Abstract: A switch mode power supply (SMPS) has optimized efficiency over an entire operating range, from no load to full load, by transitioning between pulse frequency modulation (PFM) and pulse width modulation (PWM) for control of the SMPS depending upon load current. Accurate, smooth, and seamless transitions between PFM and PWM modes of operation occur at a preset load current(s). PFM operation improves efficiency during light load conditions, and PWM has better efficiency at higher load currents. This is advantageous in battery powered applications, and thereby results in a longer time before battery replacement or recharge is necessary.

Abstract: A communication device for use with a power distribution module. The communication device allows multiple different DMX universes to be handled over the same cable that also handles power distribution. A front of house module is provided for powering consoles and receiving DMX inputs from the consoles. Two different consoles can be powered and provide their inputs, and either console can be used to control any or all of the universes.

Abstract: Circuits and methods for dynamic adjustment of the current limit of a power management unit to avoid unwanted automatic interruption of the power flow have been disclosed. The power management unit is automatically adjusted to the output resistance of a power source (including interconnect resistance). The invention maximizes the time and hence the power transferred from a power management unit to the system (including the battery, in case of battery operated systems). The input current is reduced thus increasing the input voltage in case of a high voltage drop across the internal resistance including interconnections between power source and power management unit.

Abstract: A power supply circuit includes a rectifying unit for outputting a rectified input voltage, a transformer for receiving the voltage and outputting an induced voltage based on the input voltage, a first smoothing unit for smoothing the induced voltage to output a first output voltage, a detecting unit for outputting an error signal corresponding to the difference between the first output voltage and a reference voltage, and an insulating unit for receiving the error signal and outputting a signal corresponding to the error signal. The input and output terminals of the insulating unit are insulated. The circuit also includes a controlling unit for outputting a control signal for selectively inputting the input voltage into the transformer on basis of the signal from the insulating unit, and also includes a switching unit connected to the transformer for selectively inputting the input voltage into the transformer, based on the control signal.

Abstract: A method of controlling a multiphase power converter including a plurality of sub-converters coupled to provide power to a load is disclosed. Each sub-converter includes a power switch. The method includes selectively and consistently turning on the power switch of one or more of the sub-converters at substantially a same time as a reference signal representing a desired output of the power converter increases. The method further includes selectively and consistently turning off the power switch of one or more of the sub-converters at substantially a same time as the reference signal representing the desired output of the power converter decreases. Other methods, multiphase power converters and controllers for multiphase power converters are also disclosed.

Abstract: There is provided an optical resonator including: N individual optical waveguide paths of line segment shape disposed in a common flat-plane so as to intersect at a single intersection region, wherein N is an integer of 2 or more; curved optical waveguide paths connecting respective portions of the optical waveguide paths that extend towards the outside from the intersection region, wherein for a first to a 2Nth optical waveguide path portions in a clockwise direction, connection is made between end portions at the opposite side to the intersection region of the (2i?1)th to 2ith optical waveguide path portions, wherein i is an integer of 1 to N; and an optical coupler that couples light input or output perpendicular to the flat-plane with the optical waveguide paths, the optical coupler being formed in a region containing the intersection region where the optical waveguide paths are connected.

Abstract: In a method for controlling a Voltage Source Converter having at least one phase leg comprising a series connection of switching elements, in which each said element has at least two semiconductor devices of turn-off type, at least two free-wheeling diodes connected in parallel therewith and at least one energy storing capacitor, each said switching element is controlled according to a Pulse Width Modulation pattern so that each switching element is switched to change between applying a zero voltage and the voltage across its capacitor across its terminals each time a saw tooth voltage wave for that switching element crosses a reference alternating voltage belonging to that switching element.

Abstract: A method and apparatus for supplying independently switched, regulated power to a plurality of loads is disclosed.

Abstract: A flyback voltage converter includes a transformer having a primary winding and a secondary winding, a switch serially connected to the primary winding for being switched to produce a current in the secondary winding, and a negative lock loop to adjust the peak value of the current in the secondary winding according to a current conduction time during which the current in the secondary winding is higher than a current threshold, such that the peak value of the current in the secondary winding will be in inverse proportion to the time.

Abstract: A DC/DC converter has three half-bridge-type current resonant DC/DC converters that are connected in parallel, have a phase difference of 120 degrees, and are operated at a frequency higher than a resonant frequency. Each of the three half-bridge-type current resonant DC/DC converters includes a transformer having a primary winding, a secondary winding, and a tertiary winding, a series circuit connected to both ends of a DC power source and including first and second switching elements, a series circuit connected to both ends of the first or second switching element and including a resonant reactor, the primary winding of the transformer, and a resonant capacitor, and a rectifying circuit to rectify a voltage generated by the secondary winding and output the rectified voltage to a smoothing capacitor. The tertiary windings are annularly connected to a reactor.

Abstract: A power conditioning unit for delivering power from a power source to a mains utility supply, the power conditioning unit comprising a plurality of input terminals for connecting to the power source, a plurality of output terminals for connecting to the mains utility supply, a voltage increasing converter connected to the input terminals, a voltage reducing converter connected to the voltage increasing converter and a dc-to-ac converter connected to the voltage reducing converter and to the output terminals.

Abstract: A digital device generates a fixed duty cycle signal with an internal oscillator after a Power-On-Reset (POR). This fixed duty cycle signal is output on a signal pin that normally is used for a PWM control signal. The fixed duty cycle signal is used to stimulate the voltage generation circuits so as to power up the digital device for initialization thereof. Once the digital device has powered-up and initialized, the digital device switches over to normal operation for control of the power system.

Abstract: In a power conversion circuit operating with high frequency, an off-voltage control circuit 101u of a lower-arm gate drive circuit 24u controls the output voltage of a gate drive power supply 103u to change the output voltage to a voltage lower than a predetermined off voltage during a time period from termination of turn-off operation of a lower arm 22u until start of turn-on operation of an upper arm 21u, and thereafter return the output voltage to the predetermined off voltage immediately after termination of the turn-on operation of the upper arm 21u. With this control, short-circuiting through the upper and lower arms occurring due to a high voltage change dv/dt can be avoided, and the life of a switching element constituting the power conversion circuit improves, increasing the reliability of the power conversion circuit.

Abstract: A multi-output buck converting apparatus with a controllable energy-releasing function includes a main buck converter and at least one auxiliary buck converter to provide multi-output voltages. The multi-output buck converting apparatus further includes an energy releasing unit and an abnormal voltage signal generating unit. The abnormal voltage signal generating unit generates a control signal to control a switch device of the energy releasing unit when the multi-output buck converting apparatus shuts down. Therefore, the energy, which is stored in the auxiliary buck converter, can be released through the energy releasing unit so as to avoid returning the energy to the main buck converter and rebounding a main output voltage.

Abstract: An object of the present invention is to provide a rectifier circuit which can suppress loss of power due to parasitic capacitance or parasitic inductance of a semiconductor element. The rectifier circuit matches or mismatches impedance between a circuit of a previous stage and the rectifier circuit in accordance with the amplitude of an input AC voltage. When an AC voltage to be input has a smaller amplitude than a predetermined voltage, impedance is matched and the AC voltage is applied as is to the rectifier circuit. Conversely, when an AC voltage to be input has a larger amplitude than a predetermined voltage, impedance is mismatched, and the amplitude of the AC voltage is decreased by reflection and then the AC voltage is applied to the rectifier circuit.

Abstract: An object of the present invention is to generate a reference voltage that is stable in relation to manufacturing process variations, by matching the operating regions of the MOSFETs contributing to generation of the reference voltage.

Abstract: One object of the present invention is to provide a regulator circuit with an improved noise margin. In a regulator circuit including a bias circuit generating a reference voltage on the basis of the potential difference between a first power supply terminal and a second power supply terminal, and a voltage regulator outputting a potential to an output terminal on the basis of a reference potential input from the bias circuit, a bypass capacitor is provided between a power supply terminal and a node to which a gate of a transistor included in the bias circuit is connected.

Abstract: A power control system includes a current sense resistor located on an output side of a switching power converter. By locating the current sense resistor on the output side of the switching power converter, the current sense resistor conducts a sense current when a control switch of the switching power converter is nonconductive. Since a duty cycle of the control switch is larger for a low input voltage than for a higher input voltage, the current sense resistor conducts current for a shorter time duration for low input voltages than for higher input voltages. Thus, the root mean square (RMS) of a sense current in the current sense resistor and, thus, power dissipation by the current sense resistor, is lower during low input voltages than power dissipation in conventionally located current sense resistors. The RMS of the sense current is approximately constant across a full range of input voltages.

Abstract: Method and system for efficient power control with multiple modes. According to an embodiment, the present invention provides a power system with selectable power modes. The power system includes a first terminal for outputting energy, and the first terminal is electrically coupled to a load. The system also includes a pulse-frequency modulation (PFM) component that is configured to adjust a pulse frequency based on the load. The system additionally includes a pulse-width modulation (PWM) component that is configured to adjust a pulse width based on the load. The system further includes a switch that is electrically coupled to the first terminal. Also, the system includes a control component, the control component being configured to provide a control signal that is capable of causing the switch to be turned on or off. The control signal is associated with an output of the PWM component and the pulse width if an output is greater than a predetermined value.

Abstract: A method of power point tracking for operating a photovoltaic power plant, which includes a DC-DC converter of the output voltage of a panel having a power switch driven by a PWM control signal of variable duty-cycle generated by a PWM control circuit, in discontinuous conduction mode or continuous conduction mode depending on the current load of the converter, is implemented by low cost analog circuits. The method does not require the use of any analog-to-digital conversion, digital processing or storage resources and may use a single voltage sensor.