A resonant converter controller circuit is provided. Each period in drive control has a drive time interval and a pause time interval for driving/pausing the resonant converter. The resonant converter controller circuit includes a first oscillating means for generating a clock signal, a second oscillating means for generating a sawtooth wave signal, a third oscillating means for generating a rectangular wave signal, comparison means for outputting a comparison signal indication the rive time interval, by comparing the sawtooth wave signal with a threshold signal, which is generated based on a difference voltage between an output voltage of the resonant converter and a target voltage, and which indicates a ration of the drive time interval to the pause time interval, and a logical operation means for generating a drive control signal based on the comparison signal and the rectangular wave signal to drive and control the resonant converter.

The present embodiments relate generally to DC-DC converters and more particularly to a scheme for providing current sharing between parallel converters in a multiphase configuration. In some embodiments, a cycle-by-cycle instant correction to the compensation signal offset is provided based on the current share error between the paralleled converters so as to achieve improved instant current share performance.

A method for controlling a voltage converter includes the following steps. A feedback compensation signal is generated based on an output voltage of the voltage converter. An output representation signal is compared with a first threshold and a second threshold. A switch control signal to control the turn-on and turn-off of a power circuit of the voltage converter is adjusted based on an ultra-light load feedback value when the output representation signal is less than the first power threshold. The switch control signal is adjusted based on the feedback compensation signal when the output representation signal is greater than the first power threshold. The second threshold is greater than the first threshold, and the ultra-light load feedback value is greater than the feedback compensation signal when the output representation signal is equal to the second threshold.

An embodiment provides a circuit including a transformer having a primary winding coupled to an input port configured to receive an input voltage and a secondary winding configured to provide an output voltage at an output port, controller circuitry configured to switch on and off a current through the primary winding so that energy is transferred to the secondary winding while switching and supply circuitry connected to the controller circuitry, wherein the supply circuitry is coupled to an auxiliary winding of the transformer and configured to provide a supply voltage for the controller circuitry. The controller circuitry is further configured to: transition to a burst mode to switch on and off the current through the primary winding in first bursts, wherein the first bursts are separated by intervals during which switching on and off the current through the primary winding of the transformer by the first bursts is discontinued and provide second bursts during the intervals in order to keep the supply voltage of the controller circuitry between a lower bound value and an upper bound value while the output voltage ramps down to a requested valley value or provide second bursts during the intervals after reaching a timeout limit in order to provide the supply voltage to the controller circuitry while the output voltage ramps down to a requested valley value.

A voltage booster powered by a primary electrical source for providing an adjustable voltage across the load, while a current regulator in series with the load maintains the desired current. When the voltage drop across the current regulator exceeds an upper threshold, the voltage booster's output voltage is reduced to a lower level to reduce the power dissipated by the current regulator, to improve efficiency. When the voltage drop across the current regulator is less than a lower threshold, the voltage booster output is increased to a higher level. In burst mode operation, the voltage booster output alternates between a full voltage and zero voltage, and an optional capacitor provides voltage across the resistive load during discharge. An optional diode can ensure that the capacitor discharges through the load in cases where the voltage booster output is not floating.

A power controller for an LLC resonant converter controls a high-side switch and a low-side switch. An ON-time generator in the power controller determines a high-side ON time of the high-side switch and a low-side ON time of the low-side switch in response to the bigger one between a feedback voltage and a burst voltage, where the feedback voltage is generated in response to an output voltage of the LLC resonant converter. A burst-mode controller in the power controller has a triangular-wave generator providing a triangular-wave signal with an amplitude in association with the burst voltage. A comparator comparing the triangular-wave signal and the feedback voltage to determine a break time when both the high-side and low-side switches are turned OFF. The LLC resonant converter operates in a burst mode when the break time is introduced.

A drive device for driving a load includes: an inverter unit having an upper arm element and a lower arm element and converting electric power supplied to the load; and a charge pump circuit that supplies a gate voltage to the upper arm element. An output voltage of the charge pump circuit is variable according to an inverter input voltage input from an inverter input wiring to a high potential side of the inverter unit.

An active flyback converter is transitioned between a plurality of operational states based on a comparison of a control voltage signal to voltage thresholds and a count of a number of consecutive switching cycles during which a clamp switch is kept off. The plurality of operational states includes a run state, an idle state, a first burst state, and a second burst state. Each set of consecutive switching cycles of the first burst state includes a determined number of switching cycles during which signals are generated to turn the power switch on and off and to maintain an off state of the clamp switch, and a switching cycle in a determined position in the set of switching cycles during which signals are sequentially generated to turn the power switch on, turn the power switch off, turn the clamp switch on and turn the clamp switch off.

The present disclosure relates to an overvoltage protection circuit and a charging device. A voltage applied to a PFC power supply on an input side is collected through an input voltage sampling circuit and an amplifier circuit, and a data processing capability of a charging management circuit is used to determine whether the applied voltage exceeds a preset voltage threshold. The preset voltage threshold refers to a voltage that is not greater than a minimum withstand voltage of an input device of the charger. The power factor correction power supply is controlled to operate to charge the battery to be charged when it is determined that the voltage applied does not exceed the preset voltage threshold, to prevent damage to the input device due to a connection to two phases of voltage.

A method to operate a DC-DC power converter in a low power burst mode, the method including sampling an output voltage of the DC-DC power converter with a sampling frequency to determine when to initiate a burst for the low power burst mode; and adapting the sampling frequency based on the output voltage.