44425results about "Dc-dc conversion" patented technology

A high efficiency power converter comprises a boost converter for converting an input voltage to a first voltage on a first output, a buck converter for converting the input voltage to a second voltage on a second output, a linear regulator for converting the first voltage to a third voltage on the second output when the second voltage is lower than a first threshold, and a voltage detector for detecting the input voltage for preventing a reverse current flowing from the second output to the buck converter when the input voltage is lower than a second threshold.

A DC power source unit supplies a DC voltage to a power tool through an adapter when a power switch of the tool is turned ON and also charges a battery pack used as an alternative power source of the tool when the power tool is not operated. In order to prevent a rush current from flowing in a switch interposed between a switching power source circuit and the battery pack when charging the battery pack is commenced, the switch is rendered OFF when the output voltage from the switching power source is greater than the battery voltage. Charging the battery is started upon once lowering the output of the switching power source to a level lower than the battery voltage.

The electromagnetic energy transfer device includes a first resonator structure receiving energy from an external power supply. The first resonator structure has a first Q-factor. A second resonator structure is positioned distal from the first resonator structure, and supplies useful working power to an external load. The second resonator structure has a second Q-factor. The distance between the two resonators can be larger than the characteristic size of each resonator. Non-radiative energy transfer between the first resonator structure and the second resonator structure is mediated through coupling of their resonant-field evanescent tails.

The invention relates to a conditioning circuit that measures operating points of a power supply to deduce therefrom the current-voltage characteristic thereof and to determine directly the voltage corresponding to its maximum power point, without using any kind of tracking algorithm that causes the operating point of the power unit to oscillate about the maximum power point. The maximum power point voltage VMPP is supplied to a controller which regulates a power cell by slaving it to the input voltage until the output voltage of the supply is equal to the maximum power point voltage VMPP. The invention also relates to a solar generator and an associated conditioning method. One particular application is to high-power satellites.

The electromagnetic energy transfer device includes a first resonator structure receiving energy from an external power supply. The first resonator structure has a first Q-factor. A second resonator structure is positioned distal from the first resonator structure, and supplies useful working power to an external load. The second resonator structure has a second Q-factor. The distance between the two resonators can be larger than the characteristic size of each resonator. Non-radiative energy transfer between the first resonator structure and the second resonator structure is mediated through coupling of their resonant-field evanescent tails.

Various embodiments for improved power devices as well as their methods of manufacture, packaging and circuitry incorporating the same for use in a wide variety of power electronic applications are disclosed. One aspect of the invention combines a number of charge balancing techniques and other techniques for reducing parasitic capacitance to arrive at different embodiments for power devices with improved voltage performance, higher switching speed, and lower on-resistance. Another aspect of the invention provides improved termination structures for low, medium and high voltage devices. Improved methods of fabrication for power devices are provided according to other aspects of the invention. Improvements to specific processing steps, such as formation of trenches, formation of dielectric layers inside trenches, formation of mesa structures and processes for reducing substrate thickness, among others, are presented. According to another aspect of the invention, charge balanced power devices incorporate temperature and current sensing elements such as diodes on the same die. Other aspects of the invention improve equivalent series resistance (ESR) for power devices, incorporate additional circuitry on the same chip as the power device and provide improvements to the packaging of charge balanced power devices.

An adaptive current limiter including a conversion network and an amplifier network developing an adaptive current limit signal for use by a switching regulator to limit peak current through an inductor of the switching regulator. The switching regulator develops a pulse control signal for controlling switching of current through the inductor to convert an input voltage to an output voltage. The conversion network provides a limit value by applying a duty cycle of the pulse control signal to a reference value. The amplifier network is configured to develop the adaptive current limit signal based on the limit value. The conversion network may multiply the reference value by the duty cycle to develop the limit value. The amplifier network may include a current source providing a fixed reference current to an amplifier to establish a minimum level of the adaptive current limit signal.

A silicon-on-insulator (SOI) RF switch adapted for improved power handling capability using a reduced number of transistors is described. In one embodiment, an RF switch includes pairs of switching and shunting stacked transistor groupings to selectively couple RF signals between a plurality of input / output nodes and a common RF node. The switching and shunting stacked transistor groupings comprise one or more MOSFET transistors connected together in a “stacked” or serial configuration. In one embodiment, the transistor groupings are “symmetrically” stacked in the RF switch (i.e., the transistor groupings all comprise an identical number of transistors). In another embodiment, the transistor groupings are “asymmetrically” stacked in the RF switch (i.e., at least one transistor grouping comprises a number of transistors that is unequal to the number of transistors comprising at least one other transistor grouping). The stacked configuration of the transistor groupings enable the RF switch to withstand RF signals of varying and increased power levels. The asymmetrically stacked transistor grouping RF switch facilitates area-efficient implementation of the RF switch in an integrated circuit. Maximum input and output signal power levels can be withstood using a reduced number of stacked transistors.

A system and method for combining power from DC power sources. Each power source is coupled to a converter. Each converter converts input power to output power by monitoring and maintaining the input power at a maximum power point. Substantially all input power is converted to the output power, and the controlling is performed by allowing output voltage of the converter to vary. The converters are coupled in series. An inverter is connected in parallel with the series connection of the converters and inverts a DC input to the inverter from the converters into an AC output. The inverter maintains the voltage at the inverter input at a desirable voltage by varying the amount of the series current drawn from the converters. The series current and the output power of the converters, determine the output voltage at each converter.

A logic signal isolator comprising a transformer having a primary winding and a secondary winding; a transmitter circuit which drives said primary winding in response to a received logic signal, such that in response to a first type of edge in the logic signal, a signal of a first predetermined type is supplied to the primary winding and in response to a second type of edge in the logic signal, a signal of a second predetermined type is supplied to said primary winding, the primary winding and the transmitter being referenced to a first ground; and the secondary winding being referenced to a second ground which is galvanically isolated from the first ground and said secondary winding supplying to a receiver circuit signals received in correspondence to the signals provided to the primary winding, the receiver reconstructing the received logic signal from the received signals.