Abstract: A switching-mode power supply (SMPS) for an image forming apparatus which may prevent an overvoltage supplied to the SMPS, and damage to circuits in the SMPS in the image forming apparatus. The SMPS includes a rectifying circuit to rectify an alternating-current (AC) voltage input from an external power supply source into a direct-current (DC) voltage, a transformer to transform the rectified DC voltage input to a primary coil and output the transformed DC voltage to a secondary coil, a main switch that is connected to the primary coil and switches an output of the transformer, a first overvoltage detecting unit to determine whether the rectified DC voltage is an overvoltage by comparing the rectified DC voltage with a first reference voltage, and a switching control unit to control a switching operation of the main switch based on a result of the determination.

Abstract: A power converting apparatus makes reduction of power loss possible and operates in a two-phase mode. A power converting apparatus of the inventive concept includes I-shaped block cores, each being made of a magnetic material; and E-shaped cores, each being produced by combining two L-shaped magnetic materials to each of the I-shaped cores. In each of the E-shaped cores, the block core is defined as a central leg, the other two legs are defined as a first outside leg and a second outside leg, respectively, and a closed magnetic path is configured by two E-shaped cores combined such that one of respective central legs in the two E-shaped cores, one of respective first outside legs therein, and one of respective second outside legs therein are caused to face the other of the central legs, the other of the first outside legs, and the other of the second outside legs.

Abstract: A method and a control device control a switching device for providing a resonant circuit with a switching voltage for generating a resonant current in order to provide a required output power at an output of a resonant power converter.

Abstract: A power supply for converting AC to a regulated DC output current, utilizing two serial switched mode power supplies, the first providing an intermediate DC output voltage with only moderate ripple properties, this output being input to the second, which operates as a DC/DC converter to provide the desired output with low ripple and good regulation. The diode rectifier assembly has no reservoir/smoothing capacitor, or one of much smaller capacitance than in prior art power supplies. The large resulting rectifier output ripple is overcome by use of the two power supply units, at least the first having a smoothing capacitor at its output. A majority of the energy stored in this capacitor is utilized during each AC half cycle. Such power supplies also provide improved hold-up times. The power supply is also constructed to have low standby power consumption, by use of a double burst configuration.

Abstract: An inverter control circuit (6) controls the operation of a plurality of switching elements in a three-phase inverter circuit (2) by a PWM signal. A phase voltage output from the three-phase inverter circuit (2) is outputted through a low-pass filter (3). A waveform of the phase voltage output from the low-pass filter (3) assumes the following waveforms through the control of the PWM signal. The waveform becomes zero in a first one-third period of a cycle; forms a sine wave corresponding to a phase from 0 to 2?/3 in a second one-third period; and forms a sine wave corresponding to a phase from ?/3 to ? in a remaining one-third period of the cycle. Such PWM signal cyclically includes a period where a pulse is not generated. Therefore, the switching action of the switching element is periodically stopped.

Abstract: The present invention provides a series of DC-DC converter circuit designs, and DC-DC converters based on such circuit design, that provide high input-to-output voltage conversion. The converters include a resonant tank and a means for interrupting the tank current to produce a near zero-loss “hold” state wherein zero current and/or zero voltage switching is provided, while providing control over the amount of power transfer. A resonant DC-DC converter for high voltage step-up ratio in accordance with the circuit design includes: (a) a low voltage DC-AC converter, (b) a resonant tank, (c) a high voltage AC-DC converter, (d) a (i) common ground on an input and an output without use of a transformer and/or (ii) a single high voltage controllable switch within the resonant tank.

Abstract: A controller of a switching power converter employs a dynamically adaptive power supply regulation approach that improves low-load and no-load regulation to achieve ultra-low standby power in a switching power converter. Under ultra-low load conditions when a deep-deep pulse width modulation (DDPWM) is applied, the controller decreases the actual on-time of the power switch of the switching power converter by decreasing the “on” duration of the control signal used to turn on or off the power switch, until the “on” duration of the control signal reaches a minimum value. To further reduce the on-time of the power switch, the controller reduces the power applied to the power switch to turn on the switch more slowly, while maintaining the “on” duration of the control signal at a minimum value. The minimum value of the “on” duration of the control signal and the minimum power applied to the switch are dynamically controlled.

Abstract: A series resonant converter of the present invention includes an inverter circuit having at least a pair of a first and second switching device connected between two input terminals, a transformer having a primary winding and a secondary winding connected to the inverter circuit, a first and second resonant capacitor connected to a secondary side of the transformer and connected in series to each other between two output terminals, a first and second unidirectional device connected in series to each other, and a resonant induction device that is operated along with the first and second resonant capacitor and resonates in series. The first and second unidirectional device are configured such that current does not flow from the first and second resonant capacitor to the input terminal by preventing electric charge of the first and second resonant capacitor from being discharged to a primary side of the transformer.

Abstract: A system and method for extracting power from a power source having a high internal resistance are presented. A capacitor is connected to the power source. A switch is configured to selectively connect and disconnect the capacitor from a load. A processor is configured to monitor an energy flow from the power source into the capacitor and an amount of energy in the capacitor. When the energy flow from the power source into the capacitor falls below a first threshold, the processor is configured to close the switch to dissipate energy from the capacitor to the load. When the energy in the capacitor falls below a second threshold, the processor is configured to open the switch to disconnect the capacitor from the load.

Abstract: A power supply produces one or more conditioned and scaled output voltages with low noise. The power supply has various components to produce a plurality of higher output voltages from a plurality of taps of a multiplier or multiple isolated outputs. Components include an internal reference voltage circuit or an external voltage that generates a reference voltage and a sine wave power oscillator circuit and resonant circuit that generates an alternating current and voltage. The power supply has a controlled current source circuit connected to the sine wave power oscillator circuit for regulating the power level to the sine wave power oscillator. A control amplifier circuit controls the current level to the controlled current source circuit based on the error between the sampled output and the reference voltage. The resonant transform connected to the sine wave power oscillator circuit generates one or more scaled output voltages on one or more secondary windings.

Abstract: To provide an electrical junction box that can maintain a stable assembly condition between a box main body and a cover member, even if locking mechanisms are not provided on a whole periphery of the electrical junction box. An electrical junction box includes a box main body and a cover member. One of the box main body and the cover member is provided on at least a single of side portions of the one peripheral wall with a locking mechanism. An elastic rib that protrudes from an inner peripheral surface of the one peripheral wall at one of the side portions is pressed onto a fitting projection piece. A side portion is provided with a support wall that is opposed to and spaced apart from the inner peripheral surface. The fitting projection piece is held in a space between the inner peripheral surface and the support wall.

Abstract: A switching power supply apparatus includes a low-side switching control unit and a high-side switching control unit. The low-side switching control unit includes a low-side turn-off circuit that turns off a low-side switching element behind a delay time when reversal of the polarity of a winding voltage of a transformer is detected during a period in which a drive voltage signal is supplied to the low-side switching element. The high-side switching control unit includes a high-side turn-on delay circuit that delays a time from the time when the polarity of the winding voltage of the transformer is reversed to a time when a high-side switching element is turned on. The delay time of the low-side turn-off delay circuit is set so as to be shorter than the delay time of the high-side turn-on delay circuit.

Abstract: Provided are a coil component capable of contributing to improving productivity of a reactor, and a reactor exhibiting good productivity. A reactor 1A includes one coil 2 formed by spirally winding a wire 2w, and a magnetic core 3, which is disposed inside and outside the coil 2 and which forms a closed magnetic circuit. The magnetic core 3 includes an inner core portion 31 disposed inside the coil 2, and an outer core portion 32 disposed around the coil 2. The coil 2 and the inner core portion 31 constitute a coil component 2A held as an integral unit by a resin molded portion 20. A shape of the coil 2 is maintained by the resin molded portion 20. Since the coil component 2A includes a portion of the magnetic core 3, the number of components can be reduced, and the coil 2 and the inner core portion 31 can be easily placed into a case 4A when they are housed therein. The coil 2 is easier to handle because the coil shape is constantly maintained without expanding or contracting.

Abstract: Driver circuits (1) for driving load circuits comprise transformer circuits (21) with primary side windings to be coupled to source circuits and with secondary side windings to be coupled to the load circuits. By providing the driver circuits (1) with determination circuits (22) for determining secondary side currents as functions of primary side currents, primary side voltages, primary side inductances and transformer ratios, the secondary side currents can be determined solely at primary sides of the transformer circuits (21). Functions may define secondary side currents to be proportional to differences between first signals proportional to integrals of primary side voltages divided by primary side inductances and second signals proportional to primary side currents, the differences being multiplied by the transformer ratios.

Abstract: A switched mode power converter controller outputs a switch control signal for a switch, receives sensed voltage and primary current input signals, and includes a constant current mode controller to process voltage input signals and generate output control signals for controlling converter peak current and/or switching frequency operational; a constant voltage mode controller processes the voltage input signal and generates output control signals for converter peak current and/or switching frequency operational parameters; a primary peak current adjuster processes primary current input and output control signals from the current and voltage mode controllers to configure the switch control signal to turn off the switch; a switching frequency adjuster processes output control signals from the current and voltage controllers to configure the switch control signal to turn on the switch.

Abstract: A DC-DC converter includes a plurality of switch elements connected in series between both ends of a DC power source, a series circuit of a primary winding of a transformer and a capacitor, connected between a connection point of the plurality of switch elements and an end of the DC power source, a rectifying-smoothing circuit to rectify and smooth a voltage generated by a secondary winding of the transformer into a DC voltage, and a controller to change a switching frequency of the plurality of switch elements according to a feedback signal generated from the DC voltage and alternately turn on/off the plurality of switch elements. The controller includes a nonlinear response unit 11a to nonlinearly change the switching frequency according to a feedback amount represented by the feedback signal.

Abstract: A power supply can provide brown-out protection and overheat protection. The power supply includes a rectifier, a transformer, and a power management device. The rectifier is used for receiving an alternating current voltage. The alternating current voltage has a voltage cycle. The transformer coupled to the rectifier has an inductor coupled to a switch for supplying an output voltage. The power management device is used for controlling the switch to make the inductor save power or release power. The power management device has a multi-functional pin coupled to the rectifier for receiving a detection voltage corresponding to a positive half cycle of the alternating current voltage. The multi-functional pin is also coupled to a thermistor for receiving an overheat protection signal.

Abstract: A power supply device including a rectifying unit, a supplying unit, a controlling unit, a conversion unit and a detection unit is disclosed. The rectifying unit processes an alternating current (AC) voltage to generate a direct current (DC) voltage. The supplying unit generates an operation voltage according to an input voltage. The controlling unit receives the operation voltage and generating an enabling signal. The conversion unit transforms the DC voltage to generate an auxiliary voltage according to the enabling signal. The auxiliary voltage is not equal to the operation voltage. The detection unit detects the auxiliary voltage. When the auxiliary voltage is generated, the detection unit de-activates the supplying unit to stop generating the operation voltage.

Abstract: An integrated switching power supply device includes a series-connected body, a driving control element, and external terminals. In the series-connected body, a switching element, a constant current element, and a diode are connected in series. The driving control element controls to drive the constant current element. The external terminals include first to seventh external terminals. The first and second external terminals are connected to main terminals of elements of the series-connected body. The third external terminal is connected to a connection point of main terminals of the switching element or the constant current element and a main terminal of the diode. The fourth external terminal is connected to a control terminal of the switching element. The fifth external terminal supplies electric power to the driving control element. The sixth external terminal inputs reference potential. The seventh external terminal inputs a signal to the driving control element.

Abstract: An apparatus and a method for converting power from a power input to an DC output voltage or current, which apparatus has a serial resonance converter, where a first feedback circuit is connected from the output terminal to an error amplifier, where the apparatus further has a second feedback circuit with at least one first resistor that is connected to a coil and to ground, which second feed back circuit connects the line between the first resistor and the coil and towards an inverting integrator, the output of which is connected through a second capacitor to a second input at a control circuit. As a result, the oscillating frequency is under influence of a signal that depends on the voltage generated in the resistor connected in serial to the coil or transformer.

Abstract: A DC-DC converter is configured with a voltage-source power converter provided at a primary side of a transformer, a current-source power converter provided at a secondary side of the transformer, and a controller. The controller generates a first control input based on a voltage between input and output terminals of the voltage-source power converter, a second control input based on a voltage between input and output terminals of the current-source power converter, and a command value for PWM or PFM control based on the first and second control inputs and an input-output current flowing between one of the input and output terminals of the voltage-source power converter and the current-source power converter. Therefore, it is easy to switch between a powering state and a regenerating state in the DC-DC converter.

Abstract: An example power supply controller includes a signal separator circuit that generates a feedback signal. An error signal generator generates an error signal in response to the feedback signal. A control circuit generates a drive signal in response to the error signal. The drive signal controls switching of a switch. A multi-cycle modulation circuit is included in the control circuit and generates a skip signal in response to a start skip signal, a stop skip signal and a skip mask signal. The skip mask signal is generated in response to the skip signal. The start skip and stop skip signals cause the drive signal to start skipping or stop skipping, respectively, on-time intervals of cycles. The skip mask signal disables the start skip signal from causing the drive signal to start skipping the on-time intervals of cycles.

Abstract: A power conversion circuit converting DC electric power into AC electric power and sending the AC power to an inductive load, includes a first switching device connected to the positive pole side of the DC power supply to exhibit a conductive state and an interrupted state of a current; a second switching device connected to the negative pole side of the DC power supply to exhibit a conductive state and an interrupted state of the current; a first inductor provided between the first switching device and the inductive load; a second inductor provided between the second switching device and the inductive load; and a clamping diode connected between a first connection point between the first switching device and the first inductor, and a second connection point between the second switching device and the second inductor. Thus, conduction is provided from the second connection point to the first connection point.

Abstract: We describe a power conditioning unit with maximum power point tracking (MPPT) for a dc power source, in particular a photovoltaic panel. A power injection control block has a sense input coupled to an energy storage capacitor on a dc link and controls a dc-to-ac converter to control the injected mains power. The power injection control block tracks the maximum power point by measuring a signal on the dc link which depends on the power drawn from the dc power source, and thus there is no need to measure the dc voltage and current from the dc source. In embodiments the signal is a ripple voltage level and the power injection control block controls an amplitude of an ac current output such that an amount of power transferred to the grid mains is dependent on an amplitude of a sinusoidal voltage component on the energy storage capacitor.

Abstract: A converter includes an active stage for converting an AC input voltage at an AC input into an intermediate DC voltage, and a DC/DC converter for transforming the intermediate DC voltage into an output DC voltage at a DC output. The DC/DC converter has a resonant transformer formed by a resonant circuit and a transformer. The converter also includes control unit configured to actively operate the active stage only based on an output DC voltage of the DC/DC converter, an input voltage, and an input current of the converter, and to operate the DC/DC converter in an open loop mode. A method for operating such a converter is also provided.

Abstract: A power conversion apparatus includes a high-power-factor converter section converting an AC voltage to a DC voltage, a smoothing capacitor, a DC/DC converter section, and a control circuit. The control circuit controls the high-power-factor converter section such that the power factor of AC is controlled and a DC voltage follows a target value, and performs duty control for semiconductor switching devices such that a DC voltage from the DC/DC converter section to a load follows an instruction value. In accordance with the DC voltage, the control circuit adjusts the DC voltage target value of the high-power-factor converter section such that the duty ratio of the semiconductor switching devices approaches a set value, thereby optimizing the duty ratio of the semiconductor switching devices and reducing power loss.

Abstract: Among many embodiments, a power conversion apparatus and a method for converting power are disclosed. The power conversion apparatus may include switching components configured to create an alternating current; a preemptive detector arranged and configured to provide, in advance of the alternating current reaching a zero-crossing, a control signal responsive to the alternating electrical current approaching the zero-crossing; and a controller configured, at least in part, to change a state of the switching components before the zero crossing, in response to the control signal.

Abstract: A DC-DC converter having a first and a second switch, an input diode, a magnetizing inductor, a resonant capacitor, a resonant inductor, an output diode and an output filter capacitor. The first and second switches are turned on alternatively. When the first switch is turned on, an input voltage is coupled to an anode of the input diode that has a cathode coupled to a first terminal of the magnetizing inductor. The second switch is designed to short a second terminal of the magnetizing inductor to a ground. The resonant capacitor and inductor, which are coupled in series, are disposed between the second terminal of the magnetizing inductor and the ground. A connection node between the resonant capacitor and inductor is coupled to the output filter capacitor, via the output diode, to regulate a voltage of the output filter capacitor. The regulated voltage is used in powering a load.

Abstract: A resonant dc-dc converter converts dc input voltage to a dc output voltage. The converter includes switching, switching driving, conversion, and disabling circuits. The switching circuit receives the input voltage and generates a square wave voltage oscillating between the input voltage and a low value, at a frequency with a duty cycle. The switching driving circuit drives the switching circuit and includes a timing circuit for setting the frequency and the duty cycle. The timing circuit sets the value of the duty cycle to about 50% when the converter operates in steady state. The conversion circuit generates the output voltage from the square wave voltage based on the frequency and the duty cycle. The disabling circuit temporarily halts the timing circuit after a power on in such a way to temporarily vary the duty cycle of the square wave voltage during a period of the square wave voltage.

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 converter device comprising a power supply input, rectifier means, switching means, control means, and a switching aid circuit, said switching aid circuit comprising inductive means, branch-off means of an input current, and power storage means. The device of the invention is characterized in that the inductive means are essentially formed by a transformer directly connected to the power supply input and comprising reverse-coiled windings, and that the branch-off means comprise auxiliary switching means directly connected between said inductive means and a voltage reference or an output line to establish branch-off of the input current onto said inductive means before main turn-on. An uninterruptible power supply comprising the converter device described above.

Abstract: A high-voltage power-supply apparatus comprises a controller configured to output a control signal containing a pulse with a variable drive frequency; a switching unit configured to be switched by the control signal and output a drive signal; a piezoelectric transducer having a predetermined resonant frequency, and configured to be driven by the drive signal and output a high-voltage output voltage; a current detector configured to detect an electric current of a load connected to an output side of the piezoelectric transducer and output a current-detection result; and a lower-limit-value setup unit configured to set a frequency lower limit value for the drive frequency of the controller. The controller is configured to vary the frequency lower limit value in accordance with the current-detection result.

Abstract: The present invention relates to voltage transformers, comprising multi-layer structures of piezoelectric ceramics, so-called piezoelectric transformers. The present invention further relates to switched mode power supplies, comprising such a piezoelectric transformer as part of a piezoelectric converter. The piezoelectric transformer according to the invention comprises a primary-side electrode arrangement (102) that can be connected to the primary-side voltage, a secondary-side electrode arrangement (104) on which the secondary-side voltage can be tapped, and an auxiliary electrode arrangement (106) for creating an auxiliary electrode voltage proportional to the secondary-side voltage, wherein the auxiliary electrode arrangement (106) is formed by at least two plane electrodes located opposite one another.

Abstract: An LCD backlight driving device with an isolating transformer comprises a DC power supply, a square wave generator, a square wave controller, said isolating transformer and a driver transformer; wherein said isolating transformer has a primary side connected to said square wave generator and a secondary side connected to said driver transformer, since said isolating transformer is placed between said square wave generator and said driver transformer, it helps to effectively shorten a safety distance required for setting up said driver transformer; the present invention uses said isolating transformer to shorten the safety distance required than that of using said driver transformer directly and to decrease an area in implementing a circuit board and to cut cost of said device.

Abstract: Disclosed herein is a method of controlling the current of a high-speed Switched Reluctance Motor (SRM) using an inverter circuit including a first switching element, a second switching element, a first diode, a second diode and a reactor, wherein the first switching element and the first diode, the second diode and the second switching element are connected to a bridge circuit, and one end of the reactor is connected to the junction of the first switching element and the first diode, and the remaining end of the reactor is connected to the junction of the second diode and the second switching element; and excitation mode, free-wheeling mode-1, the excitation mode, and free-wheeling mode-2 are sequentially performed in a unit period T, and, when the control is terminated, demagnetization is performed.

Abstract: Disclosed herein are systems and methods for converting data samples representing alternating electric currents. The data samples may be obtained by sampling a first alternating electric current having a first frequency at a sampling frequency, sampling a second alternating electric current having a second frequency at the sampling frequency, and converting the data samples using a conversion algorithm to compensate for any discrepancy caused by the difference between the first frequency and the second frequency. The corrected data samples may be utilized to determine various characteristics of the alternating electric current, such as voltage magnitude, voltage phase angle, current magnitude, current phase angle, and other related attributes. In one application, the systems and methods disclosed herein may be utilized in connection with an intelligent electronic device used to couple a first electrical system, such as a power generator, to a second electrical system, such as a utility intertie.

Abstract: A power supply circuit for receiving an input voltage to drive a plurality of loads is disclosed. The power supply circuit comprises a plurality of switch circuits, a plurality of power conversion circuits and a phase delay circuit. The plurality of switch circuits are connected with the plurality of loads, respectively. The plurality of power conversion circuits are connected with the plurality of loads and the plurality of switch circuits, respectively, for converting the input voltage into a plurality of driving voltages and transmitting the plurality of driving voltages to the plurality of loads, respectively, when the plurality of switch circuits are conducted.

Abstract: Disclosed are advances in the arts with novel and useful current mode regulators. Circuits, systems, and methods for current mode regulation include a primary side for receiving an input signal and a secondary for outputting an output signal. A regulator spans the primary and secondary sides in a configuration by which the input signal may be rectified and thereafter provided to the output node as an output signal. A current monitor is provided at the output node for comparing the output signal to a reference. A communication link is included for providing feedback to the primary side of the regulator for use in regulating the signal.

Abstract: A resonant power converting circuit is provided, which includes a resonant converting unit, a control unit, a voltage detecting unit and a frequency modulation unit. The control unit outputs switching signals to the resonant converting unit to adjust an output of the resonant converting unit. The voltage detecting unit is configured to detect an output voltage of the resonant converting unit. The frequency modulation unit may adjust a lowest switching frequency of the control unit according to the detected output voltage so as to increase a gain of the resonant converting unit and an output stability of the resonant converting unit.

Abstract: A power system includes a plurality of DC/DC converters and a DC/AC inverter. The plurality of DC/DC converters having outputs electrically connected in parallel for supplying a DC voltage bus to an input of the DC/AC inverter. The plurality of DC/DC converters each include a maximum power point tracker (MPPT). Various DC/DC converters and DC/AC inverters suitable for use in this system and others are also disclosed.

Abstract: A freewheeling MOSFET is connected in parallel with the inductor in a switched DC/DC converter. When the freewheeling MOSFET is turned on during the switching operation of the converter, while the low-side and energy transfer MOSFETs are turned off, the inductor current circulates or “freewheels” through the freewheeling MOSFET. The frequency of the converter is thereby made independent of the lengths of the magnetizing and energy transfer stages, allowing far greater flexibility in operating and converter and overcoming numerous problems associated with conventional DC/DC converters. In one embodiment the freewheeling MOSFET is an N-channel MOSFET with its body connected to circuit ground and not shorted to either its source or its drain.

Abstract: This printed circuit board (12) comprising: a first portion (20) having first electronic components (22) of which the earth electrode is on a first voltage source (14); a second portion (24) having second electronic components (26) of which the earth electrode is on a second voltage source (16); a third portion (28) inserted between the first portion (20) and the second portion (24); a switched-mode power supply circuit (32) connecting the first portion (20) and the second portion (24); the said second portion (24) also comprising an electronic component (30) powered by the said first voltage source (14), is characterized in that it also comprises detection means (34) for detecting a drop in electrical consumption of the component (30) and switching means for switching the switched-mode power supply circuit (32) when a predetermined drop in electrical consumption of the said component (30) is detected.

Abstract: A DC-DC converter, which is configured to step down a direct current voltage and then outputs to a load, the DC-DC converter comprising: a switching device that converts the direct current voltage into an alternating current voltage; a rectification unit that rectifies the alternating current voltage; an output capacitor that is connected in parallel with the load, and a smoothing inductor comprising a plurality of divided inductors connected in series, wherein at least one of the number of windings and the number of layers of respective windings of the divided inductors of the smoothing inductor is adjusted so that a sum total of inductances of the divided inductors become a desired inductance and so that a sum total of floating capacitances of the plurality of the divided inductors is smaller than a floating capacitance of single inductor having an equivalent inductance.

Abstract: A first rectifier diode is electrically connected between a first input terminal where an alternating current (AC) power is received and a first output terminal where a direct current (DC) power is output. A second rectifier diode is electrically connected between the first input terminal and a second output terminal. The first and second rectifier diodes rectify first and second portions of the AC power into the DC power, respectively. When switching of a plurality of power factor correction (PFC) switches is enabled, the plurality of PFC switches increases a voltage of the DC power to greater than a peak voltage of the AC power. An inductor is electrically connected between a second input terminal and two of the plurality of PFC switches. When the switching is disabled, first and second bypass diodes provide a current path past the plurality of PFC switches and the inductor.

Abstract: The present invention includes: a power factor correction circuit configured to correct a power factor; a DC/DC converter configured to convert an output voltage of the power factor correction circuit to a different direct-current voltage; an input voltage detector configured to detect an input voltage inputted into the power factor correction circuit; and a power factor correction circuit output voltage controller configured to generate a voltage instruction for controlling the output voltage of the power factor correction circuit, based on a value of the detected input voltage, an output current value to a load connected to an output of the DC/DC converter or an output power value of the load, as well as a set value of an input voltage short break output hold time, and to output the voltage instruction to the power factor correction circuit.

Abstract: In a controller for a power converter, a control terminal can provide a control signal to control a power converter. A cycle of the control signal includes a first time interval and a second time interval. The control circuitry can increase a primary current flowing through a primary winding of transformer circuitry and a secondary current flowing through a secondary winding of the transformer circuitry in the first time interval, and can terminate the increasing of the primary current in the second time interval. The control circuitry can also control the first time interval to be inversely proportional to an input voltage provided to the primary winding.

Abstract: An adaptive inductive ballast is provided with the capability to communicate with a remote device powered by the ballast. To improve the operation of the ballast, the ballast changes its operating characteristics based upon information received from the remote device. Further, the ballast may provide a path for the remote device to communicate with device other than the adaptive inductive ballast.

Abstract: A D/A converter having reference node for receiving a reference voltage and together network having a network reference bus connected to the reference node by way of a first electrical connection. The converter network produces a series of reference outputs derived from the reference voltage in response to a digital input applied to the converter, with the converter network sinking a network reference current at the network reference bus which varies with the converter digital input. A reference current compensator circuit is included which provides a compensation current at the network reference bus having a magnitude which varies in response to at least a portion of the digital input, with the compensation current operating to reduce variations in current through the first electrical connection caused by changes in the digital input.

Abstract: An adaptive inductive ballast is provided with the capability to communicate with a remote device powered by the ballast. To improve the operation of the ballast, the ballast changes its operating characteristics based upon information received from the remote device. Further, the ballast may provide a path for the remote device to communicate with device other than the adaptive inductive ballast.

Abstract: The configurations of a DC/DC resonant converter and a controlling method thereof are provided. The proposed converter includes an over-current protection apparatus including a first switch element having a first and a second terminals, and a first voltage element having a negative terminal coupled to a positive terminal of a DC input voltage source and a positive terminal coupled to the second terminal of the first switch element.