A driving circuit for driving a piezoelectric load, can include: an energy-storage capacitor; a first power stage circuit configured to convert an input voltage into a first voltage, and to store the first voltage in the energy-storage capacitor; a second power stage circuit configured to receive the first voltage to charge the piezoelectric load during a first operation interval of an operation period, such that a power supply voltage signal provided to the piezoelectric load in the first operation interval corresponds to a reference voltage in a first interval; and a discharging circuit configured to discharge the piezoelectric load during a second operation interval of the operation period, such that the power supply voltage signal in the second operation interval corresponds to the reference voltage in a second interval.

A resonant power converter for converting a DC input voltage to AC or DC output voltage, includes a transistor, and a first inductor connected to an input port for a DC voltage to be converted, the drain being connected to the input port by way of the first inductor, the converter furthermore comprising a first resonant network, connected between the drain of the transistor and ground, the first resonant network being configured so as to extract the fundamental component of a drain-source voltage of the transistor and to phase-shift it by a phase shift angle such that the fundamental component and the drain-source voltage are in phase opposition and thus generate a sinusoidal drive signal.

An active-clamped isolated SEPIC DC-DC power converter (ACISC) to convert a DC voltage to supply a variety of DC loads. The single-ended primary-inductor converter (SEPIC) of the ACISC may be configured to perform both buck and boost converter functions. The ACISC of this disclosure may be configured to operate over a wide input voltage range to provide an output voltage for DC electronic loads supplied by the power converter. In the example of an automobile, a back-up twelve volt battery may output voltages to the ACISC over a wide voltage range, e.g., nine volts to eighteen volts. The wide input voltage range of the ACISC may be desirable when used as the converter for a back-up battery supply. The circuitry arrangement and component selection of the ACISC of this disclosure cause the power converter to operate in resonant DCM mode in the megahertz (MHz) frequency range.

A DC-DC converter includes a switch element connected to an input end, a coupling capacitor connected to the switch element at a first node, a first inductor connected to the coupling capacitor at a second node and connected to an output end at a third node, a control circuit that controls the switch element, a second inductor connected to the first node and a ground, a first diode connected to the second node and the ground, a smoothing capacitor connected to the third node and the ground, a comparator, a second diode connected to the second node and the comparator to supply a power voltage powering the comparator, and an output capacitor connected to the second diode and the ground. The comparator compares a voltage at the output end with a reference voltage so as to output a comparison result to the control circuit. This DC-DC converter operates stably.

A portable power pack having a housing, a rechargeable lithium battery positioned in the housing, a liquid crystal display (LCD), a wireless charging coil, a light emitting diode (LED) flash light, a universal serial bus (USB) port, a direct current (DC) port, and a power management circuit. The LCD can be positioned on the housing and configured to display a status of the portable power pack. The wireless charging coil can be positioned in or on the housing and configured to wirelessly couple with an external wireless charging coil of an external device through electromagnetic induction in accordance with, for example, the Qi wireless power transfer standard. The USB port supplies a charging current to charge a portable electronic device, while the DC port supplies a starting current to jump start an engine of a vehicle that is electrically coupled with an external battery. The power management circuit operatively coupled to the wireless charging coil and the rechargeable lithium battery and configured to output the charging current or the starting current.

A light emitting load driving device includes a first constant current source structured to be serially connected to a first light emitting load group; a second constant current source structured to be serially connected to a second light emitting load group; a first load connection terminal structured to be connected to the first light emitting load group; a second load connection terminal structured to be connected to the second light emitting load group; and a control circuit structured to be supplied a first voltage applied to the first load connection terminal, a second voltage applied to the second load connection terminal, and a reference voltage applied to the control circuit, wherein the control circuit is structured to select a minimum voltage between the first voltage and the second voltage, and the control circuit is structured to equalize the minimum voltage and the reference voltage.

A three-port converter with a wide input range and a control method thereof are provided, which relates to a technical field of power electronic converters. The converter is provided with three ports of a photovoltaic cell PV, a storage battery Bat and a resistance load R, and includes a boost circuit (Boost) and a reversible boost-buck circuit (Sepic-Zeta). The boost circuit is configured to connect the photovoltaic cell PV and the load R; and the reversible boost-buck circuit is configured to connect the photovoltaic cell PV, the storage battery Bat, the storage battery Bat and the load R. The three-port converter of the present disclosure has advantages of a small size, a wide input range, a high integration level, high stability, high conversion efficiency, etc.

A portable power pack having a housing, a rechargeable lithium battery positioned in the housing, a liquid crystal display (LCD), a wireless charging coil, a light emitting diode (LED) flash light, a universal serial bus (USB) port, a direct current (DC) port, and a power management circuit. The LCD can be positioned on the housing and configured to display a status of the portable power pack. The wireless charging coil can be positioned in or on the housing and configured to wirelessly couple with an external wireless charging coil of an external device through electromagnetic induction in accordance with, for example, the Qi wireless power transfer standard. The USB port supplies a charging current to charge a portable electronic device, while the DC port supplies a starting current to jump start an engine of a vehicle that is electrically coupled with an external battery. The power management circuit operatively coupled to the wireless charging coil and the rechargeable lithium battery and configured to output the charging current or the starting current.

A power converter comprising a single-ended primary-inductor converter (“SEPIC”) includes a first inductive element (L1) and a second inductive element (L2) that are arranged, in the usual way, to provide a first, non-isolated load. The power converter further includes an isolated load circuit comprising a third inductive element (L3) connected to a second output for delivery a second, isolated load. The third inductive element (L3) is coupled to the first inductive element (L1) and/or the second inductive element (L2) to transfer power to the isolated load circuit to deliver the second load, and wherein the first inductive element (L1), the second inductive element (L2) and the third inductive element (L3) are each wound around a single magnetic core.

A converter that makes it possible to selectively switch between various converter architectures that are capable of supplying different output voltages on the basis of one and the same input voltage. The various architectures share at least some electronic components with one another, thereby decreasing the production cost of the converter according to the invention. The converter is particularly advantageous for lighting modules for motor vehicles, in which there are substantial space constraints but in which wide output-voltage ranges are required to be able to supply a varied and substantial number of electroluminescent light sources (LEDs) with power.