a preset safety moment based on the PWM closing signal, thereby realizing suppression of the turn-off stress of the synchronous rectifier tube. According to the control method and circuit for suppressing the light-load turn-off stress of the synchronous rectifier tube, the power supply fault signal and the clock signal are combined to control the main control module to turn off PWM output at the safe moment, and the stress problem of the synchronous rectifier tube is avoided.

The invention discloses a flyback converter control circuit, a control method and a switching power supply, the control circuit comprises a primary side control circuit and a secondary side control circuit, and the secondary side control circuit comprises a first control driving unit which sends a first conduction signal to a synchronous rectifier tube according to a compensation signal so as to conduct the synchronous rectifier tube, so that a negative current is generated on a main power tube, and the negative current is generated on the main power tube; the compensation signal represents an error between an output feedback signal and a reference signal of the flyback converter; the volt-second product obtaining unit is used for calculating the volt-second product of the voltage at the two ends of the secondary winding within the first time after the first conduction signal is generated; and the volt-second judging unit is used for comparing the volt-second product with a volt-second product threshold value and judging the communication state of the primary side control circuit and the secondary side control circuit. And when the volt-second product is greater than the volt-second product threshold value, the handshake of the primary side control circuit and the secondary side control circuit is successful. Through the detection process, handshaking of the primary side and the secondary side is achieved, accurate control of the secondary side over the primary side is achieved, no extra isolator is needed, and the circuit cost and loss are reduced.

The invention discloses a double-half-bridge direct-current converter integrated structure. Comprising an input direct-current power supply Vin, a first switch tube S1, a second switch tube S2, a third switch tube S3, a fourth switch tube S4, a first resonance unit circuit, a second resonance unit circuit, a transformer T, a first synchronous rectifier tube SR1, a second synchronous rectifier tube SR2, a third synchronous rectifier tube SR3, a fourth synchronous rectifier tube SR4, a first output filter capacitor Co1 and a second output filter capacitor Co2, the transformer T comprises a first primary winding PT1, a second primary winding PT2, a first secondary winding ST1, a second secondary winding ST2, a third secondary winding ST3 and a fourth secondary winding ST4. Full-period work of the transformer winding is achieved, the winding utilization rate is high, the shortest alternating current path, high efficiency and high power density of the winding are achieved, winding loss and the occupied area are effectively reduced, control is easy, reliability is high, and implementation is easy.

The invention provides a voltage-limiting conduction synchronous rectification control method and a control chip, a synchronous detection comparison circuit detects drain-source voltage of a synchronous rectification switch tube, and the synchronous rectification switch tube is fully conducted when the drain-source voltage is smaller than a turn-on threshold value; and when the drain-source voltage is greater than the turn-off threshold value, the synchronous rectification switch tube is turned off. The voltage-limiting conduction trigger circuit detects drain-source voltage after the synchronous rectification switch tube is fully conducted, and when the voltage-limiting conduction condition is met, a voltage-limiting conduction effective signal is output to the logic circuit and the voltage-limiting conduction control circuit to trigger voltage-limiting conduction control. According to the invention, by detecting the drain-source voltage value of the synchronous rectification switch tube, the synchronous rectification switch tube is controlled to be fully turned on, and turn-on and turn-off are limited. The circuit can be compatible with a DCM mode and a CCM mode at the same time, and in the DCM mode, the synchronous rectification switch tube is turned off only when the current is very small; and in the CCM mode, the turn-off delay is very fast.

The invention belongs to the technical field of planar transformers, and relates to a fractional-turn planar transformer of a matrix type integrated structure and a converter. Comprising M magnetic cores and a PCB (printed circuit board), and each magnetic core is provided with a plurality of layers of primary windings and N sections of secondary windings; a circuit structure is arranged between the secondary winding on the first surface and the secondary winding on the second surface, and a source electrode of a synchronous rectifier tube in the circuit structure is connected with a grounding end of an output capacitor; positive potential ends, back to two output capacitors in the circuit structure, on the first surface and the second surface are connected; according to the planar transformer, the advantages of the fractional turn scheme and the matrix scheme of the existing planar transformer are combined, the defects of the fractional turn scheme and the matrix scheme are suppressed, and the requirements of the market for the high-transformation-ratio transformer on the higher server power supply bus voltage are met.

The invention discloses a flyback converter control circuit, a control method and a switching power supply, the flyback converter comprises a primary side main power tube and a secondary side synchronous rectifier tube, the flyback converter control circuit comprises a primary side control circuit, a secondary side control circuit and a secondary side control circuit, the primary side control circuit is used for controlling the primary side main power tube to be switched on and switched off periodically in a starting stage after power-on so as to enable the secondary side to be powered on, and the secondary side control circuit is used for controlling the secondary side synchronous rectifier tube to be powered on; and the secondary side control circuit enables the synchronous rectifier tube to follow current after the main power tube is turned off, and sends a zero-voltage starting control signal to conduct the synchronous rectifier tube after the secondary side is electrified, so that negative current is generated on the main power tube. The primary side control circuit controls the main power tube to maintain the turn-off state within a first time period after the follow current of the synchronous rectifier tube is detected to be finished, and the time period when the secondary side control circuit generates the zero-voltage turn-on control signal is within a second time period after the actual follow current of the synchronous rectifier tube is finished. The end time of the second time is earlier than or equal to the end time of the first time. The primary side and the secondary side are conducted in a time-sharing mode, and common connection of the primary side and the secondary side is avoided in the starting stage.

A battery pack charger having housing including a battery pack interface for removably receiving a battery pack and a power input. The battery pack charger including a hybrid flyback converter having a primary side including a DC-DC half-bridge and a secondary side including a synchronous rectifier. The hybrid flyback converter is electrically connected between the power input and the battery pack interface and is configured to provide charging power from the power input to the battery pack interface.

The invention provides a processing method and device of a synchronous rectification driving circuit and a resonant converter, and relates to a synchronous rectification driving technology, and the method comprises the steps: obtaining a primary side driving signal for a primary side switching tube in a primary side circuit through a main control circuit; and acquiring a driving protection signal corresponding to the corresponding synchronous rectifier tube based on the primary side driving signal for one path of primary side switch tube. And a self-driven driving signal corresponding to the corresponding synchronous rectification tube is obtained through the synchronous rectification driving circuit. Generating a synchronous rectifier tube driving signal according to the driving protection signal and the self-driving signal; and controlling the on and off of the corresponding synchronous rectifier tube according to the synchronous rectifier tube driving signal. According to the method, the synchronous rectifier tube is turned off in time, direct connection of the upper and lower synchronous rectifier tubes of the synchronous rectifier circuit and short circuit of the secondary side of the transformer caused by drive delay turn-off are avoided, and the problem of drive direct connection of the upper and lower tubes of the synchronous rectifier tube is solved.

The invention provides a flyback converter and a control circuit and a control method thereof, and the control circuit comprises a primary side control circuit which is used for controlling the on and off of a main power tube; the secondary side control circuit is used for controlling the switch-on and switch-off of the synchronous rectifier tube so as to control the first time of switch-on of the synchronous rectifier tube before the excitation current of the flyback converter reaches a zero crossing point for the first time and the second time of switch-on of the synchronous rectifier tube after zero crossing of the excitation current, and the secondary side control circuit determines second time according to a preset volt-second reference and the output voltage of the flyback converter. According to the invention, the extra turn-on pulse width of the synchronous rectifier tube is set in a volt-second integration mode, the magnitude of the negative excitation current can be controlled, negative current sampling during zero voltage turn-on is facilitated, and meanwhile, zero voltage turn-on in a full input voltage range can be realized to the greatest extent, so that the system efficiency is improved.

A control circuit of an isolated power supply, an isolated power supply and a control method thereof are disclosed. The control circuit includes a primary original signal generator generating a primary original turn-on signal based on a voltage feedback signal of an output voltage of the isolated power supply, and a secondary control signal generator generating a secondary control signal based on a secondary voltage signal and the primary original turn-on signal. In a current switching period, only when an expected turn-on instant for a primary main transistor switch is earlier than an expected turn-on instant for a secondary synchronous rectifier, will the secondary control signal provide an indication to turn on the secondary synchronous rectifier.

The invention provides an isolated switching power supply circuit with a dynamic response control function, a secondary side control circuit of the isolated switching power supply circuit and a power supply control method. The secondary side control circuit comprises a rectifier tube control signal generation circuit which provides a rectifier tube control signal for controlling the synchronous connection and disconnection of a synchronous rectifier tube; the input end of the power supply circuit is coupled with the second end of the synchronous rectifier tube, the output end of the power supply circuit is coupled with the power supply end of the secondary side control circuit and used for providing power supply voltage for the secondary side control circuit, and in the period when the synchronous rectifier tube stops follow current, the power supply circuit supplies power in a first current state in a first time period, and the power supply circuit supplies power in a second current state in a second time period. In the second time period, the power supply circuit supplies power in a second current state when supplying power, and the maximum value of the power supply current in the first current state is larger than the maximum value of the power supply current in the second current state. According to the invention, while power supply through the secondary side synchronous rectifier tube is fully satisfied, false triggering of dynamic response control is avoided, and improper output voltage increase and device damage can be avoided.

This disclosure presents an embodiment of a power supply device for a submarine data center. One specific embodiment of the power supply device includes a pre-stage voltage regulator / conversion component, a post-stage DC-DC converter component, and a combined protection circuit. The pre-stage voltage regulator / conversion component includes several parallel single-group voltage regulator branches, each branch connected in series with a varistor and a color-coded resistor. A thin-film capacitor is connected in parallel to the output terminal of the pre-stage voltage regulator / conversion component. The post-stage DC-DC converter component, electrically connected to the pre-stage voltage regulator / conversion component, includes at least two sets of full-bridge DC synchronous rectifier circuits. The combined protection circuit includes a pre-stage combined protection circuit, a post-stage active voltage clamping circuit connected in parallel to the output side of the post-stage DC-DC converter component, and a rectifier diode bridge connected between the constant current input port and the pre-stage voltage regulator / conversion component. The pre-stage combined protection circuit is connected in series to the input side of the rectifier diode bridge. By connecting multiple voltage regulator branches in parallel and combining them with the combined protection circuit, ripple is reduced. This embodiment can improve the power supply stability of the power supply device.

A power converter can include: M transformer units, each including primary and secondary windings; M bridge arms, each being is coupled between two input terminals of the power converter to receive a DC input voltage, and each bridge arm comprises a high-side switch, a low-side switch, and a synchronous rectifier coupled in series; where a first terminal of each of the primary windings is coupled to a common node between the high-side switch and the low-side switch in one of the M bridge arms, and a second terminal of each primary winding is coupled together; and where one terminal of each of the secondary windings is coupled to a common node between the low-side switch and the synchronous rectifier in one of the M bridge arms, and the other terminal of each of the secondary windings is coupled to a first output terminal of the power converter.