Abstract: An AC-DC power converter has a phase-shifting autotransformer based rectifiers and DC capacitors. Soft start of the AC-DC power converter is achieved by designing the autotransformer to operate at a low peak flux density at a point of AC voltage step application (initial turn on). The addition of a controlled impedance segregates capacitor charging from the initial magnetizing process of the autotransformer.

Abstract: A power supply system and method includes a switch state controller that is operational to control a switching power converter during certain power loss conditions that cause conventional switch state controllers to have diminished or no functionality. In at least one embodiment, during certain power loss conditions, such as when an auxiliary power supply is in standby mode or when the switching power converter is not operating, a power supply for the switch state controller does not provide sufficient operating power to the switch state controller during certain power loss conditions. In at least one embodiment, during such power loss conditions power is generated for the switch state controller using sense input and/or sense output currents of the switching power converter to allow an integrated circuit (IC) switch state controller to generate a control signal to control a switch of the switching power converter.

Abstract: A method is provided for determining a control scheme for a voltage source converter (VSC) with a topology of three bridge legs between each of three phases of a grid and a neutral point. The method includes: analyzing the waveform of the grid and/or a load voltage and determining an allowed period for no-swilching of the corresponding bridge leg; operating the VSC with different clamping carrier modulator frequencies, and then analyzing the balance in the operating junction temperatures and/or power losses across the active switches and also analyzing the total losses of the VSC; comparing the balance and the total losses of different clamping carrier modulator frequencies and selecting the clamping carrier modulator frequency; operating the VSC with the selected clamping carrier modulator frequency, and optimizing the balance in the operating junction temperatures and/or power losses across the active switches and the total losses of the VSC.

Abstract: A flyback converter uses primary side sensing to sense the output voltage for regulation feedback. Such sensing requires a predetermined minimum duty cycle even with very light load currents. Therefore, such a minimum duty cycle may create an over-voltage condition. In the flyback phase, after a minimum duty cycle of the power switch at light load currents, a synchronous rectifier turns off approximately when the current through the secondary winding falls to zero to create a discontinuous mode. If it is detected that there is an over-voltage, the synchronous rectifier is turned on for a brief interval to draw a reverse current through the secondary winding. When the synchronous rectifier shuts off, a current flows through the primary winding via a drain-body diode while the power switch is off. Therefore, excess power is transferred from the secondary side to the power source to reduce the over-voltage so is not wasted.

Abstract: A power converter and a method of operation thereof is disclosed including an input, an output, a sensor unit, a switched power converter, and a processor module. The power converter may convert an input power into an output power. The power converter may sense real-time measurements of the input power and the output power to determine a real-time calculated efficiency. The power converter may chop the input power into sized and positioned portions of the input power based on a plurality of determined operating parameters. The power converter may determine the operating parameters based on the real-time calculated efficiency and on a plurality of other operating factors/conditions.

Abstract: A switch control circuit for controlling a first switch element and a second switch element within a bridgeless switching circuit is provided. The bridgeless switching circuit generates an output signal according to an alternating current signal. The switch control circuit includes a current generating element and a phase generating element. The current generating element is for sensing a first current flowing through the first switch element and a second current flowing through the second switch element, and generating a phase comparison result according to the first and the second currents. The phase generating element generates a first control signal and a second control signal according to a power factor correction signal and the phase comparison result to control conducting status of the first and the second switch elements, respectively.

Abstract: A method of controlling a power factor correction (PFC) converter that has a discontinuous input current includes sensing the input current, sensing an output voltage and controlling a duty cycle of at least one switch in the converter in response to the sensed input current and output voltage using a control equation for controlling the duty cycle of the switch such that an average input current to the converter is sinusoidal. Example circuits capable of performing the method are also disclosed.

Abstract: A power supply circuit to detect whether or not abnormal current is generated in a power factor compensation circuit and forcibly stop an operation of an interleaved power factor compensation circuit controller if abnormal current is generated. The power supply circuit includes a rectifier, a power factor compensation circuit including a plurality of reactors, a plurality of switches and a plurality of current detectors, a power factor compensation circuit controller to control switching of the switches and to control a power factor compensation operation, and a power factor compensation circuit protection circuit to receive the voltages output from the plurality of current detectors and to stop the operation of the power factor compensation circuit controller if at least one of the voltages output from the plurality of current detectors is abnormal. Thus, it is possible to prevent failure of the switches and the current detectors due to abnormal current.

Abstract: Proposed are a power factor correction device and its control method capable of obtaining a stable output as the output of a power supply unit while simplifying and miniaturizing the configuration. In the power factor correction device and the control method thereof including a coil and a switching element, and a control unit for controlling ON/OFF of the switching element, provided are an input voltage detection unit for detecting an input voltage of the power factor correction device, an output voltage detection unit for detecting an output voltage, and a coil current detection unit for detecting a coil current that is generated in the coil pursuant to the ON/OFF operation of the switching element.

Abstract: A three-phase boost converter is disclosed, as well as a related control technique. In certain embodiments, the provided boost converter enables efficient transfer of energy from an irregular input power source to a battery storage device or a DC link. To achieve maximum power absorption in such cases, the provided embodiments utilize a variable resistive behavior across each phase of the converter using feedback control.

Abstract: A power source apparatus includes: a first alternating current line; a second alternating current line; an electric power inputting portion including a rectifying circuit for rectifying an alternating current voltage supplied from an alternating current power source, the electric power inputting portion serving to output the rectified voltage to each of the first and second alternating current lines; a first converter including a switching element for converting the alternating current voltage into a first direct current voltage; a second converter for converting the first direct current voltage obtained in the first converter into a second direct current voltage; and a control circuit for carrying out control for driving at least the switching element of the first converter so as to be turned ON or OFF.

Abstract: A charger and discharger for a secondary battery includes a secondary battery coupled to an output stage of the charger and discharger, a first converter circuit including a first pulse voltage generator that outputs a first pulse voltage according to a first duty ratio, and a first inductor that outputs a first current in proportion to a value of an integral of the outputted first pulse voltage with respect to time to a positive electrode terminal of the secondary battery, a second converter circuit including a second pulse voltage generator that outputs a second pulse voltage according to a second duty ratio, and a second inductor that outputs a second current in proportion to a value of an integral of the outputted second pulse voltage with respect to time to a negative electrode terminal of the secondary battery, and first and second controllers controlling the duty ratios of the first and second pulse voltage generators, respectively.

Abstract: A single-phase voltage source AC/DC converter according to the present invention generates a second axis voltage command from difference between a DC voltage detection value at a DC terminal and a DC voltage command value and controls a DC voltage by increasing and decreasing active power with the second axis voltage command. For example, the voltage at the DC terminal is increased by decreasing active power when the DC voltage detection value at the DC terminal is lower than the DC voltage command, while the DC voltage detection value at the DC terminal is decreased by increasing the active power when the DC voltage detection value at the DC terminal is higher than the DC voltage command.

Abstract: A method of balancing current in a vehicle electric system having a system bus, a first battery, a first bi-directional battery voltage converter selectively transferring a first current between the first battery and the system bus, a second battery, a second bi-directional battery voltage converter selectively transferring a second current between the second battery and the system bus, and a controller controlling the first bi-directional battery voltage converter and the second bi-directional battery voltage converter. The method includes sensing the first current and sensing the second current. The first bi-directional battery voltage converter and the second bi-directional battery voltage converter are controlled so that the first current and the second current are equal portions of a load current supplied to an electrical load connected to the system bus.

Abstract: A modified bootstrap circuit utilized, for example, in a high voltage DC/DC CMOS buck converter to convert a high input voltage (e.g., 24V) to a regulated voltage (e.g., 4V) for use, for example, by an LED driver circuit. The bootstrap circuit utilizes a feedback diode and a PMOS switch to avoid high reverse diode voltages across a low voltage bootstrap diode. A bootstrapped buck converter implements the bootstrap circuit to generate a high gate voltage on a high-side NMOS switch during all operating phases. The PMOS switch is controlled by the NMOS switch's output voltage to pass a system voltage (e.g., 5V) through the bootstrap diode whenever the output voltage drops low (e.g., 0V), and to shut off when the output voltage subsequently rises such that the feedback diode forward biases to pass the output voltage to the anode of the bootstrap diode.

Abstract: This invention offers a power supply circuit that is capable of improving a power factor as well as reducing a ripple current of an input/output of the power supply circuit due to switching of a switching device. The power supply circuit is provided with a first power supply circuit including first and second switching devices, a second power supply circuit including third and fourth switching devices and a switching control circuit. The switching control circuit controls the switching devices so that the first switching device and the third switching device are turned on and off at timings different from each other when an alternating current voltage from an alternating current power supply is positive, and the second switching device and the fourth switching device are turned on and off at timings different from each other when the alternating current voltage is negative.

Abstract: A power factor correction converter and a power factor correction conversion device, includes two groups of bidirectional switches, an autotransformer, a boost inductor, a bus filter capacitor, two front bridge arms; and a rear bridge arm; the front end of each group of bidirectional switches are connected to a coil of the autotransformer in one-to-one correspondence, and a rear end of each group of bidirectional switches is connected to one end of an AC input power grid; a central tap of the autotransformer is connected to an output end of the boost inductor, and an input end of the boost inductor is connected to the other end of the AC input power grid; a front end of each group of bidirectional switches is connected to a front bridge arm, and a rear end is connected to the rear bridge arm.

Abstract: A control circuit for a buck-boost circuit includes an inductor current sensor and an input current generator. The input current generator accepts a signal from the inductor current sensor and outputs a synthesized and integrated signal representing the average input current to the buck-boost circuit. The input current generator averages the inductor current signal or a zero signal based on the state of the buck switch in the buck-boost circuit.

Abstract: A power factor correction (PFC) controller includes a first integrator coupled to integrate an input current of a PFC converter. A first signal is generated in response to the first integrator to end an on time of a power switch of the PFC converter. A second integrator is coupled to integrate a difference between a constant voltage and an input voltage of the PFC converter. A second signal is generated in response to the second integrator to end an off time of the power switch of the PFC converter. A driver circuit is coupled to vary the switching frequency of the power switch of the PFC converter in response to the first and the second signals and to output a third signal to switch the power switch of the PFC converter to control the input current to be substantially proportional to the input voltage.

Abstract: A resonant control circuit for a power converter is provided. The resonant control circuit includes a microcontroller, a switching-signal timer, a first PWM timer, and a signal detection circuit. The microcontroller has a memory circuit, and the memory circuit includes a program memory and a data memory. The switching-signal timer generates a first switching signal coupled to switch a transformer. The first PWM timer generates a PWM signal coupled to control a synchronous rectifying transistor of the power converter for synchronous rectifying. The signal detection circuit is coupled to an output of the power converter for generating a feedback data from a feedback signal. The microcontroller controls the first switching signal by programming the switching-signal timer in accordance with the feedback data. The microcontroller controls the first PWM signal by programming the first PWM timer in response to the first switching signal.

Abstract: Disclosed is a power supply including a first voltage generating unit that generates a first voltage from an external power supply; a second voltage generating unit that generates a first predetermined voltage and supplies the generated first predetermined voltage to the load; a third voltage generating unit that generates the first predetermined voltage and supplies the generated first predetermined voltage to the load; and a controller that causes the first voltage to be greater than or equal to a second voltage during a first mode, and causes the first voltage to be less than the second voltage during a second mode. During the first mode, the power is supplied from the second voltage generating unit and the third voltage generating unit to the load, and during the second mode, the power is supplied from the third voltage generating unit to the load.

Abstract: The present invention pertains to a boost power factor correction (PFC) controller. In one embodiment, a boost PFC controller for an AC/DC converter can include: an off signal generator that compares an inductor current sample signal against a first control signal, where the inductor current sample signal increases during an on time of a power switch of the AC/DC converter, and the off signal generator generates an off signal when the inductor current sample signal reaches the first control signal level; and an on signal generator that compares a second control signal against a third control signal, where the second control signal increases during the off time of the power switch, and the on signal generator generates an on signal when the second control signal reaches the third control signal level.

Abstract: A current controlled power converter includes a converting part configured to convert a three-phase ac voltage into a dc voltage or converts a dc voltage into a three-phase ac voltage, ac side current detection portions configured to detect an ac side current of the converting part, dc side current detection portions configured to detect a dc side current of the converting part, and a control section configured to control the converting part by pulse-width modulation using a spatial vector modulation method based on the ac side current detected by the ac side current detection portions and the dc side current detected by the dc side current detection portions. The control section corrects an amplitude error of the ac side current detected by the ac side current detection portions, and an offset error of the ac side current detected by the ac side current detection portions.

Abstract: An exemplary embodiment of the present invention relates to a switch controller, a method for controlling a switch, and a power supply including the switch controller. According to the exemplary embodiment of the present invention, an AC input passed through a dimmer is rectified such that an input voltage is generated, and the input voltage is transmitted to the power switch. A charging current is generated using a voltage that depends on the input voltage, a zero cross-point at which the input voltage becomes zero voltage is detected using a detection voltage output from a current source, and a reference signal synchronized at the detected zero cross-point is generated.

Abstract: The present invention relates to a power factor correction circuit and a driving method thereof. The power factor correction circuit receives an input voltage and maintains an output voltage at a constant level by controlling switching operation of a power switch connected to an inductor that supplies the output voltage. In this case, the power factor correction circuit controls switching operation of the power switch by differentiating a control structure for an output voltage respectively according to a stabilization period during which the output voltage is constantly maintained and a start-up period during which the output voltage is increased before being stabilized. In addition, the power factor correction circuit controls the switching operation of the power switch according to the control structure of the start-up period during a predetermined correction delay period from a time that the stabilization period starts.

Abstract: A multi-voltage power supply includes a transformer, a first output circuit to generate a first output voltage using a voltage transferred to a secondary winding of the transformer, and a first output voltage controller to control a voltage supplied to the primary winding of the transformer according to the first output voltage. The multi-voltage power supply includes second through Nth output circuits to generate second through Nth output voltages using the voltage transferred to the secondary winding of the transformer, and second through Nth output voltage controllers performing control in order to linearly output the second through Nth output voltages by feeding back the second through Nth output voltages.

Abstract: In a step-down switching regulator, a switching element is a high-voltage NMOS transistor, turned on and off based on a control signal generated by a controller, and charges an inductor with an input voltage input to an input terminal. A first drive circuit is a low-voltage MOS transistor and turns on and off the switching element based on the control signal. A voltage generator generates a predetermined first power supply voltage not greater than a withstand voltage of the low-voltage MOS transistor. A capacitor is connected in parallel with the first drive circuit and stores charge from the voltage generator to supply power to the first drive circuit. One end of the capacitor is connected to a junction node between the switching element and the inductor, and the other end of the capacitor is supplied with the first power supply voltage generated by the voltage generator.

Abstract: A circuit arrangement with standby mode minimising power and/or current consumption having a mains AC power supply terminals and an active circuit capable of converting said mains AC power to lower voltage DC levels for operating in an active mode or in a standby mode as required by an appliance such that the selection of the current sensing resistor value for said current sensing resistor limits the maximum peak current through the FET so that the current sensing resistor arrangement is capable of providing significant increases in a steeper rise time of the current at around mains AC power supply zero crossing, so that current is pulled high while the mains AC power supply voltage is low.

Abstract: A three-phase resonant cyclo-converter including a closed loop control module for controlling the switching frequency of the cyclo-converter, the closed loop control module including: a voltage signal development module arranged to develop a voltage signal representative of a voltage output waveform of the cyclo-converter, a storage module arranged to accumulate voltage signal values for phase portions of the voltage output waveform, where the voltage signal values are based on a voltage error signal and accumulated historical voltage signal values for the same corresponding phase portions, and a switching frequency control module arranged to develop a switching frequency control signal to control the switching frequency of the cyclo-converter based on the accumulated voltage signal values for corresponding phase portions of the voltage output waveform, and a proportional voltage signal based on a difference between the developed voltage signal and a reference voltage signal.

Abstract: A light source device including: a boost-type conversion unit configured to convert an input AC voltage into a DC voltage; a detection unit configured to detect a voltage value of the input AC voltage; and a control unit configured to control the brightness of a light source unit on the basis of an input image signal. The control unit changes the timing of brightness change of the light source unit according to a voltage value detected by the detection unit.

Abstract: The present invention is related to a switched-mode power supply. It is also related to a LED lighting system and driver which comprise such a switched-mode power supply. In addition, the present invention is related to a method for electrically driving a load. According to the present invention, the switched-mode power supply is switched from a charging state, in which an energy storage is charged, to a discharging state, in which the energy storage feeds a load, when a current limit has been exceeded. This current limit is set proportional to an instantaneous voltage outputted by the rectifier.

Abstract: A converter can include at least two power stages. Each power stage can include a power factor control circuit. An active shared control circuit for a three power stage system receives at least three sense signals. Each of the sense signals is associated with a parameter of the respective one of the power stages. The control circuit provides at least three control signals. Each of the control signals being associated with the respective power factor control circuit of the power stages. The active share control circuit balances the current supplied by the power stages via the control signals.

Abstract: A three-phase AC to DC converter includes a three-phase AC power supply, a three-phase rectifier bridge circuit that is connected to the three-phase AC power supply and includes rectifying devices which are connected in a bridge configuration, a three-phase full-bridge circuit that includes two serially-connected switching devices for each of three phases, the two serially-connected switching devices being connected at an output side of the three-phase rectifier bridge circuit, and includes reverse blocking diodes which are connected in parallel to the respective switching devices, a reactor that connects the three-phase full-bridge circuit to the three-phase AC power supply, a smoothing capacitor connected to an output side of the three-phase full-bridge circuit, DC voltage detection means that detects an output voltage, power supply phase detection means that detects a power supply phase of the three-phase AC power supply, and pulse width modulator that outputs PWM signals which control the switching device

Abstract: A driver for a switch, method of driving a switch, and a power converter employing the same. The driver for the switch includes a first driver switch coupled to a terminal of the switch. The driver also includes a second driver switch inverted with respect to the first driver switch and coupled to another terminal of the switch, wherein the first and second driver switches are configured to provide a drive signal to a control terminal of the switch.

Abstract: An exemplary non-isolated DC-DC converter for a solar power plant, can be adapted to connect to a full-bridge inverter. The converter includes positive and negative input terminals, and positive and negative output terminals. A plurality of switches, diodes, inductors and capacitors are connected in a circuit configuration to the input and output terminals. A control means is connected to the circuit for controlling the switching of a first, second, and third switch between an open and closed state.

Abstract: A method for varying power factor is applied to a power factor correction circuit and a rectified voltage. The rectified voltage is transmitted to the power factor correction circuit. The method for varying power factor is to change the conduction pulses of the power factor correction circuit to change the conduction current and the power factor.

Abstract: According to one embodiment, a power conversion apparatus determines a peak value of circuit current in each pulse cycle, from a corrected output voltage value by subtracting a predetermined reference voltage from an output voltage detected by the output voltage detector, and an input voltage detected by the input voltage detector. The pulse signal output unit outputs a pulse signal to the first switch when the polarity of input voltage is positive, and outputs a pulse signal to the second switch when the polarity of input voltage is negative. A pulse signal turns on in synchronization with a clock signal input from the oscillator, and is kept on until the circuit current detected by the circuit current detector reaches the peak value. A pulse signal turns off when the circuit current reaches the peak value, and turns on again in synchronization with the next clock signal.

Abstract: A bridge rectifier is established by MOSFETs instead of diodes. The MOSFET bridge rectifier includes a voltage detector to detect the voltages of two AC input terminals of the MOSFET bridge rectifier, for identifying the positive and negative half cycles of an AC voltage input to the MOSFET bridge rectifier, thereby accurately controlling the MOSFETs.

Abstract: An inrush protection circuit is provided for an electronic ballast for powering HID lamps. A first resistor is positioned along a low potential side of the circuit and a switching element coupled in parallel with the first resistor. Second and third resistors are coupled in series and effective to receive DC input power from a DC source, with a first node between the second and third resistors further coupled to the gate of the switching element. A capacitor is coupled in parallel with the third resistor to provide a smoothed DC voltage to the gate of the switching element. A discharging circuit includes a diode and a fourth resistor coupled in series between the first node and the high potential side of the circuit, and is arranged to conduct discharging current from the capacitor until the voltage across the capacitor discharges below a predetermined voltage after the DC input power is removed from the circuit.

Abstract: A power factor correction (PFC) system includes a comparison module, an adjustment module, a compensation module, and a duty cycle control module. The comparison module measures N currents having different phases, and generates (N?1) comparisons based on the N measured currents, wherein N is an integer greater than one. The adjustment module determines (N?1) time advance adjustments based on the (N?1) comparisons, respectively. The compensation module generates N compensated versions of an input alternating current (AC) line signal based on the input AC line signal, a sinusoidal reference signal, and the (N?1) time advance adjustments, wherein the sinusoidal reference signal is synchronized to the input AC line signal in phase and frequency. The duty cycle control module controls PFC switching based on the N compensated versions of the input AC line signal.

Abstract: Implemented are a switching power supply device and a light-emitting diode lighting device in which a variation in load current can be suppressed against a wide range of variation in AC voltage. The configuration of the switching power supply device and the light-emitting diode lighting device includes: a rectifier unit which rectifies AC input voltage and outputs pulsating-current voltage; a power converting unit which receives the pulsating-current voltage and supplies a predetermined load current to a load; a current detecting unit which detects the load current; a drive control unit which controls the power converting unit to regulate the load current to a constant level; and an input voltage detecting unit which detects a variation in the AC input voltage. The drive control unit controls the power converting unit depending on the variation in the AC input voltage detected by the input voltage detecting unit.

Abstract: The present invention relates to a power factor correction (PFC) controller. In one embodiment, a boost PFC controller configured in an AC/DC converter can include: (i) a conductive signal generator configured to receive a first sampling signal, and to generate a conductive signal according to the first sampling signal and a first control signal; (ii) a shutdown signal generator configured to compare a second control signal against a third control signal, and to generate a shutdown signal when the second control signal reaches a level of the third control signal; and (iii) a logic controller coupled to the conductive signal generator and the shutdown signal generator to control a switching state of a power switch in AC/DC converter.

Abstract: A high voltage full wave rectifier circuit having complementary serially connected low voltage MOSFET stacks provides high voltage rectifier capability. The MOSFET stacks are coupled to a pair of cross coupled MOSFETs that provide a full wave rectified output voltage. The state of the MOSFETs in the MOSFET stacks is controlled by resistors coupled between the rectifier output and a time varying input signal. The resistance values of the resistors are selected to maintain operation of the stacked MOSFETs below their breakdown voltages. A pair of diodes is connected between ground and the MOSFET stacks. A plurality of diode connected MOSFETs are connected between the rectifier output and the resistors to establish bias voltages on the gates of the MOSFETs in the MOSFET stacks to control operation of the rectifier during input voltage cycles. A voltage doubler circuit is also described where low voltage MOSFETs are utilized in a novel configuration to provide high voltage doubling capability.

Abstract: A circuit arrangement includes a switching element that switches a load current, a current-limiting element connected in series to the switching element, a bistable first relay connected in parallel to the switching element and the current-limiting element, and a control circuit that switches the power-supply unit from a first operating state to a second operating state in which a load current for generating a DC voltage flows from the power grid to the power-supply unit, such that the control circuit turns on the switching element for a first time period during switching of the power-supply unit from the first to the second operating state, to turn the bistable relay on during the first time period, and to turn the switching element off at the end of the first time period.

Abstract: In at least one embodiment, an electronic system adapts current control timing for half line cycle of a phase-cut input voltage and responsively controls a dimmer current in a power converter system. The adaptive current control time and responsive current control provides, for example, interfacing with a dimmer. The electronic system and method include a dimmer, a switching power converter, and a controller to control the switching power converter and controls a dimmer current. In at least one embodiment, the controller determines a predicted time period from a zero crossing until a leading edge of a phase-cut input voltage and then responsively controls the dimmer current to, for example, reduce current and voltage perturbations (referred to as “ringing”), improve efficiency, and reduce an average amount of power handled by various circuit components.

Abstract: A control device controls a switching converter that converts an alternating supply voltage to a regulated voltage and comprises a switch connected to an inductor. The control device is adapted to control the on period and the off period of said switch for each cycle. The control device comprises a ramp generator adapted to generate a ramp voltage, a comparator adapted to determine the final instant of the on period of the switch by crossing the ramp voltage with a first voltage. The control device has a first signal representing a current through the inductor and a second signal representative of the current flowing through at least one element of the converter. The control device is adapted to control the closing of said switch according to said first signal and comprises a synchronizer adapted to synchronize the start of the ramp voltage with the zero crossing of said second signal.

Abstract: The magnitude and wave shape of instantaneous alternating current and power delivered from a converter's single phase alternating current output is controlled by a closed loop power control scheme independent of the direct current input voltage to the converter. A fast averaging methodology for the value of control magnitude and wave shape of the instantaneous power delivered from the alternating current output can be used in the closed loop power control scheme to limit the magnitude of delivered power. The closed loop power control scheme can be used in both power grid-tied applications and stand-alone non-powered load line applications.

Abstract: Reliability enhanced systems are shown where an short-lived electrolytic capacitor can be replaced by a much smaller, perhaps film type, longer-lived capacitor to be implemented in circuits for power factor correction, solar power conversion, or otherwise to achieve DC voltage smoothing with circuitry that has solar photovoltaic source (1) a DC photovoltaic input (2) internal to a device (3) and uses an enhanced DC-DC power converter (4) to provide a smoothed DC output (6) with capacitor substitution circuitry (14) that may include interim signal circuitry (28) that creates a large voltage variation for a replaced capacitor (16). Switchmode designs may include first and second switch elements (17) and (18) and an alternative path controller (21) that operates a boost controller (22) and a buck controller (23) perhaps with a switch duty cycle controller (32).

Abstract: An example controller for use in a power supply includes a zero crossing detection (ZCD) circuit, a threshold detection circuit, and a punctuated switching control circuit. The ZCD circuit generates a ZCD signal that pulses each zero-crossing of an ac input voltage. The threshold detection circuit receives and compares an output of the power supply with a threshold reference. The punctuated switching control circuit generates a switching signal to control a switch to regulate the output of the power supply. The switching signal is generated to have intervals of switching and intervals of no switching, where each interval of switching begins responsive to the output of the power supply dropping below the threshold reference and each interval of no switching begins responsive to the output rising above the threshold reference. Each interval has a beginning that is synchronized with a pulse of the ZCD signal.

Abstract: A zone addressing circuit is provided for an electronic ballast having a boost inductor with an auxiliary winding. The zone addressing circuit includes a first circuit branch coupled to a first addressing input terminal, a second circuit branch coupled to a second addressing input terminal, and a third (common) branch coupled on a first end to a third addressing input terminal and on a second end to the auxiliary winding of the boost inductor for providing a high frequency input pulse signal to excite the first and second branches. The first branch generates a first digital output for the zone addressing circuit when coupled to the common branch, and the second branch generates a second digital output for the zone addressing circuit when coupled to the common branch. A controller adjusts a dimming level of the ballast based on the first and second digital outputs from the zone addressing circuit.