Abstract: A DC-DC converter, adapted to control a converting circuit to convert an input voltage into an output voltage, is disclosed. The converting circuit comprises a switch module and an LC filter, the switch module is coupled to the input voltage, and the LC filter is coupled to the switch module and provides the output voltage. The DC-DC converter comprises a system control circuit, a driver circuit, and an output voltage adjusting circuit. The system control circuit generates a switch control signal according to a reference voltage and a state of the LC filter. The driver circuit controls the switch module according to the switch control signal for adjusting the output voltage in response to the reference voltage. The output voltage adjusting circuit determines whether adjusting the output voltage toward a predetermined adjusting voltage according to an adjusting reference voltage and a detecting voltage indicative of the output voltage.

Abstract: A multi-phase DC-DC controller. The multi-phase DC-DC controller comprises converter channels, a channel control device and a power control device. Each converter channel comprises a switch device, a first output node and an inductor coupled between the switch device and the first output node. The channel control device generates adjusted pulse width modulation signals according to control signals of the converter channels to respectively control operation of the switch device in each converter channel. The power control device generates the control signals according to sensed currents in the converter channels so as to dynamically turn on or off each converter channel according to the sensed currents.

Abstract: A phase current sharing network that adjusts operation of a current mode multiphase switching regulator in which the phase current sharing network includes multiple synthetic ripple networks and a current share network. The regulator develops phase currents including ripple currents through corresponding phase inductors as controlled by corresponding pulse control signals. Each synthetic ripple networks develops a corresponding ripple voltage that simulates a corresponding phase ripple current and uses the ripple voltages to develop the pulse control signals. The current share network adjusts each ripple voltage by a combined adjustment value. The combined adjustment value is a combination of phase adjustment values in which each phase adjustment value is based on a difference between a corresponding one of ripple voltage and a reference voltage. Transconductance amplifiers may be used to convert the voltage differences to current adjust values applied to the ripple capacitors developing the ripple voltages.

Abstract: A sensing circuit senses a load current to generate a sensed signal. A comparator's output is set to a first value if the sensed signal is equal to or greater than a reference signal, and to a second value if the sensed signal is smaller than the reference signal. A one-shot timer generates a logic signal that transitions from a first state to a second state in response to a first occurrence of the first value of the comparator's output, or optionally in response to each subsequent occurrence of the first value of the comparator's output if the one-shot timer is rearmed. A selector sets a first limit for the current delivered to the load in response to the first state of the logic signal, and a second limit for the current delivered to the load in response to the second state of the logic signal.

Abstract: Circuitry and method for providing a signal indicative of instances of conduction of average inductor current in a DC-to-DC voltage converter. Such signal identifies a time when the instantaneous average current being conducted by the inductor in a DC-to-DC voltage converter can be measured by providing a signal edge approximately halfway through one of the increasing and decreasing current conduction intervals of the inductor.

Abstract: This disclosure relates to a voltage converter including a control circuit, a converter sub-circuit, and a single coil, where when the voltage converter can perform bi-directional voltage conversion using the single coil. In other words, the voltage converter can generate one or more regulated output voltages in both directions from one or more input voltages using the same coil.

Abstract: A multi-phase DC-DC controller. The multi-phase DC-DC controller comprises converter channels, a channel control device and a power control device. Each converter channel comprises a switch device, a first output node and an inductor coupled between the switch device and the first output node. The channel control device generates adjusted pulse width modulation signals according to control signals of the converter channels to respectively control operation of the switch device in each converter channel. The power control device generates the control signals according to sensed currents in the converter channels so as to dynamically turn on or off each converter channel according to the sensed currents.

Abstract: A ground return path is determined to be impaired when no zero-sequence current is measured in the neutral return path, but zero-sequence current is detected in other suitable measuring points that include the windings of an autotransformer, or in a magnetically coupled delta-configured tertiary winding, or potential transformer.

Abstract: A high voltage/power semiconductor device has a substrate, an insulating layer on the substrate, and a semiconductor layer on the insulating layer. Low and high voltage terminals are connected to the semiconductor layer. The device has a control terminal. The semiconductor layer includes a drift region and a relatively highly doped injector region between the drift region and the high voltage terminal. The device has a relatively highly doped region in electrical contact with the highly doped injector region and the high voltage terminal and forming a semiconductor junction with the substrate. The combination of the insulating layer and the relatively highly doped region of the first conductivity type effectively isolate the highly doped injector region from the substrate.

Abstract: A modulated power supply comprises a power switching stage having at least one power switching device for generating a power signal in response to an input modulating signal. A current source is positioned in parallel with the power switching stage and continuously generates an output current. An output stage combines the power signal and the output current to form an output power supply signal. The current source supplies some, or all, of the required current at any given time. The switching device in the power switching stage either supplies the remaining required current or sinks any excess current. This has an advantage of reducing the average and peak currents flowing through the switching device, and hence the average power dissipation in the device. The output current can be set at an average (e.g. RMS) value of the current in the output power supply signal.

Abstract: An active power factor correction (PFC) circuit and its controlling method are provided. The method comprises the following steps. Drive the power switch of the circuit so that the average inductor current waveform follows the rectified input voltage waveform. Suspend the operation of the power switch at a first moment in a first line cycle of the rectified input voltage and then resume the operation of the power switch at a second moment in a second line cycle of the rectified input voltage. The first moment is when the phase angle of the rectified input voltage exceeds a predetermined angle and the switching frequency of the power switch exceeds a predetermined frequency. The time span from the first moment to the end of the first line cycle is substantially as long as the time span from the beginning of the second line cycle to the second moment.

Abstract: Apparatus operates at a power level within a range of power levels that includes a rated maximum power level of the apparatus. The apparatus includes circuit elements to deliver power at an output voltage to a load from a source at an input voltage using an inductor selectively connected between the source and the load during a power conversion cycle. The inductor conducts a current having an average positive value during the power conversion cycle. A first switching device is interposed between the source and a first terminal of the inductor. A second switching device is interposed between a second terminal of the inductor and the load. A switch controller turns ON the first switching device during a time interval within the power conversion cycle during which the current is negative.

Abstract: A pulse width modulator (305) for driving a load in a multi-phased power system having circuitry (270) responsive to channel signals for providing an average signal by summing the channel signals at a node (221) which is coupled with a plurality of resistive elements, and having further circuitry for providing an error between said load and said reference potential, and having still further circuitry (250) for summing the channel signals, average signal, and error for providing a respective drive signal for each of the power switches, wherein the error signal and the average signal have complementary effects on a duty factor of the drive signals and the channel signal has an effect contrary to the error signal and the average signal. Further, a plurality of pulse width modulators (305) can be combined as a system (300) by connecting respective nodes (221) for providing current sharing between all phases.

Abstract: A circuit for controlling power to a capacitive load includes a DC power source coupled in series with an inductor and the capacitive load. The inductor provides for resonant charging of the capacitive load from the DC source. A second inductor is used for resonantly discharging the capacitive load back to the power source. Solid state switches are included for selectively activating the charging and discharging of the capacitive load. An energy absorbing load is selectively coupled across the capacitive load to remove any residual voltage after a discharging process.

Abstract: Using a switching circuit (2) for a reactive power compensation device (1), he compensation capacitors of the reactive power compensation device (1) can be switched on with voltage measuring devices (30, 31) which are switched between two phase conductors (3, 4) if the the voltage is the same on both sides of an open phase conductor switch (24). In a preferred embodiment, closing the second phase conductor switch (25) occurs triggered by a delay device (36) following a fixed delay time. In another preferred embodiment, switching on occurs when the voltage is the same between the phase conductors (4,5) on both sides of the second phase conductor switch (25), whereas this condition can be checked with two other voltage measuring devices switched between the phase conductors (4, 5) as well as with another equivalence comparator.

Abstract: A method and apparatus for protecting switching elements, and in particular, thyristor switching elements, which are used to supply pulses to a capacitive load, from damage resulting from false triggering signals, i.e., triggering signals not accompanied by actual sparkover conditions in the load. Since termination of normal pulse cycles in such pulser systems are accomplished by a return to high forward voltage across the switching elements, false triggers generated closely prior to such termination and within the forward recovery time of a thyristor switching element present a danger that the termination of a normal cycle will result in a weak turn-on and consequent damage of the switching element. By insuring that all such potentially false triggers have a duration which extends past termination of the pulse cycle damage to the switching element resulting from such false triggers is inhibited.

Abstract: A method and apparatus for protecting switching elements, and in particular, thyristor switching elements, which are used to supply pulses to a capacitive load, from damage resulting from sparkover occurring in that load are described. The load voltage pulse is characterized by a period of rising voltage followed by a period of falling voltage, these two periods being separated by a transition period of maximum vulnerability of the switching element to damage from sparkover. Specifically, during this period of maximum vulnerability of the switching elments to damage, a gate trigger pulse is applied to the elements to cause them to resume a conductive state, independent of the occurrence of an abnormal sparkover condition.

Abstract: Voltage and current supplied to the primary winding of the transformer-rectifier (T-R) set of an electrostatic precipitator via silicon-controlled rectifiers and a reactor are automatically controlled by sensing spit and spark discharges within the precipitator and the phase shift which occurs between line voltage and line current (usually referred to herein as primary current) when precipitator voltage drops to a low value, as caused by a heavy spark or arc. Signals are developed therefrom which are used to control precipitator voltage through phase control of the SCR's. An arc is extinguished at the end of the current one-half cycle in which it starts. An inhibit circuit is provided for preventing detectable transients caused by SCR turn on from falsely triggering the automatic control system thereby permitting increased sensitivity in the spit sensing circuit.