A circuit portion is provided which includes an energy harvesting device producing a DC output; a DC-DC converter having an input connected to the DC output of the energy harvesting device; an output for connection to a load; and a monitoring module including a non-ohmic semiconductor element. The monitoring module is arranged to derive information relating to an output current flowing from the DC-DC converter by measuring a current through the non-ohmic semiconductor element. The monitoring module is arranged to adjust one or more parameters of the DC-DC converter based on the information relating to said output current flowing from the DC-DC converter.

According to one aspect of the present disclosure, there is provided a power converter apparatus that includes at least two switching bridges connected to a Direct Current (DC) bus and both generating pulse-width-modulated (PWM) voltages to non-isolated outputs, and an isolation transformer having a primary winding connected across the outputs of the two switching bridges and a secondary winding connected to isolated outputs. In a non-isolated mode, the two switching bridges are configured to operate in a parallel mode, and power is transferred between the DC bus and the non-isolated outputs. In an isolated mode, the two switching bridges are configured to operate in a full bridge mode, and power is transferred between the DC bus and the isolated outputs through the transformer.

Described are circuits and techniques to increase the efficiency of radio-frequency (rf) amplifiers including rf power amplifiers (PAs) through “supply modulation” (also referred to as “drain modulation” or “collector modulation”), in which supply voltages provided to rf amplifiers is adjusted dynamically (“modulated”) over time depending upon the rf signal being synthesized. For the largest efficiency improvements, a supply voltage can be adjusted among discrete voltage levels or continuously on a short time scale. The supply voltages (or voltage levels) provided to an rf amplifier may also be adapted to accommodate longer-term changes in desired rf envelope such as associated with adapting transmitter output strength to minimize errors in data transfer, for rf “traffic” variations.

Methods and apparatus for continuous conduction mode operation in multi-output power converters are described herein. During a switching cycle, secondary current may be delivered via a diode to a secondary output. Prior to beginning a subsequent switching cycle, a diverting current may be provided to a lower voltage secondary output on a parallel path. In this way diode current may be reduced to substantially zero prior to the subsequent switching cycle.

A power apparatus applied in a solid state transformer structure includes an AC-to-DC conversion unit, a first DC bus, and a plurality of bi-directional DC conversion units. First sides of the bi-directional DC conversion units are coupled to the first DC bus. Second sides of the bi-directional DC conversion units are configured to form at least one second DC bus, and the number of the at least one second DC bus is a bus number. The bi-directional DC conversion units receive a bus voltage of the first DC bus and convert the bus voltage into at least one DC voltage, or the bi-directional DC conversion units receive at least one external DC voltage and convert the at least one external DC voltage into the bus voltage.

One or more multiphase power converters are connected to a positive electrode and a negative electrode of a power supply via a high potential line and a low potential line, respectively, convert DC power of the power supply into multiphase alternate current power by operations of a plurality of inverter switching elements, and apply a voltage to each of phase windings of a multiphase winding set. A DC rotating machine switch including switches on a high potential side and a low potential side connected in series via a DC motor terminal connected to a second terminal that is an end of the DC rotating machine on an opposite side to a first terminal. The DC rotating machine switch generates a voltage of the DC motor terminal variable by switching. A control unit controls operations of the inverter switching elements and the DC rotating machine switch.

A multiple output voltage generator includes a voltage divider and first and second voltage converters. The voltage divider receives a power voltage and divides the power voltage to generate a first output voltage. The first and second voltage converters are coupled to the voltage divider in parallel. The first voltage converter and the second voltage converter converting the first output voltage to respectively generate a second output voltage and a third output voltage.

An apparatus such as a power converter includes a first flying capacitor operative to store a first flying capacitor voltage; a second flying capacitor operative to store a second flying capacitor voltage; an inductor providing coupling between the first flying capacitor and the second flying capacitor; and a network of switches operative to, in accordance with control signals, produce an output voltage via the first flying capacitor voltage and the second flying capacitor voltage.

A charger device includes a Single-Input-Multiple-Output (SIMO) device and a controller. The SIMO device includes a first transistor connected to an input and a first end of an inductor, a second transistor connected to ground and the first end of the inductor, a third transistor connected to a second end of the inductor and a first output, and a fourth transistor connected to the second end of the inductor and a second output. The controller is connected to the SIMO device and is configured to cause the SIMO device to charge the inductor using a first power source coupled to the input during a first time period and discharge the inductor to charge a second power source coupled to the first output during a second time period.

An inductor-less power converter for converting an input voltage at an input terminal to an output voltage at an output terminal is provided, with a conversion ratio between the input and output voltage. The converter can be an inductor-less power converter which is configured for Direct Current, DC, to DC, DC-DC conversion of an input voltage to an output voltage. The input voltage is provided at an input terminal pair whereas the output voltage is provided at an output terminal pair. The ratio between the input voltage and the output voltage defines the conversion ratio, which may be either larger than one or smaller than one, meaning that the voltage may be stepped-up or stepped-down and thus increased or lowered.