Abstract: An example controller for a primary side control power converter includes a feedback circuit, a driver circuit, and an adjustable voltage reference circuit. The feedback circuit compares a feedback signal representative of a bias winding voltage of the power converter with a voltage reference. The driver circuit outputs a switching signal having a switching period to control a switch to regulate an output of the power converter in response to the feedback signal and enables or disables a switching period based on the output of the feedback circuit. The adjustable voltage reference circuit adjusts the voltage reference by a first amount in response to a first number of disabled switching periods indicating a first load condition at the output of the power converter and by a second amount in response to a second number of disabled switching periods indicating a second load condition at the output of the power converter.

Abstract: A high-frequency DC to DC converter comprising n transient converter circuits (1, 2 . . . n) operating in parallel. The converter has constant transfer characteristics, and the transient converter circuits are operated phase-shifted by 360°/n and with interleaved duty cycles, which results in a continuous energy transfer through the circuit. The circuit is also soft-switched, with very low switching losses. In particular, the active semiconductors only switch off a relatively small magnetization current, during a recovery phase which can last as long as (n?1)/n of the switching phase period.

Abstract: Disclosed is a circuit arrangement for determining a temporal change of an output voltage of a half-bridge circuit during a dead time. In one embodiment, the circuit arrangement includes a first input for applying the output voltage. A capacitive network includes a first and a second circuit node capacitively coupled to the input, and having a terminal for a reference potential. A recharging circuit during the switched-on phase of one of a first and second switching elements, adjusts electrical potentials of the first and second nodes, the electrical potentials each being different from the reference potential. A comparator arrangement, during the dead time, determines a time difference between such times at which the electrical potentials at the first and second node each assume a given potential value, the time difference being a measure for the change with time of the output voltage.

Abstract: This disclosure relates to a switching power supply with regulated voltage suppression to reduce transformer audio noise. A switched mode power supply (SMPS) may supply power at different levels according to output loads. A switching frequency of the SMPS may be adjusted according to the output load. The switching may be subject to a ringing suppression time, a maximum on time, and a maximum switching period. By controlling the switching frequency subject to these quantities, the audible noise of an SMPS may be reduced or eliminated.

Abstract: In a direct-current power supply device that includes a smoothing capacitor C1, which performs a DC/DC converter operation, a transformer T1, a switching element Q1, a diode D2, a smoothing capacitor C2, a reactor L1, which performs a PFC operation, a fast recovery diode D1 and a switching element Q1, when compared with the case of a rated load, the voltage of the smoothing capacitor C1 of a PFC circuit rises at a time when a load is light. Therefore, the following has been required: a capacitor having a sufficient withstanding voltage rating, or an operation of connecting a plurality of capacitors in series or any other operation to secure a voltage-withstanding capability.

Abstract: A system and method for extracting power from a power source having a high internal resistance are presented. A capacitor is connected to the power source. A switch is configured to selectively connect and disconnect the capacitor from a load. A processor is configured to monitor an energy flow from the power source into the capacitor and an amount of energy in the capacitor. When the energy flow from the power source into the capacitor falls below a first threshold, the processor is configured to close the switch to dissipate energy from the capacitor to the load. When the energy in the capacitor falls below a second threshold, the processor is configured to open the switch to disconnect the capacitor from the load.

Abstract: An example power supply includes a first power converter, a second power converter, and a shared clamp reset circuit. The first power converter is adapted to convert an input to a first voltage output and includes a first diode and a first transformer having a first primary winding. The second power converter is adapted to convert the input to a second voltage output and includes a second diode and a second transformer having a second primary winding. The shared clamp reset circuit is included in the first power converter and is coupled to the cathode of the first diode. The shared clamp reset circuit also includes a clamp connection that is coupled to the cathode of the second diode. The shared clamp reset circuit is adapted to manage leakage inductance energy within the first transformer and within the second transformer.

Abstract: Methods, circuit designs, systems, and devices for the conversion of high voltage alternating current (AC) to low voltage, high current direct current (DC) are described. An exemplary apparatus includes a rectifier for receiving a high voltage AC line power input and for outputting a full wave, high voltage DC, a gating component coupled to the rectifier for receiving the high voltage DC output by the rectifier, wherein the gating component is configured to gate the high voltage DC by turning on at a zero crossing level and turning off when the high voltage DC exceeds a preset voltage threshold and wherein the output of the gating component is an intermediate voltage DC capped by the preset voltage threshold, and a DC-DC converter coupled to the gating component for receiving the intermediate voltage DC output by the gating component, wherein the DC-DC converter is configured to step down and smooth out the intermediate voltage DC to a desired high current, low voltage DC output.

Abstract: A voltage converter (10) comprises an input (11) for receiving an input voltage (VIN), a first output (12) for providing a first output voltage (VPOS) and a second output (13) for providing a second output voltage (VNEG). The first output voltage (VPOS) and the second output voltage (VNEG) have opposite polarities. A switching arrangement (14) of the voltage converter (10) is designed to provide energy to an inductor (15) in a charging phase (A) of operation and to provide energy from the inductor (15) to the first output (12) and, via a flying capacitor (16), to the second output (13) in a discharging phase of operation. The first duration (t1) of the charging phase (A) of operation is controlled such that the difference between a first predetermined value and the sum of the absolute value of the first output voltage (VPOS) and of the second output voltage (VNEG) is minimized.

Abstract: A switching converter circuit includes bipolar devices in a Darlington configuration as a main switching element. Current drive is provided to the first base terminal to turn on the Darlington bipolar device. Base relaxation circuits to both the first and inner base terminals turn off the Darlington bipolar device.

Abstract: Provided is a synchronous rectifier circuit which, even if a synchronous rectification element having a low on-resistance is used, can perform a synchronous rectifying operation without being influenced by the inductance component. It is a synchronous rectifier circuit having a synchronous rectification element QSR1 and a synchronous rectification control circuit IC1 for turning on/off the synchronous rectification element QSR1 in accordance with the current iSR flowing through the synchronous rectification element QSR1, including a current detection circuit for detecting the current iSR flowing through the synchronous rectification element QSR1 during an on-period of the synchronous rectification element QSR1 as a synchronized voltage waveform, the synchronous rectification control circuit IC1 being configured so as to turn off the synchronous rectification element QSR1 on the basis of the voltage waveform detected by the current detection circuit 1a.

Abstract: In one embodiment, a power supply controller is configured to adjust a peak value of a primary current through a power switch responsively to a difference between a demagnetization time and a discharge time of the parasitic leakage inductance of a transformer.

Abstract: Disclosed is a DC-DC converter. The DC-DC converter includes a power input unit to which power is applied, a first module comprising a first transformer and a second transformer to output a first output power transformed according to operations of a first switch and a second switch connected with the first transformer and the second transformer by using the applied power, a second module comprising a third transformer and a fourth transformer to output a second output power transformed according to operations of a third switch and a fourth switch connected with the third transformer and the fourth transformer by using the applied power, an output unit to output a sum of the first output power and the second output power, and a controller to control an interleaving operations between the first module and the second module.

Abstract: A power source capable of supplying power to operate electronics of a system is disclosed. In one example, the power source takes advantage of an electrical potential difference between primary and secondary grounds. The power source can reduce system cost and power consumption.

Abstract: A DC-DC converter includes a power conversion circuit for converting a DC input voltage to a DC output voltage; and an active clamp circuit for soft switching a first active switching element of the power conversion circuit and recovering leakage inductance energy of a main transformer of the power conversion circuit, As such, the present disclosure provides a DC-DC converter that reduces the switching loss of the switching elements and effectively recovers the leakage inductance energy, thus increasing the conversion efficiency of the converter.

Abstract: There is disclosed a power supply stage, comprising: generating means for generating a power supply voltage from a high efficiency variable voltage supply in dependence on a reference signal; adjusting means for receiving the generated power supply voltage, and adapted to provide an adjusted selected power supply voltage tracking the reference signal in dependence thereon.

Abstract: Disclosed are AC-DC voltage converter circuits and methods for low standby power consumption. In one embodiment, a method can include: (i) detecting operating states of an input power supply, where the input power supply is received by a safety capacitor and provided to a switching power supply circuit after being rectified and filtered; (ii) removing a phantom load when the input power supply operates in a normal operating state; (iii) loading the phantom load when the input power supply operates in an under voltage lock out state; and (iv) when the input power supply operates in the under voltage lock out state, using energy stored in the safety capacitor to supply power to a load of the switching power supply circuit and the phantom load, and disabling a power stage circuit until a voltage of the safety capacitor is reduced to less than a safety threshold value.

Abstract: In accordance with an embodiment, a switch controller for a switched-mode power supply includes an oscillator, an advance timing generator, and a dead zone generator. The advance timing generator generates an advance timing output pulse having a first pulse width that is asserted when the oscillator reaches a first phase. The dead zone generator produces a dead zone output having a second pulse width when the advance timing output pulse is de-asserted. This dead zone output pulse is coupled to a freeze input of the oscillator that freezes the phase accumulation of the oscillator when asserted. The controller also has a primary switch logic circuit that produces primary switch drive signals having a dead zone coincident with the dead zone output, and a secondary switch logic circuit that generates a secondary switch drive signal that is de-asserted when the advance timing output pulse becomes asserted.

Abstract: An electronic system includes a controller that actively controls a rate of charging and discharging of an energy storage capacitor to maintain compatibility with a dimmer. The controller actively controls charging of a capacitor circuit in a switching power converter to a first voltage level across the capacitor circuit. The controller further allows the capacitor to discharge to obtain a second voltage level across the capacitor circuit. The second voltage level is sufficient to draw a current through a phase-cut dimmer to prevent the dimmer from prematurely resetting. The first voltage is sufficient to allow the capacitor to discharge to the second voltage level during each cycle of the line voltage.

Abstract: A switching circuit for use in a power converter includes a first active switch coupled between a first terminal of an input of the power converter and a first terminal of a primary winding of a transformer. A second active switch is coupled between a second terminal of the input and a second terminal of the primary winding. An output capacitance of the first active switch is greater than an output capacitance of the second active switch. A first passive switch is coupled between the second terminal of the primary winding and the first terminal of the input. A second passive switch is coupled between the second terminal of the input and the first terminal of the primary winding. A reverse recovery time of the first passive switch is greater than a reverse recovery time of the second passive switch.

Abstract: A system simplification can be achieved by reducing the number of sensors required to detect currents and voltages when an output current is estimated. A switching power supply device 6 includes a current transformer 12, a switching circuit 13, a rectifying circuit 15, a smoothing circuit 16, an input voltage detecting circuit 18, a control part 19, an output voltage detecting circuit 22 and a PWM signal generating part 30. The control part 19 calculates a duty rate and an average value of voltage of the secondary side voltage of the current transformer 12 detected by the input voltage detecting circuit 18 based on a waveform of the detected voltage. The control part 19 calculates an output current lo based on the calculated duty rate, the calculated average value of voltage and an output voltage Vo detected by the output voltage detecting circuit 22.

Abstract: A switching mode power supply (SMPS) includes a rectifying device configured for converting a periodically varying input AC (alternating current) voltage into a DC (direct current) voltage, and a transformer including a primary winding, a secondary winding, and an auxiliary winding. The primary winding is coupled to the rectifying device. An input capacitor is coupled to the rectifying device and the primary winding of the transformer. A first power switch is coupled to the input capacitor. A control circuit is coupled to the first power switch and is configured to control the first power switch based on a phase or amplitude of the input AC voltage. By controlling the charging and discharging of the input capacitor, power is provided to the primary winding during a longer portion of the AC input voltage cycle, allowing the rectifier device to have a larger conduction angle to increase a power factor (PF).

Abstract: An example control element for use in a power supply includes a high-voltage transistor and a control circuit to control switching of the high-voltage transistor. The high-voltage transistor includes a drain region, source region, tap region, drift region, and tap drift region, all of a first conductivity type. The transistor also includes a body region of a second conductivity type. An insulated gate is included in the transistor such that when the insulated gate is biased a channel is formed across the body region to form a conduction path between the source region and the drift region. A voltage at the tap region with respect to the source region is substantially constant and less than a voltage at the drain region with respect to the source region in response to the voltage at the drain region exceeding a pinch off voltage.

Abstract: This is an insulation-type power factor correction circuit including a resonance unit configured to accumulate energy of a surge occurring when the first switching element is turned off and to transmit a resonance current generated by resonating the first capacitor and the primary winding of the second transformer from the primary winding of the second transformer to the secondary winding, a rectifier unit configured to rectify a resonance current output from the resonance unit, a smoothing unit configured to regenerate power output from the rectifier unit to an output of the insulation-type power factor correction circuit, and a control unit configured to control a first switching element for each cycle.

Abstract: A power supply unit includes a switching power converter responsive to a control signal to switch a power switch thereof to provide an output voltage and an output current for a load. To reduce light-load or no-load power consumption of the power supply unit, the power supply unit repeats a process of stopping switching the power switch and recovering switching the power switch for a period of time once the output voltage decreases to be lower than a reference voltage.

Abstract: A power supply includes a forward converter having a first transformer coupled to an input of the power supply and to a first voltage output. The power supply also includes a separate flyback converter having a second transformer that is coupled to the input and to a second voltage output. A clamp reset circuit is coupled to the first transformer and to the second transformer. The clamp reset circuit includes a capacitor and a voltage limiting element. The voltage limiting element is coupled to prevent energy received at the capacitor from both the power converters from exceeding a threshold. The voltage limiting element limits a voltage on the capacitor.

Abstract: The present invention is to provide a power converter, which includes a half-bridge circuit parallel-connected to an input voltage and having two series-connected power switches, an LLC resonant circuit formed by a resonant inductor, magnetic inductance of a primary winding and a resonant capacitor, a current-circulating circuit parallel-connected to the half-bridge circuit and having two series-connected rectifiers, and a full-wave rectification circuit connected to a secondary winding for generating an output voltage across an output capacitor. The LLC resonant circuit is parallel-connected to one of the power switches, and the line between the two rectifiers is cross-connected to the line between the resonant inductor and the primary winding.

Abstract: A power system includes a plurality of DC/DC converters and a DC/AC inverter. The plurality of DC/DC converters having outputs electrically connected in parallel for supplying a DC voltage bus to an input of the DC/AC inverter. The plurality of DC/DC converters each include a maximum power point tracker (MPPT). Various DC/DC converters and DC/AC inverters suitable for use in this system and others are also disclosed.

Abstract: System and method for regulating an output voltage of a power conversion system. The system includes an error amplifier coupled to a capacitor. The error amplifier is configured to receive a reference voltage, a first voltage, and an adjustment current and to generate a compensation voltage with the capacitor. The first voltage is associated with a feedback voltage. Additionally, the system includes a current generator configured to receive the compensation voltage and generate the adjustment current and a first current, and a signal generator configured to receive the first current and a second current. The signal generator is further configured to receive a sensing voltage and to generate a modulation signal. Moreover, the system includes the gate driver directly or indirectly coupled to the signal generator and configured to generate a drive signal based on at least information associated with the modulation signal.

Abstract: A switching power supply device that can reduce power supply noise includes a switching power supply device main body that switches a semiconductor switching element at a power supply frequency fs, and supplies power to an electronic instrument such as an AM radio receiver. The switching power supply device detects an AM radio reception frequency fc and a power supply harmonic component that interferes with the AM radio reception frequency fc. Further, the switching power supply device determines, in a sideband of the AM radio reception frequency fc on a side that does not include the power supply harmonic component, a jitter width ?f for the power supply frequency fs, avoiding a bandwidth BW of the AM radio reception frequency fc, controlling the jitter of the power supply frequency fs in the jitter width ?f, and switching the semiconductor switching element at a frequency of [fs±?f/2].

Abstract: AC-DC converter is provided which comprises an auxiliary winding 8c in a transformer 8, a voltage detector 21 for detecting a voltage VN appearing on auxiliary winding 8c of transformer 8 by on-off operation of a main switching element 9 in a DC-DC converter 10 to produce an output signal VCP1 when voltage VN on auxiliary winding 8c has a negative polarity, a waveform shaper 23 for generating chopping signals VRC from output signal VCP1 of voltage detector 21, and a PWM circuit 27 for comparing output voltage VRC from waveform shaper 23 and output voltage VCH from a boosting chopper 3 to supply drive signals VG1 to step-up switching element 5 in boosting chopper 3 when output voltage VRC from waveform shaper 23 exceeds output voltage VCH from boosting chopper 3. While controlling fluctuation in output voltage from boosting chopper with respect to fluctuation in AC input voltage, the converter can improve input power factor relative to AC voltage and also reduce consumption power during light load period.

Abstract: Transformer flux is monitored to determine if an onset of flux saturation is detected. If flux saturation is not detected, the transformer drive signal is received to a switch that maintains the polarity of the transformer flux. If flux saturation is detected, the transformer drive signal is received by a switch that reverses the polarity of the transformer signal and the transformer flux. This reversal of flux polarity can occur multiple times, during the carrier cycle of the drive signal, without compromising the dynamics of the transformer main control loop or requiring the drive signal to be regenerated.

Abstract: Apparatus for cancelling electromagnetic interference (EMI) during power conversion. In one embodiment, the apparatus comprises a power converter for converting a DC input to a DC output, wherein the power converter comprises a transformer having a primary winding and a secondary winding, the secondary winding coupled to a diode such that a plurality of secondary winding voltages cause a balanced current flow through a plurality of parasitic capacitances.

Abstract: A power supply device includes a transformer; a series circuit of two bidirectional switching elements connected between terminals of the commercial power supply and having a rectification function and a switching function; an LC resonant circuit connected between a primary coil of the transformer and both ends of one of the bidirectional switching elements; a rectifying element connected to a secondary coil of the transformer; and a control circuit for inputting a gate driving signal to the bidirectional switching elements. The power supply device performs synchronous rectification from the bidirectional switching elements.

Abstract: Methods, circuit designs, systems, and devices for the conversion of high voltage alternating current (AC) to low voltage, high current direct current (DC) are described. An exemplary apparatus includes a rectifier for receiving a high voltage AC line power input and for outputting a full wave, high voltage DC, a gating component coupled to the rectifier for receiving the high voltage DC output by the rectifier, wherein the gating component is configured to gate the high voltage DC by turning on at a zero crossing level and turning off when the high voltage DC exceeds a preset voltage threshold and wherein the output of the gating component is an intermediate voltage DC capped by the preset voltage threshold, and a DC-DC converter coupled to the gating component for receiving the intermediate voltage DC output by the gating component, wherein the DC-DC converter is configured to step down and smooth out the intermediate voltage DC to a desired high current, low voltage DC output.

Abstract: There are provided a power switching driving apparatus able to reduce a circuit area and increase a driving speed, and a power factor correction device and a power supply device having the same. The power switching driving apparatus includes: a first driving unit providing a switching signal in response to a control signal from the outside; a second driving unit including first and second NMOS FETs cascode-connected between an operational power source terminal supplying pre-set operation power and a ground, and performing switching complimentarily in response to the switching signal to provide a switching control signal controlling power switching; a current supply unit supplying a current for driving the second driving unit; and a voltage maintaining unit maintaining a voltage for driving the second driving unit.

Abstract: The present invention relates to a trigger circuit for a switch in a switching power supply, especially in a primary-side, triggered switching power supply. The trigger circuit here comprises a feedback signal terminal for detecting an auxiliary voltage induced on a primary-side auxiliary winding of a transformer of the switching power supply, a supply voltage terminal for supplying the trigger circuit with a supply voltage, and a ground terminal for connecting the trigger circuit to a ground potential, wherein the feedback signal terminal is formed by the supply voltage terminal and the auxiliary voltage is superimposed on the supply voltage. Alternatively, the voltage of the auxiliary winding could be superimposed on the voltage on an additional pin that is used for detecting the primary peak current.

Abstract: An embodiment of the invention relates to an LLC power converter including a controller configured to regulate an output characteristic of the power converter by controlling a power converter switching frequency. In a first mode of operation, the controller turns off a secondary-side power switch earlier than a turn-off time of a primary-side power switch by a time difference that is controlled by a resistor coupled to an external circuit node. In a second mode of operation, the controller turns on a secondary-side power switch at substantially the same time as the primary-side power switch, and turns off the secondary-side power switch after a maximum on time that is a nonlinear function of a load current of the power converter. The nonlinear function is a substantially constant function of the load current for a value of the load current higher than a threshold value.

Abstract: A power supply, which outputs a plurality of voltages in order to improve the cross regulation between output voltages and at the same time reduce the amount of electric power consumed, and an image forming device having the same are disclosed. The power supply includes a power converter, which generates a first output power source and a second output power source in response to an external power supply and a power control signal, respectively; a power output part, which includes output parts to rectify and smooth each of the first and second output power sources; a first output controller, which receives the first output power source feedback from the power output part to generate the power control signal; and a second output controller, which receives the second output power source feedback from the power output part to control to operate the power output part in stable mode.

Abstract: Methods, circuit designs, systems, and devices for the conversion of high voltage alternating current (AC) to low voltage, high current direct current (DC) are described. An exemplary apparatus includes a rectifier for receiving a high voltage AC line power input and for outputting a full wave, high voltage DC, a gating component coupled to the rectifier for receiving the high voltage DC output by the rectifier, wherein the gating component is configured to gate the high voltage DC by turning on at a zero crossing level and turning off when the high voltage DC exceeds a preset voltage threshold and wherein the output of the gating component is an intermediate voltage DC capped by the preset voltage threshold, and a DC-DC converter coupled to the gating component for receiving the intermediate voltage DC output by the gating component, wherein the DC-DC converter is configured to step down and smooth out the intermediate voltage DC to a desired high current, low voltage DC output.

Abstract: A switching circuit for use in a power supply includes a first active switch coupled to a first terminal of a primary winding of a transformer. A second active switch is coupled to a second terminal of the primary winding of the transformer. An output capacitance of the first active switch is greater than an output capacitance of the second active switch. A first passive switch is coupled to the second active switch and to the second terminal of the primary winding. A second passive switch is coupled to the first active switch and to the first terminal of the primary winding. A reverse recovery time of the first passive switch is greater than a reverse recovery time of the second passive switch. A recovery circuit is coupled to receive a current from the first passive switch.

Abstract: Consistent with an example embodiment, a circuit comprises a power factor correction stage having a DC input, a ground input, a DC output and a ground output. The circuit further includes a capacitor; a diode; and a discharge circuit. A first terminal of the diode is connected to an input of the power factor correction stage, a second terminal of the diode is connected to the first plate of the capacitor; and the second plate of the capacitor is connected to the other input of the PFC stage. The discharge circuit is connected to the capacitor and is configured to discharge the capacitor such that it contributes to the output of the PFC stage when the level of a signal at the input of the PFC stage falls below a threshold value.

Abstract: An AC-DC converter is disclosed. The AC-DC converter includes an OFF-time clamping circuit. The OFF time clamping circuit outputs a triggering signal when a main switch circuit of the AC-DC converter is switched from ON state to OFF state. When an input AC voltage is too small, and a terminal voltage at a first current-conducting terminal of the main switch circuit of the AC-DC converter is lower than a specific voltage such that a switching control circuit can not turn on the main switch circuit again, the switching control circuit can still turn on the main switch circuit again by the triggering signal. Therefore, the OFF time of the main switch circuit is clamped. The switching control circuit can control the switching operation of the main switch circuit.

Abstract: To provide an electrical junction box that can maintain a stable assembly condition between a box main body and a cover member, even if locking mechanisms are not provided on a whole periphery of the electrical junction box. An electrical junction box includes a box main body and a cover member. One of the box main body and the cover member is provided on at least a single of side portions of the one peripheral wall with a locking mechanism. An elastic rib that protrudes from an inner peripheral surface of the one peripheral wall at one of the side portions is pressed onto a fitting projection piece. A side portion is provided with a support wall that is opposed to and spaced apart from the inner peripheral surface. The fitting projection piece is held in a space between the inner peripheral surface and the support wall.

Abstract: An integrated circuit (IC) forming a pulse-width modulator controls the switching operation of an output stage of a switching power supply. A snubber capacitor that is coupled to a primary winding of a transformer of the output stage is used for producing a capacitive coupled charging current. The capacitive coupled charging current is coupled to a filter or charge storage second capacitor for producing in the second capacitor a first portion of a second power supply voltage. During a portion of a switching cycle of the output stage, the snubber capacitor is coupled to an inductor to form a resonant circuit. The resonant circuit produces in the second capacitor a second portion of the second power supply voltage for energizing the IC. The second power supply voltage is used for energizing the IC.

Abstract: A power supply includes a first power converter having a first transformer coupled to an input of the power supply and to a first output of the power supply. A clamp reset circuit is coupled to the first transformer. The clamp reset circuit includes a capacitor coupled to the first power converter and a Zener diode coupled to the capacitor. A second power converter is coupled to the clamp reset circuit. The second power converter includes a second transformer coupled to the clamp circuit and to a second output of the power supply. The capacitor is coupled to store energy received from the first power converter and the second power converter. The Zener diode is coupled to prevent the energy received from the first power converter and the second power converter from exceeding a threshold. The Zener diode limits voltage on the capacitor.

Abstract: An example power supply includes a first power converter, a second power converter, and a shared clamp reset circuit. The first power converter is adapted to convert an input to a first output and includes a first transformer having a first primary winding. The second power converter is also adapted to convert the input to a second output and includes a second transformer having a second primary winding. The second primary winding of the second transformer is not the first primary winding of the first transformer. The shared clamp reset circuit is coupled to the first primary winding of the first transformer and is coupled to the second primary winding of the second transformer to manage leakage inductance energy within the first transformer and within the second transformer.

Abstract: A fast startup switching converter comprises a first switch, a second switch, a third switch, a first capacitor, and a controller controlling the ON and OFF switching of the second and third switches. The first terminal of the first switch is coupled to the input terminal of the switching converter, the second terminal is coupled to the first terminal of the second switch. The first terminal of the third switch is coupled to the second terminal of the first switch and the first terminal of the second switch. The first capacitor is coupled to the second terminal of the third switch and the controller to provide a power supply voltage for the controller. The switching converter charges the first capacitor through the first and third switches in a first working state, and transfers energy to a load through the first and second switches in a second working state.

Abstract: A lighting device which supplies power to an electrode of a discharge lamp to turn on the discharge lamp includes: a pulse generating circuit which produces a high-voltage pulse and applies the high-voltage pulse to the electrode; wherein the pulse generating circuit includes an inductor whose output end is connected with the electrode, and a capacitor connected with the output end of the inductor to produce free oscillation of current applied to the electrode in cooperation with the inductor.

Abstract: Representative implementations of devices and techniques determine the timing of switches associated with a dc-dc converter. The determination is based on a body diode conduction of at least one of the switches, which is detected and used to determine a switching delay.