A power converter and an operation method of the power converter are provided. The power converter includes a rectifier, a boost circuit, a current sensor, and a processor. The rectifier rectifies an AC power to generate a rectified power. The boost circuit includes a boost inductor. The boost circuit boosts the rectified power to generate an output power. The current sensor senses an inductor current value at the boost inductor to generate a sensed value corresponding to the inductor current value. The processor generates a first reference value according to an output voltage value of the output power, an input impedance value, and a first value. When the sensed value is greater than the first reference value, the processor enters a first operation mode to cause the sensed value to be not less than the first reference value.

Dispensers and dispensers having refill units with energy on the refill unit energy sources are disclosed herein. An exemplary dispenser includes a housing, a motor for operating a pump, an object sensor, an auxiliary power source, a receptacle for receiving a refill unit and an energy on the refill receiving receptacle. The dispenser further includes a processor, memory, one or more capacitors, an energy on refill voltage boost circuit, a high power voltage buck circuit and a low power regulator circuit. The low power regulator circuit provides power for at least the processor and the object sensor. The capacitors provide power to the high power voltage buck circuit and the low voltage regulator, and the high voltage buck circuit provides power to operate the motor. A refill unit have an energy on the refill energy source may be inserted into the dispenser.

A DC-DC converter has a configuration in which a first full-bridge circuit and a second full-bridge circuit are connected via a transformer and an inductor. A control circuit controls soft switching of each switching element in the first full-bridge circuit and the second full-bridge circuit. An inductor current flowing through an equivalent inductor at a time of switching of turning on or off each switching element is greater than or equal to a threshold current, the equivalent inductor being equivalent to the transformer and the inductor. The control circuit outputs predetermined power by changing a voltage output period of the first full-bridge circuit and a voltage output period of the second full-bridge circuit while fixing the switching frequency and keeping constant a polarity inversion period in which the output of the second full-bridge circuit and the output of the first full-bridge circuit have reverse polarities. This enables performing ZVS operations by simple control and reducing switching losses.

A power converter provides a low-voltage output using a full-bridge fault-tolerant rectification circuit. The output circuit uses controlled switches as rectifiers. A fault detection circuit monitors circuit conditions. Upon detection of a fault, the switches are disabled decoupling the power converter from the system. A common-source dual MOSFET device includes a plurality of elements arranged in alternating patterns on a semiconductor die. A common-source dual synchronous rectifier includes control circuitry powered from the drain to source voltage of the complementary switch. A DC-to-DC transformer converts power from an input source to a load using a fixed voltage transformation ratio. A clamp phase may be used to reduce power losses in the converter at light loads, control the effective output resistance of the converter, effectively regulate the voltage transformation ratio, provide narrow band output regulation, and control the rate of change of output voltage for example during start up. One or more of the transformer windings may be clamped. The converter may use the sine amplitude converter topology. The converter may use common-source dual MOSFET devices and fault detection. The density of point of load power conversion may be increased and the associated power dissipation reduced by removing the input driver circuitry from the point of load where it is not necessary. An output circuit may be located at the point of load providing fault tolerant rectification of the AC power from the secondary winding of a power transformer which may be located nearby the output circuit. The resonant voltage and current waveforms on the primary side of the transformer are readily communicated via an AC bus between the driver circuit and the primary winding of the power transformer. The driver circuit may drive a plurality of transformer-output circuit pairs. The transformer and output circuit may be combined in a single module at the point of load. Alternatively, the output circuit may be integrated into point of load circuitry such as a processor core. The transformer may be deployed near the output circuit.

Multiphase power processing circuit and a method for control thereof are disclosed, with which, exchange of data is achievable between a multiphase controller and any of power processing circuits via pins of at least two of the three categories, Enable, PWM and Temperature Indicator, of the multiphase controller. The exchanged data may include, but is not limited to, a phase identifier, an over-current protection threshold, an over-current protection threshold, an over-temperature protection threshold, a current sampling gain, a current sampling bias, a temperature sampling gain, a temperature sampling bias, a drive speed and the like of the power processing circuit. In this way, improvements in system flexibility and security are obtained.

A power supply comprises a power converter having a transformer, a low side switch configured to draw current from a supply voltage through a primary winding of the transformer and a high side switch configured to couple the primary winding of the transformer to a snubber capacitor. A controller is configured to control the power converter by generating drive signals that control the opening and closing of the high side switch and the low side switch. The controller is configured to selectively control the high side switch according to various modes of operation depending on operating conditions such as input voltage and load power consumption. The modes of operation can include, for example, a mode in which the high side switch is closed and then opened once during each of the series of switching cycles and a mode of operation in which the high side switch is closed and then opened two times during each of the series of switching cycles.

A switching regulator converts an AC input voltage into an output voltage, to power a load. The switching regulator includes a power stage having a main power switch. The main power switch has different ON time durations under different AC input voltage conditions and different load currents.

An embodiment apparatus comprises a switching-type output power stage, a modulator circuit configured for carrying out a pulse-width modulation and converting an electrical input signal into an input signal pulsed between two electrical levels, having a mean value proportional to the amplitude of the input signal, and a circuit arrangement for controlling saturation of an output signal supplied by the switching-type output power stage. The circuit arrangement comprises a pulse-remodulator circuit, between the output of the modulator circuit and the input of the switching-type output power stage, that is configured for supplying, as a driving signal to the switching-type output power stage, a respective modulated signal pulsed between two electrical levels, measuring a pulse width as pulse time interval elapsing between two consecutive pulsed-signal edges of the pulsed input signal, and, if the measurement indicates that the latter is below a given minimum value, remodulating the pulsed input signal.

A converter circuit includes first and second electronic switches coupled at an intermediate node, with an inductor coupled between the intermediate node and an output node. Switching drive control circuitry causes the first and the second electronic switch to switch between a conductive state and a non-conductive state. The drive control circuitry includes a first feedback signal path to control switching of the first and the second electronic switch as a function of the difference between a feedback signal indicative of the signal at the output node and a reference value. A second feedback signal path includes a low-pass filter coupled to the output node and configured to provide a low-pass filtered feedback signal resulting from low-pass filtering of the output signal. The second feedback signal path compensates the feedback signal as a function of the difference between the low-pass filtered feedback signal and a respective reference value.

Methods, apparatus, systems and articles of manufacture are disclosed to adjust an operating mode of a power converter. An example apparatus includes a first transistor having a gate terminal, a first current terminal, and a second current terminal, the first current terminal to be coupled to a second transistor and an inductor of a power converter, a capacitor coupled to the second current terminal, a logic gate having a first logic gate input, a second logic gate input, and a logic gate output, the logic gate output coupled to the gate terminal, a comparator having a comparator input and a comparator output, the comparator input coupled to the capacitor and the second current terminal, a multiplexer coupled to the comparator output, a first flip-flop coupled to the multiplexer and the second logic gate input, and a second flip-flop coupled to the multiplexer and the first flip-flop.