Abstract: A detector compares a drain voltage with a first threshold voltage and outputs a first detection signal. An ON-counter detects a period of time during which current flows in a switching circuit based on the first detection signal, counts the period of time based on a predetermined clock cycle, and outputs an ON-count value. A first comparator receives the ON-count value and an ON-threshold value and outputs a first comparison signal when the ON-count value and the ON-threshold value match. A second comparator receives the ON-count value and a decreased ON threshold value, compares the ON-count value and the decreased ON-threshold value, and outputs a second comparison signal. An ON-mask time adjuster receives the second comparison signal and outputs an ON-threshold value for adjusting a mask time and a decreased ON-threshold value that is less than the ON threshold value.

Abstract: A switching power supply, a power adapter and a charger are provided. The switching power supply comprises a current-mode PWM control unit, a transformer, and a DC power supply circuit connected in series to a power compensation auxiliary circuit. The current-mode PWM control unit comprises a current detection terminal. An input of the DC power supply circuit is connected to an auxiliary voltage output. The auxiliary voltage output outputs an auxiliary voltage related to output voltage of the switching power supply. The power compensation auxiliary circuit is used to compare the output voltage and a threshold voltage. When the current output voltage of the switching power supply is not greater than the threshold voltage, the power compensation auxiliary circuit generates a DC voltage, thus providing a compensation voltage to the current detection terminal, otherwise no compensation voltage is provided.

Abstract: A switch control circuit and a switch control method are provided. In this circuit, compositions that sense a drain voltage of a switch device are added in a QR Buck Converter switch control circuit. A first resistor, a second switch, a second resistor are electrically connected to a drain terminal of a switch device to sense the 0 A state of an inductor current. On the basis of a detection result, the switch control circuit turns on the switch device when an inductor current is 0 A, and a drain sensing voltage (ZCD) is less than a predetermined reference voltage (REF).

Abstract: A driving circuit and a driving method are provided. The driving circuit includes a power stage circuit and a full-bridge circuit. The power stage circuit is configured to receive an input voltage, and generate an output voltage at an output port of the power stage circuit. The full-bridge circuit is coupled to the output port of the power stage circuit and is configured to perform charging and discharging on a piezoelectric load. An operating mode of the full-bridge circuit is controlled, so that a supply voltage signal for driving the piezoelectric load during a first operating interval of an operating cycle corresponds to a reference voltage in a first interval, and the supply voltage signal during a second operating interval of the operating cycle corresponds to the reference voltage in a second interval. The driving circuit has a small volume, which is conducive to circuit integration.

Abstract: The invention discloses a control method in use of a synchronous rectifier controller, controlling a synchronous rectifier in a power supply supplying power a load. The synchronous rectifier is turned ON in response to a terminal signal of the synchronous rectifier. An ON-time of the synchronous rectifier is made not less than a minimum ON-time. A detection result in association with the load is provided, for determining the minimum ON-time. The minimum ON-time is a first period when the detection result indicates the load as a first load, and a second period, shorter than the first period, when the detection result indicates the load as a second load heavier than the first load.

Abstract: The present application provides a detecting method of an operating state of a power supply and a detecting apparatus, where the power supply includes a primary circuit, a transformer and a secondary circuit. The secondary circuit includes a secondary current detecting unit, a temperature detecting unit and a secondary controlling unit. Firstly the secondary current detecting unit detects a current value of the secondary circuit, then the secondary controlling unit compares the current value of the secondary circuit with a preset current threshold. When the current value of the secondary circuit is less than or equal to the preset current threshold, the temperature detecting unit detects a temperature value of the power supply and the secondary controlling unit determines the operating state of the power supply according to the acquired temperature value of the power supply.

Abstract: The present disclosure provides a power supply control device. The power supply control device includes a feedback voltage generator, an on-timing setting unit and an off-timing setting unit. The feedback voltage generator is configured to generate a feedback voltage by sampling a primary voltage of a transformer that forms an insulated switching power supply. The on-timing setting unit is configured to turn on a primary current of the transformer based on a comparison result between the feedback voltage and a slope-shaped reference voltage. The off-timing setting unit is configured to turn off the primary current after a predetermined on time has elapsed since the primary current was turned on. A sampling timing of the primary voltage is set based on an on timing of the primary current.

Abstract: Controller and method for charging one or more loads. For example, the controller for charging one or more loads includes: a controller terminal configured to be biased at a first voltage related to a second voltage of a secondary winding of a power converter, the power converter further including a primary winding coupled to the secondary winding, the power converter being configured to, if the power converter is not unplugged from a voltage supply for an AC input voltage, receive the AC input voltage represented by the second voltage and output an output power to the one or more loads; and a voltage detector configured to: process information associated with the first voltage; and determine whether the AC input voltage is in a first voltage state or in a second voltage state based at least in part on the first voltage.

Abstract: A power converter with over temperature protection compensation includes a main conversion unit, a primary-side control unit, a primary detection circuit, and an over temperature adjustment circuit. The primary-side control unit obtains a primary voltage change value through the primary detection circuit, and the primary-side control unit correspondingly provides a current change value to the over temperature adjustment circuit according to the primary voltage change value. The over temperature adjustment circuit provides a temperature control voltage according to the current change value so that the primary-side control unit determines whether an over temperature protection is activated according to the temperature control voltage.

Abstract: A multiport USB-PD adaptor including a flyback-converter, a USB controller including a USB-PD subsystem and buck-controller, and multiple buck and bypass-circuits, and methods for operating the same are provided. Generally, the adaptor is operated in a buck-bypass-mode, in which at least one buck-circuit is bypassed and the flyback-converter is operated to generate an input voltage (VIN) to the buck-circuits equal to a requested output voltage (VOUT_C), which is then coupled directly to the associated port. Buck-circuits coupled to other active ports can also be bypassed if the requested VOUT_Cs are the same, or the buck-circuits operated to provide another VOUT_C. If a bypass-circuit unavailable, the adaptor is operated in a variable-buck-input-mode by determining a highest VOUT_C requested on any port and setting VIN to a sum of the highest VOUT_C and an offset voltage. Buck-circuits coupled to active ports are then operated to provide the requested output voltages.

Abstract: An integrated circuit for a power supply circuit that includes a transformer and a transistor. The integrated circuit includes a first terminal receiving a voltage corresponding to a coil voltage across an auxiliary coil of the transformer when the transistor is off, a second terminal receiving a feedback voltage corresponding to an output voltage of the power supply circuit, a third terminal receiving a voltage that corresponds to a current flowing through the transistor and the coil voltage respectively when the transistor is on and off, a detection circuit configured to detect whether the voltage at the third terminal when the transistor is off is lower than a reference voltage, and a control circuit configured to control switching of the transistor based on the feedback voltage, the voltage at the third terminal when the transistor is on, and a detection result of the detection circuit.

Abstract: A control circuit for an isolated power converter includes a first sensing circuit that senses a secondary side output voltage and produces a pulse wave modulation (PWM) signal having a duty cycle that is proportional to a value of the secondary side output voltage. The PWM is transferred across the converter isolation barrier to the primary side, and a primary side circuit receives the PWM signal and outputs a control signal. A controller determines the value of the secondary side output voltage from the control signal and uses the value to control primary side power switching devices of the isolated power converter to regulate the secondary side output voltage at a selected value.

Abstract: A method involves determining that a power converter is in a no-load or ultra-light load mode of operation. In response to determining that the power converter is in a no-load or ultra-light load mode of operation, a voltage amplitude of a feedback signal of the power converter is allowed to rise towards a voltage amplitude that is greater than or equal to a first threshold voltage level. Upon determining that the voltage amplitude of the feedback signal is greater than or equal to the first threshold voltage level, a first sequence of enabling pulses are issued to a primary side switch of the power converter to reduce a voltage amplitude of the feedback signal. Upon determining that the voltage amplitude of the feedback signal is greater than or equal to a second threshold voltage level, a normal mode of operation of the power converter is entered.

Abstract: A multi-converter switching power supply includes a first switching converter with a first output capacitor, a second switching converter with a second output capacitor, a bypass switch coupled across the second output capacitor, and a bypass control circuit for controlling the bypass switch. Input terminals of the first and switching converters are coupled in parallel, while output terminals of the first and switching converters are coupled in series to provide a total output voltage to a load. When detecting that the second output voltage approaches a negative voltage, the bypass control circuit turns on the bypass switch, so as to protect the second output capacitor from being damaged by a reverse DC voltage.

Abstract: An embodiment DC switching converter comprises first and second Zeta converters, each comprising an input stage, an output stage, a first switching stage, and a second switching stage. The input stage of each Zeta converter comprises a respective input inductor having a first terminal electrically coupled to the respective first switching stage. The input inductors of the input stages of the first and second Zeta converters are magnetically coupled in such a way that when current enters the terminal of the input inductor of the first Zeta converter that is coupled to the first switch stage of the first Zeta converter, a voltage induced by the coupled current is positive at the terminal of the input inductor of the second Zeta converter that is coupled to the first switching stage of the second Zeta converter.

Abstract: An embodiment of the invention includes a non-transitory computer-readable medium storing instructions that, when executed by a computer, cause the computer to carry out a method for scheduling at least one activity to achieve a time-varying energy balance of a power system. A mission plan for a mission is received. The mission plan includes at least one activity and at least one route. Each route of the at least one route includes at least one time and at least one location. A plurality of power load identifications is received for at least one time-varying power load for use in the mission plan. A plurality of energy storage device identifications is received for at least one energy storage device. Based on the plurality of power load identifications, a power requirement required to complete the mission plan is determined using the at least one power load. Based at least in part on the mission plan and the plurality of energy storage device identifications, an available power for the mission is determined.

Abstract: Systems and methods are provided for regulating a power converter. An example system controller includes: a driver configured to output a drive signal to a switch to affect a current flowing through an inductive winding of a power converter, the drive signal being associated with a switching period including an on-time period and an off-time period. The switch is closed in response to the drive signal during the on-time period. The switch is opened in response to the drive signal during the off-time period. A duty cycle is equal to a duration of the on-time period divided by a duration of the switching period. One minus the duty cycle is equal to a parameter. The system controller is configured to keep a multiplication product of the duty cycle, the parameter and the duration of the on-time period approximately constant.

Abstract: System controller and method for regulating a power converter. For example, the system controller includes a first controller terminal and a second controller terminal. The system controller is configured to receive an input signal at the first controller terminal and generate a drive signal at the second controller terminal based at least in part on the input signal to turn on or off a transistor in order to affect a current associated with a secondary winding of the power converter. Additionally, the system controller is further configured to determine whether the input signal remains larger than a first threshold for a first time period that is equal to or longer than a first predetermined duration.

Abstract: A power converter with over temperature protection compensation includes a main conversion unit, a primary-side control unit, a secondary-side control unit, a secondary detection circuit, and an over temperature adjustment circuit. The secondary-side control unit obtains a secondary voltage change value through the secondary detection circuit, and the secondary-side control unit correspondingly provides a current change value to the over temperature adjustment circuit according to the secondary voltage change value. The over temperature adjustment circuit provides a temperature control voltage according to the current change value so that the secondary-side control unit determines whether an over temperature protection is activated according to the temperature control voltage.

Abstract: A switching control circuit for controlling switching of a transistor in a power supply circuit, such that the power supply circuit generates an output voltage at a target level. The switching control circuit includes an overload detection circuit detecting that a load of the power supply circuit is in an overload condition, when a voltage according to the output voltage reaches a predetermined level, an overcurrent detection circuit detecting that a load current is an overcurrent, when a current according to the load current reaches a predetermined value, an adjustment circuit decreasing the predetermined value, when a first time period has elapsed since the load becomes in the overload condition, a drive circuit driving the transistor such that the output voltage reaches the target level, and a control circuit causing the drive circuit to stop driving the transistor, after the load becomes in the overload condition or the load current becomes the overcurrent.

Abstract: A power supply circuit includes a power converter, an input voltage source, and a clamping circuit. The power converter has an input pin, an output pin, and an enable pin. The input voltage source is electrically connected to the input pin, and provides an input voltage to the input pin. The clamping circuit is electrically connected to the enable pin of the power converter. When the input voltage increases to at least a threshold input voltage, the clamping circuit is configured to activate the power converter to provide an output voltage at the output pin. When the input voltage decreases below the threshold input voltage, the clamping circuit is configured to deactivate the power converter and prevent the power converter from being re-activated within a predefined time period.

Abstract: A fast charging device for mobile electronic device is disclosed. Particularly, an input-end filtering unit contained in the fast charging device is designed to comprise two first input capacitors, one second input capacitor, and one switch element. By such design, in case of a rated voltage of an input AC power being smaller than 110 Vac, the switch element is controlled to complete a switch-ON operation, so as to make the input-end filtering unit execute a signal filtering process by simultaneously using two first input capacitors and one second input capacitor. Moreover, in case of the rated voltage of the input AC power being in a range between 110 Vac and 264 Vac, the switch element is controlled to complete a switch-OFF operation, so as to make the input-end filtering unit execute the signal filtering process by merely using two first input capacitors.

Abstract: In one embodiment, a power supply circuit has a power source, an inductor in series with a switching transistor connected to the power source, a pair of isolation capacitors connected across the switching transistor, a load connected to the isolation capacitors such that they isolate the load from low frequency energy from the power source, and a resonance circuit configured to amplify resonant ringing connected at least one of in parallel to the inductor or in parallel to the switching transistor.

Abstract: An isolated switching converter has a primary switch and a control circuit. The control circuit has a first sampling circuit, a second sampling circuit, a compensation circuit and a feedback control circuit. The first sampling circuit is coupled to an auxiliary winding of a transformer to receive a voltage on the auxiliary winding and is configured to generate a first feedback signal having an alternating current signal indicative of an output voltage. The second sampling circuit is coupled to the auxiliary winding through a first rectifier and is configured to generate a second feedback signal having a direct current signal indicative of the output voltage. The compensation circuit is configured to generate a compensation signal based on the first feedback signal, the second feedback signal and a reference threshold. The feedback control circuit is configured to generate a primary control signal of the primary switch based on the compensation signal.

Abstract: An active clamp circuit includes an active clamp switch having a drain node and a source node, an active clamp capacitor coupled in a series combination with the active clamp switch, a delay circuit, and an active clamp controller circuit coupled to the active clamp switch and to the delay circuit. The active clamp controller circuit is configured to i) receive an active clamp switch voltage based on a voltage developed across the drain node and the source node of the active clamp switch, ii) enable the active clamp switch based on a voltage amplitude of the active clamp switch voltage, and iii) disable the active clamp switch based on a delay signal generated by the delay circuit.

Abstract: A switching control circuit for controlling a power supply circuit having a transformer and a transistor. The switching control circuit is configured to operate based on a power supply voltage that corresponds to a voltage from an auxiliary coil of the transformer. The switching control circuit includes a drive signal output circuit that outputs a drive signal that corresponds to an operation mode of the power supply circuit, the operation mode including a burst mode, a drive circuit that performs switching of the transistor based on the drive signal outputted by the drive signal output circuit, and a control circuit that outputs, to the drive signal output circuit, a control signal for operating the power supply circuit in the burst mode, when a first transition condition or a second transition condition is satisfied, the first transition condition including time as a condition, and the second transition condition not including time as a condition.

Abstract: An LLC resonant converter is provided, which includes an input power source, a full-bridge switch circuit, a resonant circuit, a transformer, a rectifier circuit, a load, and a control circuit. The control circuit includes a load detection circuit and a valley switching circuit. The load detection circuit detects a load state of the load. The valley switching circuit is configured to, in response to the load state being a light load state: correspondingly generate a first difference voltage; calculate a first switch on-time for a first switch and a fourth switch; generate switching signals that control the first switch and the fourth switch to be turned off, and detect voltage valleys of a second switch and a third switch; and generate the switching signals to control the second switch and the third switch to be turned on according to the calculated first switch on-time.

Abstract: Provided is a dynamic control method that turns off a primary-side switching transistor when an output voltage exceeds an upper limit, and control the switching of a secondary-side synchronous rectification transistor with a fixed cycle and a fixed duty cycle. During the time that the synchronous rectification transistor is turned on, the energy of a load capacitor at the output end is extracted to the primary side, which causes the output voltage to drop rapidly and the overshoot voltage to decrease greatly.

Abstract: The invention mainly relates to a rotating electrical machine (10) comprising: a rotor (12) provided with a rotor winding (13); a stator (11) provided with a winding (14) having a plurality of phases; a converter (16) comprising rectifying components (17) to which the phases of the stator (11) are connected; a voltage regulator (24) for adapting an excitation current (lexc) applied to the rotor winding (13) according to a difference between an output voltage (Liait) and a reference voltage; at least one current sensor (27) arranged at the output of the rotating electrical machine (10) or on at least one phase of the rotating electrical machine (10); and a diagnostic module (30) that can detect a malfunction of the rotating electrical machine (10) on the basis of a current measurement provided by the current sensor (27).

Abstract: A light source device includes a light source unit having a dielectric barrier discharge lamp and a lighting circuit. The lighting circuit includes a transformer; a switching element; a controller for the switching element; a detector that detects current flowing through or voltage on a primary or a secondary side of the transformer; and a determination unit. The controller is configured to enable performing a steady-state operation of controlling ON/OFF of the switching element at a steady-state operation frequency (f1) to steadily light the dielectric barrier discharge lamp; and a determination operation of controlling ON/OFF of the switching element at a determination operation frequency (f2) higher than the steady-state operation frequency (f1), and the determination unit determines whether or not to stop the lighting operation based on the current or the voltage detected by the detector when the controller controls the switching element at the determination operation frequency (f2).

Abstract: A system includes an isolated converter having a power transformer with a primary winding, a secondary winding, and an auxiliary winding. The system also includes: 1) a first switch coupled to the primary winding; 2) a switch controller coupled to the first switch; and 3) a bias power regulator circuit coupled to the auxiliary winding and the switch controller. The bias power regulator circuit includes a second switch. The bias power regulator circuit is configured to provide a bias supply output voltage to the switch controller based on a first set of modes that modulate a switching frequency of the second switch and based on a second mode in which the second switch stays off.

Abstract: [Problem] An object is to provide an inverter circuit that can improve the efficiency and stabilize the operation, the inverter circuit executes normal control when the output voltage rises, even when the output frequency is low, and the inverter circuit divides the normal control and regenerative control operations so that the regenerative control is executed when the output voltage drops. [Solution] When the error value is greater than or equal to the first threshold value, the control unit of the inverter circuit executes a normal control of the capacitive load, by operating the primary side switch with the secondary side switch turned off, and on the other hand, when the error value is less than the first threshold value, the control unit executes a regenerative control to the direct current power supply, by operating the secondary side switch with the primary side switch turned off.

Abstract: In some examples, a circuit includes an input circuit, an output circuit, an auxiliary circuit, and a balancing circuit. The input circuit comprises a primary capacitor coupled to primary windings of a transformer. The output circuit comprises a secondary capacitor coupled to secondary windings of the transformer, wherein the secondary windings are coupled to the primary windings. The auxiliary circuit comprises auxiliary windings coupled to the primary windings. The balancing circuit is coupled to the output circuit, the auxiliary circuit, and the input circuit. The balancing circuit is configured to balance a voltage across the primary capacitor with a voltage across the secondary capacitor.

Abstract: Disclosure includes a control method in use of a switching-mode power supply that supplies an output voltage to a load. A line voltage generated by rectifying an alternating-current voltage is detected to compare with a first reference voltage. A control signal is generated in response to the comparison of the line voltage and the first reference voltage. When the line voltage is less than the first reference voltage, the control signal is used to increase converted power that the switching-mode power supply provides to the output voltage. When the line voltage is not less than the first reference voltage, the control signal has no influence to the converted power.

Abstract: A method and a control circuit for driving an electronic switch coupled to an inductor in a power converter in successive drive cycles each including an on-time and an off-time are disclosed. Driving the electronic switch includes: measuring an inductor voltage during the on-time in a drive cycle in order to obtain a first measurement value; measuring the inductor voltage during the off-time in a drive cycle in order to obtain a second measurement value; obtaining a first voltage measurement signal that is dependent on a sum of the first measurement value and the second measurement value; and adjusting the on-time in a successive drive cycle dependent on a feedback signal and the first voltage measurement signal.

Abstract: The disclosure discloses a bus voltage secondary ripple suppression method and a bus voltage secondary ripple suppression device. The method includes: determining a current working mode of an inverter Boost circuit; wherein the working mode includes a continuous current mode (CCM) and a discontinuous current mode (DCM); calculating an output compensation amount according to the current working mode of the inverter Boost circuit; superimposing the output compensation amount on a control output amount of the Boost circuit; and controlling the Boost circuit by a control output amount superimposed with an output compensation amount. According to the scheme of this embodiment, the third harmonic in the output current of the inverter is reduced, and the current output quality of the inverter is improved.

Abstract: A highly integrated switching power supply and a control circuit are provided. The switching power supply includes a transformer, the transformer comprises a primary winding, a secondary winding and an auxiliary winding, and the control circuit includes: a power switch transistor, configured to control disconnection and conduction of the primary winding of the transformer; a primary current sampling module, configured to sample a current of the primary winding to generate a sampling voltage; and a voltage stabilization control module, configured to turn on or turn off the power switch transistor according to an input voltage, an output voltage of the switching power supply system, and the sampling voltage.

Abstract: The present disclosure provides a power supply circuit and a display apparatus. The power supply circuit includes a power management integrated circuit. The power management integrated circuit includes a driving pin configured to transmit a drive signal. The power management integrated circuit includes a power transistor with a control terminal connected to the driving pin, a first terminal connected to a first power source, and a second terminal connected to a load. The power transistor is configured to supply a voltage to the load.

Abstract: The present invention provides a power controller, a power supply system and device and control method thereof. The power command value is adjusted according to the state of the power supply system and the characteristic of the secondary battery. When the converting power of the power converter is larger than or equal to the power command value, or when the charging current is smaller than the minimum charging current, the power controller performs the power adjusting mode for providing the first preset output current value. The power converter adjusts the converting power according to the first preset output current value. When the charging current is larger than or equal to the maximum charging current, the power controller performs the charging control mode for providing the second preset output current value. The power converter adjusts the output current according to the second preset output current value.

Abstract: Embodiments include systems, methods, and apparatuses for controlling off-time during a burst mode in an LLC converter. In one embodiment, a circuit comprises an LLC converter having a primary side and a burst mode controller, the burst mode controller configured to monitor, on the primary side of the LLC converter, electrical current, and in response to a determination that the electrical current is below a first threshold, increase an off-time for switches in the LLC converter and in response to a determination that the electrical current is above a second threshold that is higher than the first threshold, decrease the off-time for the switches in the LLC converter.

Abstract: A dual-mode active clamp flyback converter includes a transformer circuit, a clamping energy storage circuit, and a main switch circuit. The transformer circuit is coupled to a load, and the transformer circuit includes an auxiliary winding. The clamping energy storage circuit is coupled to the transformer circuit. If the load as a heavy loading, the clamping energy storage circuit is turned on. If the load as a light loading, the clamping energy storage circuit is turned off. The main switch circuit is coupled to the transformer circuit. When the main switch circuit is turned on, the auxiliary winding releases energy to a primary-side winding of the transformer circuit.

Abstract: An apparatus is disclosed for improving zero voltage switching (“ZVS”) of a converter circuit such as an active clamp flyback converter. The apparatus includes a first timing circuit acting as the TD(L-H) optimizer, which uses the zero-crossing of the auxiliary winding voltage directly to adaptively vary the dead time. A second timing circuit acting as the TD(H-L) optimizer adaptively varies the dead time with a simple piece-wide linear function as an approximation of the complex optimal equation. A third timing circuit acting as the TDM optimizer contains a charge-pump circuit that adaptively adjusts the ON time of the clamp switch based on the zero-voltage detection of switching node voltage and feed-forwards the input voltage signal to enhance tuning speed so that the correct amount of negative magnetizing current is generated to improve zero voltage switching.

Abstract: The present disclosure is applied to touch technology, and provides an integrating circuit. The integrating circuit comprises an impedance unit, an amplifier, an integration capacitor, a discharge capacitor, a first switch and a second switch. The amplifier comprises a first input terminal, a second input terminal and an output terminal configured to output an output signal; the integration capacitor is coupled between the first input terminal and the output terminal; the first switch is coupled between the first input terminal of the amplifier and the second terminal of the discharge capacitor; and the second switch is coupled between the first terminal and the second terminal of the discharge capacitor.

Abstract: Methods and systems for providing electrical power using an isolated DC-DC converter include: using a power supply to provide multiple amplitudes of open loop current to a primary side of a transformer. The amplitudes are selected to increase stepwise, at predetermined times, to ramp a voltage across output terminals connected to a secondary side of said transformer so that after said power supply provides a maximum open loop current amplitude, said voltage reaches a threshold sufficient to enable a closed loop controller connected to said output terminals to send a feedback signal to said primary side. The threshold voltage is insufficient to fully power said output terminals. The feedback signal is selected to control said power supply to increase current to said primary side at closed loop current levels until said output terminals are fully powered.

Abstract: A power transfer device includes an oscillator circuit of a DC/AC power converter responsive to an input DC signal and an oscillator enable signal to generate an AC signal. The oscillator circuit includes a first node, a second node, and a circuit coupled between the first node and the second node. The circuit includes a cross-coupled pair of devices. The oscillator circuit further includes a variable capacitor coupled between the first node and the second node. A capacitance of the variable capacitor is based on a digital control signal. A first frequency of a pseudo-differential signal on the first node and the second node is based on the capacitance. The power transfer device further includes a control circuit configured to periodically update the digital control signal. A second frequency of periodic updates to the digital control signal is different from the first frequency.

Abstract: In an embodiment, a power supply includes first and second supply input nodes, a supply output node, first and second switch circuits, a filter circuit, and a drive circuit. The first and second supply input nodes are respectively configured to receive first and second input voltages, and the supply output node is configured to provide an output voltage. The first switch circuit has a first conduction node coupled to the first supply input node, a second conduction node, and a control node configured to receive a first control signal, and the filter circuit has a first node coupled to the second conduction node and has a second node. The second switch circuit has a first conduction node coupled to the second node of the filter circuit, a second conduction node coupled to the second supply input node, and a control node.

Abstract: A controller for use in a power converter includes a control loop clock generator that is coupled to generate a switching frequency signal in response to a sense signal representative of a characteristic of the power converter, a load signal responsive to an output load of the power converter, and a hard switch sense output. A hard switch sense circuit is coupled to generate the hard switch sense output in response to the switching frequency signal and a rectifier conduction signal that is representative of a polarity of an energy transfer element of the power converter. A request transmitter circuit is coupled to generate a request signal in response to the switching frequency signal to control switching of a switching circuit coupled to an input of the energy transfer element of the power converter.

Abstract: A controller to regulate an output voltage of a power converter comprising a feedback reference circuit to generate a drive signal to control a power switch in response to the feedback signal and an output power control circuit configured to generate an adjust signal in response to an output current of the power converter and a desired value of an output power of the power converter, the adjust signal adjusts the feedback signal such that the controller regulates the output voltage to achieve the desired value of the output power. The output power control circuit further comprises an analog-to-digital converter (ADC), a calculator circuit, and an update circuit. The ADC provides a measure signal which is a digital representation of the output current, the calculator circuit determines a calculated value of the output voltage, and the update circuit further outputs an update signal to update the adjust signal.

Abstract: Peak primary current control on the secondary side. In a power converter having a primary side and a secondary side separated by a main transformer, example methods include: driving primary current through a primary winding of the main transformer; creating, on the secondary side of the main transformer, a signal indicative of current through the primary winding of the main transformer; and ceasing the driving of primary current through the primary winding when the signal indicative of primary current reaches a predetermined value.

Abstract: A flyback converter includes a primary side circuit to receive an input voltage signal, a secondary side circuit to generate an output voltage signal using the input voltage signal, a synchronous rectifier switch, and a synchronous rectifier controller. The synchronous rectifier controller receives an attenuated drain-source voltage signal of the synchronous rectifier switch and the output voltage signal. The synchronous rectifier controller includes a threshold voltage generator to generate a first voltage signal using the output voltage signal, a first comparator to compare the attenuated drain-source voltage signal to the first voltage signal and, in response, generate a first comparison signal, and a second comparator to compare the attenuated drain-source voltage signal to a second voltage signal and, in response, generate a second comparison signal.