Abstract: In a power generation system of this invention, the outputs from power generation layers electrically connected in series are input to corresponding power conversion devices, and boosted outputs are connected in parallel and fed to a load. Alternatively, the output from one of power generation layers electrically connected in series is input to a first power conversion device, and the serial output and the boosted output from the first power conversion device are connected in parallel, input to a second power conversion device, boosted, and fed to the load. Since the two power generation layers can be individually output-controlled, each power generation layer can be optimized basically without considering current balance. Since the optical spectrum utilization efficiency increases, the power generation efficiency increases. In addition, since the power can be fed not to separate loads but to one load, the convenience largely increases.

Abstract: A photovoltaic inverter control method includes steps of monitoring a variation in output voltage of a solar battery by a power and voltage monitoring circuit (51) and, when the variation occurs, accelerating or decelerating an electric motor (3) to maximize the output voltage of the solar battery (1), whereby the electric motor for driving, for example, a pump and a fan by the solar battery as a power source can be driven by a photovoltaic inverter always at the maximum power point of the solar battery.

Abstract: A method for driving a neutral point-clamped multi-level voltage source inverter supplying a synchronous motor is provided. A DC current is received at a neutral point-clamped multi-level voltage source inverter. The inverter has first, second, and third output nodes. The inverter also has a plurality of switches. A desired speed of a synchronous motor connected to the inverter by the first second and third nodes is received by the inverter. The synchronous motor has a rotor and the speed of the motor is defined by the rotational rate of the rotor. A position of the rotor is sensed, current flowing to the motor out of at least two of the first, second, and third output nodes is sensed, and predetermined switches are automatically activated by the inverter responsive to the sensed rotor position, the sensed current, and the desired speed.

Abstract: The invention describes a system for electrical transmission in the field of garments and a corresponding transmitter for this. Electrical circuits in garments are coupled, preferably inductively in a wireless manner with electrical devices and/or electrical circuits in other garments, wherein electrical energy is transmitted via the coupling. Energy transmission in both directions is preferably possible, wherein a distributed system results with sources and devices that can be coupled with each other. The efficiency of the inductive energy transmission is increased by regulation of the frequency, preferably using resonance. In addition, means for information transmission are proposed.

Abstract: An AC power supply (10) can be connected in parallel with similar supplies to drive loads (16). Each of the AC power supplies (10) incorporates a discrete controller functioning based on parameters sensed locally and without reference to any of the other supplies.

Abstract: A power source (120) supplies an input voltage (V 1). A voltage conversion circuit (130) converts the input voltage (V1) from the power source (120) into an operating voltage (V2) to be used to drive an electric load (150). A detection circuit (170) measures an insulation resistance value (R) on the output side of the voltage conversion circuit (130). A control circuit (160) controls a voltage conversion ratio (K (K=V2/V1)) in the voltage conversion circuit (130), which is expressed as a ratio of the operating voltage (V2) to the input voltage (V1), in accordance with the insulation resistance value (R) detected by the detection circuit (170). The control circuit (160) sets the voltage conversion ratio (K) such that the operating voltage (V2) becomes lower at the time of degradation of an insulation resistance than at the time of normal operation thereof.

Abstract: A power-saving effect displaying unit includes a power-consumption computing unit that calculates power consumption based on a voltage obtained by an output-voltage computing unit and a current obtained by a current detecting unit. A power-saving-effect generating unit acquires a power-saving effect based on the power consumption. A display displays an instantaneous power-saving effect and an integration value of the power-saving effect under operation with the inverter, with respect to commercial operation, based on the instantaneous power consumption under the operation with the inverter calculated by the power-consumption computing unit, and on electric characteristic data obtained by comparing with the power consumption under the commercial operation.

Abstract: In a switching power supply and a control method for the same in accordance with the present invention, a first error amplifier generates a first error signal by comparing the output signals of a plurality of converters with a reference voltage, an arithmetic unit generates a single output signal by adding the currents output from the rectifying means of the plurality of converters, a second error amplifier generates a second error signal by comparing the single output signal with the output of the first error amplifier, and PWM signal generators generate PWM signals on the basis of the output signal of the second error amplifier to PWM control each of a plurality of switching devices.

Abstract: An active damping arrangement for a power conditioning circuit comprising a converter or an inverter and an electronically driven output line having an output terminal for connecting to an external load, the active damping arrangement comprising an inductor-capacitor low-pass output filter (OPF) for connecting between an output of the inverter/converter (PWMVC or BBHCC) and the output terminal; means for sensing current in or voltage across the capacitor or voltage between one end of the capacitor (C) and an effective neutral point; means for multiplying the sensed voltage or current by a coefficient G to provide a damping signal, and means for feeding back the damping signal to an input of the inverter/converter (PWMVC or BBHCC), thereby to damp the output of the inverter/converter.

Abstract: The present invention relates to an isolated-type switching power supply apparatus, which includes a power supply, a transformer being connected to said power supply, a switching element for switching an electric current going through a primary coil of the transformer so that energy generated on the primary side of the transformer is sent to the secondary side in accordance with the operation of the switching element. The present invention has a modulating circuit for modulating an output on the secondary side of said transformer, a transmitting rout for transmitting an output of the modulating circuit to the primary side of the transformer, a demodulating circuit for demodulating the output transferred through the transferring rout; and the controlling circuit controls the switching element in accordance with an output of the demodulating circuit and the controlling circuit is disposed on the primary side of the transformer.

Abstract: A system is provided for sensing a motor current from a three phase inverter. A first resistor is coupled between a first transistor of the inverter and a supply voltage, and a second resistor is coupled between a second transistor of the inverter and ground. Circuitry coupled to the first and second resistors generates an upper and lower current. When the first transistor is active, the upper current is proportional to the sum of a reference voltage and a voltage across the first resistor, and the lower current is proportional to the reference voltage. When the second transistor is active, the upper current is proportional to the reference voltage, and the lower current is proportional to the sum of the reference voltage and a voltage across the second resistor. Based on the difference of the lower and upper currents, the circuitry provides an output current proportional to the motor current.

Abstract: A method for operating parallel-connected inverter modules, wherein two or more inverter modules (A, B, C) are connected in parallel to feed the same load. Each inverter module has two or more output phases (u, v, w) for supplying electric power into a two or more phase load by determining the temperature (TAu, TAv, TAw, TBu, TBv, TBw, TCu, TCv, TCw) of each output phase (Au, Av, Aw, Bu, Bv, Bw, Cu, Cv, Cw) in each inverter module, comparing the temperatures of the output phases in each inverter module with the temperatures of the same output phase in other parallel-connected modules, and generating an alarm signal if the temperature of the output phase in an inverter module differs from the temperatures of the same output phase of the other inverter modules more than allowed by a predetermined limit.

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

Abstract: For applying a driving current to a motor, an H-bridge circuit is constructed by a first and a second switching unit and a first and a second linear unit. An error amplifier generates an error signal representative of a difference between the driving current detected by a current detecting circuit and a command current signal. A state control circuit synchronously controls the first and second switching units and a feedback circuit. Through the feedback circuit, the error signal is selectively applied to the first or second linear unit such that one is operated in a linear mode and the other is operated in a nonconductive mode, thereby controlling the driving current to become proportional to the command current signal. The state control circuit further controls a brake circuit for transforming the error signal into a brake signal to operate the first and second linear units simultaneously in a conductive mode.

Abstract: A power converter delivers electrical power from an electrical power source to a load according to a plurality of operation modes corresponding to different levels of input voltage or output current. The power converter comprises a power stage for delivering the electrical power from the power source to the load, a switch in the power stage that electrically couples or decouples the load to the power source, and a switch controller coupled to the switch for controlling the on-times and off-times of the switch according to the plurality of operation modes. Each of the operation modes correspond to associated ranges of at least one of an input voltage to the power converter and an output current from the power converter, where the associated ranges are different for each of the operation modes.

Abstract: A power converter system advantageously employs a modular, bi-directionally symmetrical power converter assembly in a readily customizable configuration to interconnect a direct current power source to a three-phase alternating power grid. Connections external to the power converter assembly are selected to optimize the power converter system for a specific application, such as interconnecting a photovoltaic array to the three-phase electrical power grid. The electrical interconnections of various elements including isolation transformers, voltage sensors, and control switches are optimized to improve efficiency and reliability.

Abstract: The invention is directed to a method, system and device for converting direct current (DC) electrical voltage from a fuel cell to an alternating current (AC) voltage. The inventive method regulates power drawn from the fuel cell and from a battery to maintain a substantially constant DC voltage across a DC bus, and inverts the DC voltage from the DC bus to the AC voltage. The method may further electrically isolate the fuel cell from the load. Also, the inventive method may prevent current from flowing to the fuel cell. The inventive method may also provide a charging current to the battery.

Abstract: A constant current control is performed by PWM, and an analog burst control and a digital burst control are made selectable. The burst controls are selected in the following manner. A capacitor is selected as an element which is to be connected to a triangular signal oscillator circuit, to generate a triangular signal, thereby setting the analog burst control. A resistor is selected as the element to generate a constant voltage, thereby setting the digital burst control. A controller IC is used commonly in both the burst controls.

Abstract: According to the present invention, in a water supply apparatus which converts output power of a solar cell with an inverter to drive a motor pump for pumping up water, a DC brushless motor having no sensor for detecting a position of a rotatable shaft is used as a motor for driving the pump.

Abstract: A generating set includes an engie driven generator (PGM) having two sets of stator windings (Ga and Gb). A bi-directional AC/DC converter (BCo) has its AC input connected to a junction between the two sets of stator windings (Ga and Gb) and its DC input connected to a number of the generator (PGM) is converted into an intermediate DC link by a convertor (Col) to produce an output for a load Lo. In normal operation of the system, an emf generated in one (Ga) of the sets of stator windings is rectified by the bi-direcitonal converter (BCo) to charge the energy storages (ESI-ESN) whilst the remainder of the generator output is fed through the converter to the load (Lo). In the event of a stepped increase in the load demand, the bi-directional converter (BCo) is operated to feed energy from the storage devices (ESI-ESN) to the stator windings (Ga) of the generator (PGM) to impart a driving torque to the generator rotor to accelerte the rotor to meet the increased load demand.

Abstract: A low-cost, easily-miniaturized switching power supply restrains voltage stress on first and second main switches. The switching power supply has small loss and low noise, enables setting of duty factors over a broad range, and has reduced thickness. The first main switch has one end connected with a negative electrode of an input voltage, and the second main switch has one end connected with a positive electrode of the input voltage. A first magnetic element is connected to the first main switch, and a second magnetic element is connected to the second main switch and the first magnetic element. The switching power supply has: a first diode connected to the first main switch, the first magnetic element, and the second magnetic element; a second diode connected to the first diode, the second main switch, and the second magnetic element; and an auxiliary switch between the diodes.

Abstract: A power supply controller having a multi-function terminal. In one embodiment, a power supply controller for switched mode power supply includes a drain terminal, a source terminal, a control terminal and a multi-function terminal. The multi-function terminal may be configured in a plurality of ways providing any one or some of a plurality of functions including on/off control, external current limit adjustments, under-voltage detection, over-voltage detection and maximum duty cycle adjustment. The operation of the multi-function terminal varies depending on whether a positive or negative current flows through the multi-function terminal. A short-circuit to ground from the multi-function terminal enables the power supply controller. A short-circuit to a supply voltage from the multi-function terminal disables the power supply controller. The current limit of an internal power switch of the power supply controller may be adjusted by externally setting a negative current from the multi-function terminal.

Abstract: A power converter includes a first sampling device 5 which samples a first command current value for a power conversion device 2 during a second cycle and produces a second command current value; a second sampling device 6 which samples a first detected current value pertaining to a load 3 and produces a second detected current value; a command voltage value calculator 9 for calculating a command voltage value from the second command current value and the second detected current value; a comparator 11 for comparing the second command voltage value with a triangular wave carrier signal, to thereby produce a first pulse width modulation (PWM) signal; and a multi-pulse prevention device 12.

Abstract: An inverter apparatus is provided with first and second current detectors for detecting the current of two arbitrary phases and further with first and second A/D converters, and they are integrated into one unit. It furthermore stores, in a storage device, a compensation value for compensating for an unbalance between gains of the first current detector and the first A/D converter, and gains of the second current detector and the second A/D converter. By multiplying the detected current value of either one of the detected phases by this compensation value, it equalizes the current feedback gains for both phases.

Abstract: The current in each phase of a multi-phase step motor is monitored and the excess phase current above the set point current, as required on a cycle-by-cycle PWM basis, is reduced thereby bringing each phase current down to the set point. The PWM frequency is automatically adjusted to maintain a minimum number of PWM edges within a portion of the current waveform. A maximum charge/discharge time is specified as a percentage of the PWM period. These provide an accurate independent current control within each phase of a multiphase step motor.

Abstract: An object of the present invention is to provide a turbine generation system in which a starting inverter circuit for starting a turbine generator is additionally employed so that the system comprises a high-power generation inverter and the starting inverter with low-power, thereby utilizing the inverter for multiple purposes. To this end, the present invention comprises an inverter control circuit for deactivating a pulse-width modulation inverter for generation connected to a turbine generator, and first switching means for connecting an internal power supply to the turbine generator, wherein the inverter control circuit controls the starting inverter to supply the turbine generator with power to drive it up to a purge speed and accelerate it to a predetermined starting speed.

Abstract: A power conversion apparatus of this invention includes a power switching device, a voltage sensor, a current sensor, and a device controller connected to the switching device, the voltage sensor, and the current sensor. The voltage sensor detects an output voltage of the switching device to output a first signal depending on the output voltage, and the current sensor detects an output current of the switching device to output a second signal depending on the output current. The device controller includes a driver connected to the switching device and a correcter connected to the driver, the voltage sensor and the current sensor. The driver outputs a third drive signal to the switching device. The correcter monitors a switching loss and a surge voltage by using the first and second signals, and corrects the third signal depending on values of the switching loss and the surge voltage.

Abstract: A universal adapter for use with a rechargeable handheld communication device includes a power module. An AC rectifier is operable to convert an AC power signal into a rectified AC power signal. A DC transformer is operable to receive the AC rectified power signal and output a DC transformed power signal. A top switch feedback circuit is coupled to the DC transformer and is operable to regulate the DC transformed power signal. A DC to DC switching converter is coupled to the DC transformer and is operable to convert the DC transformed power signal to a converted DC power signal. A feedback control circuit is coupled to the DC to DC converter and operable to regulate the converted DC signal.

Abstract: The present invention discloses to a multi-period cycle-alternative switching mode power supply control device, comprising: a power transfer control unit, a dimming bias control, a burst timing control, and a steering logic; wherein said device has a variable multi-period control cycle to effectively control certain power transfer elements of specific nature and assure those elements and the loading at the rear end can operate more efficiently in a reliable range of specific nature.

Abstract: A high-voltage power source apparatus with a simple construction which outputs a voltage by overlapping a DC voltage with an AC voltage. An alternating current (AC) voltage generator generates an AC voltage and outputs the AC voltage to a secondary coil of a transformer. The AC voltage and the DC voltage are developed and simultaneously overlapped from a common secondary coil of the transformer. Thus, separate AC and DC voltage generators are not necessary to produce the overlapped voltage, simplifying construction. The DC portion of the overlapped voltage may be regulated by feeding back a sample of the output voltage to a control circuit which compares the feedback with a reference and regulates the DC portion accordingly. A plurality of the overlapped voltage circuits may be operated in parallel from a single secondary coil of the transformer.

Abstract: A drive controller operator interface and serial protocol therefor are provided for controlling electric motors and other electrical devices which are typically powered by inverters that convert input power to control input signals for the motor or other electrical device. The system includes a removable keypad/display unit controller which can serve a number of drives, as well as an improved serial protocol, that includes a provision for data indicating the type of device to which the drive is attached.

Abstract: An induction heating device prevents an object to be heated from being displaced and buoyed from a mounting surface due to an mutual action of repulsive forces between the object to be heated and an induction heating coil. The induction heating device includes a source-current detector for detecting a source current input to a high-frequency inverter including the induction heating coil and an inverter circuit, a source-current change detector for measuring a change against time of a magnitude of the source current to detect a displacement and buoying of the object to be heated, such as a cooking pot, and a change examining unit. The controller controls an output of the high-frequency inverter in response to a detection result of the change examining unit. The induction heating device prevents the cooking pot from being displaced and buoyed even if the pot is not touched by a user at startup of heating or during the heating operation, and is inexpensive and safe.

Abstract: D.C.-A.C. converting circuit capable of increasing boosting efficiency and reducing noise, including a boosting section composed of serially connected transistors, inductors and capacitors and an A.C. electronic switch part composed of several transistors (electronic switches such as MOSFET, gate throttle, etc.) and capacitors. When the signal for controlling the operation of the transistors is boosted from low potential to high potential, the operation of the transistors is speeded. When cut off, the signal is formed with a negative voltage level pattern, whereby the transistors can be more quickly cut off. The electronic switch part of the circuit is replaceable with several serially connected diodes to also achieve the voltage for increasing boosting efficiency. During discharge, a measure for controlling the current of the circuit is added so as to reduce the noise produced during boosting procedure.

Abstract: The present invention relates to a pulse width modulation control system which is capable of preventing arm short phenomenon and controlling a operation circuit precisely by securing dead time. The present invention comprises a counter which sets initial voltage value differently and outputs chopping wave crossed at its maximum voltage value and minimum voltage value, an adder/subtracter which adds/subtracts signal generated by the counter, a reference voltage value generation unit which is inputted signal outputted from the adder/subtracter and outputs two different reference voltage values to single chopping wave, a comparator which compares reference voltage value generated by the reference voltage value generation unit with voltage value outputted from the adder/subtracter, and an output control unit which outputs PWM (Pulse Width Modulation) positive signal (SPWM+) or PWM (Pulse Width Modulation) negative signal (SPWM−) in accordance with the output voltage value of the comparator.

Abstract: A battery voltage Ef of a fuel cell 1 is detected, and a current instruction value which transformed an electric power instruction value Pfc of the fuel cell is reduced at falling-down of the voltage Ef. A current limiter 8 makes the current instruction value a limit value at the time of the falling-down of Ef, and reduces the limit value according to the fall of Ef. For example, current instruction value is restricted so as to begin to reduce battery current IFC at voltage drop alarm level (first threshold value), and become zero at voltage drop protection level (second threshold value).

Abstract: A switching power supply is provided which suitably restrains voltage stress on a first main switch and a second main switch, can be made at a low cost and can be easily miniaturized. Also a switching power supply is provided which has a small loss and low noise, enables setting of duty factors in a broad range, and is suitable for reduction in thickness.

Abstract: An electrical power system includes an electric power source providing AC power to a load. A wideband voltage controller provides a wideband control signal vector to the electric power source. A fundamental component removal module interfaces to the AC power, receiving a fundamental component Park vector of the AC voltage, and providing a resonant frequency content in Park vector format of the AC current. A narrow band voltage regulator uses a resonant component Park vector of the AC current and the resonant frequency content in Park vector format to provide a narrow band output vector signal. A dead band compensating circuit rotates narrow band output vector signal by a transport lag compensation angle to provide a compensated control signal vector to the electric power source. The wideband control signal vector and compensated control signal vector are used to regulate the AC power so that the resonant frequency content is attenuated.

Abstract: A power semiconductor device comprises a power switching element having two main electrodes and one control electrode, a metal electrode connected to one of main electrodes of the power switching element, and a protection circuit for controlling an operation of the power switching element so that a main current flowing between the main electrodes of the power switching element is detected and the main current is limited when the detected main current is determined to be an overcurrent. The protection circuit detects the main current flowing through the power switching element by detecting a voltage between predetermined two points of the metal electrode.

Abstract: A power supply controller having a multi-function terminal. In one embodiment, a power supply controller for switched mode power supply includes a drain terminal, a source terminal, a control terminal and a multi-function terminal. The multi-function terminal may be configured in a plurality of ways providing any one or some of a plurality of functions including on/off control, external current limit adjustments, under-voltage detection, over-voltage detection and maximum duty cycle adjustment. The operation of the multi-function terminal varies depending on whether a positive or negative current flows through the multi-function terminal. A short-circuit to ground from the multi-function terminal enables the power supply controller. A short-circuit to a supply voltage from the multi-function terminal disables the power supply controller. The current limit of an internal power switch of the power supply controller may be adjusted by externally setting a negative current from the multi-function terminal.

Abstract: A converter has a resonance circuit with an auxiliary valve (18), an inductor (17) and capacitive members (15) for assisting the commutation of the converter. A control arrangement (24) is adapted to control turning-on and turning-off of controllable semiconductor devices of the main valve of the converter and controllable semiconductor components of the auxiliary valve. Means are arranged for measuring the current in the phase output (10) of the converter. When carrying out two subsequent commutation processes for changing the phase potential on the phase output from the potential of a first of the poles of a direct voltage side of the converter to that of a second of the poles and then back to the one of the first pole the second commutation process is started before the first one has been completed.

Abstract: The invention relates to a resonant converter (200, 300). The resonant converter (200, 300) consists of a furst circuit, primarily a DC circuit (201, 301) connected to a resonant circuit (207, 307) which is further connected to a switch/filter circuit (212, 312) which is connected to a second circuit, primarily an AC circuit (219, 319).

Abstract: A DC-to-DC converter having an input voltage and an output voltage, which includes a circuit topology such that, in operation, the input and output voltages have the same polarity, and that a magnitude of a ratio of the input voltage to the output voltage of the DC-to-DC converter is capable of being equal to, greater than, or less than one. The circuit topology is also such that a same at least one capacitor and alternative coils of a two-coil inductor are employed in a primary and a secondary circuit loop of the DC-to-DC converter. The primary and secondary circuit loops are not electrically isolated.

Abstract: The present invention is directed to a flexible converter. A flexible converter of the present invention may provide a desired output utilizing a variety of methods, systems and apparatus without departing from the spirit and scope of the present invention. For instance, a method may include loading an initial configuration including at least one power characteristic into a converter. The converter is suitable for providing power to an electrical device. A power output is generated having the at least one power characteristic. The power output is monitored with a comparator, the comparator suitable for measuring the at least one power characteristic.

Abstract: An active backup power supply with PFC and power output regulation comprises a power factor correction (PFC) circuit, a backup battery, an inverter and a control circuit. The said PFC circuit outputs current drawn as low THD (total harmonic distortion) and non-pulsating current from municipal power source. The said inverter connects to the PFC circuit and the backup battery at one end and outputs a precisely regulated power source at the other end. The said controller is to control the voltage relation between the PFC circuit and the inverter, so the PFC circuit is controlled in voltage boost mode to draw non-pulsating current from municipal power. With the above-mentioned components, the present invention enables an output power with PFC and voltage regulation to the load device (FIG. 3).

Abstract: An anomaly detection circuit of an inverter detects behavioral anomaly such as disconnection discharge of a circuit wiring or discharge between high and low voltage parts with high accuracy and prevents continuation of behavioral anomaly of the device. The anomaly detection circuit of the inverter comprises a current change detector, a detection signal output part wherein the current change detector detects change in a circuit current flowing in circuit wirings of the inverter leading from the DC input to the load through the intermediary of magnetic flux change(&Dgr; &phgr;) which occurred to the circuit wiring while the detection signal output part outputs a detection signal (Vs) representing behavioral anomaly when the change in circuit current detected by the current change detecting part exceeds a predetermined level.

Abstract: A method and apparatus for supplementing electrical power production during peak demand power consumption is presented. A solar power conditioner converts DC electrical power provided by solar panels (or otherwise) to AC power and uses this to supplement main AC electrical power generated by a power utility (or otherwise) when needed. Both the DC power and the main AC power are digitalized by analog to digital (A/D) converters and continuously monitored by a central processor (CPU). The CPU aims to match the generated AC power of the inverter to that of the main AC power and, after tripping a breaker, supplements the main AC power with that of the converted power provided by the solar panels. In such a supplementary role, the solar power conditioner can be inserted into a utility's distributed power grid.

Abstract: The power supply apparatus (10) comprises an input (12), first and second outputs (14, 16) and conversion circuit (18) for conversion of the electric current which are connected between the input (12) and the outputs (14, 16). The conversion circuit (18) comprises a transformer (20) comprising a primary winding (20A) supplied by the input electric current and first and second secondary windings (20B, 20C) respectively supplying the first and second outputs (14, 16) by way of first and second shaping circuits (22, 24). The first shaping circuit (22) comprises a regulating circuit (48) adapted to act on the electric current feeding the primary winding (20A). The regulating circuit (48) is adapted to effect regulation in dependence on a signal from the first shaping circuit (22). The second shaping circuit (24) comprises autonomous circuitry (86, 88) for regulating the current provided by the second output (16).

Abstract: A power supply controller having a multi-function terminal. In one embodiment, a power supply controller for switched mode power supply includes a drain terminal, a source terminal, a control terminal and a multi-function terminal. The multi-function terminal may be configured in a plurality of ways providing any one or some of a plurality of functions including on/off control, external current limit adjustments, under-voltage detection, over-voltage detection and maximum duty cycle adjustment. The operation of the multi-function terminal varies depending on whether a positive or negative current flows through the multi-function terminal. A short-circuit to ground from the multi-function terminal enables the power supply controller. A short-circuit to a supply voltage from the multi-function terminal disables the power supply controller. The current limit of an internal power switch of the power supply controller may be adjusted by externally setting a negative current from the multi-function terminal.

Abstract: The voltage applied to a power converter is detected by a voltage detector, a function generator produces a voltage proportional to this detected voltage, and a high-pass filter detects an AC component superimposed on the voltage. An adder adds a bias voltage to this AC component, and an adder adds the output from the adder and the output from the function generator. The output from the adder is compared with a triangular wave produced from a rectangular wave generator, and a switching element is controlled to make switching operation according to the compared result. When a DC current is decreased by the AC component, a resistance current Ib is increased so that the AC components superimposed on the current and resistance current can be cancelled out.

Abstract: A kind of programmed isolating starting system and method of a switching power supply. A pulse width modulator (PWM) is placed in the secondary circuit of the invention. The programmed isolating starting circuit provides the necessary power for controlling the IC of the PWM when the system starts. Once the system starts, the programmed isolating starting circuit does not work anymore, and the successive power is provided by the secondary output. If it is necessary to restart, the hardware and the program can automatically restart the system in the invention. At the same time, the system can be started and the working voltage can be provided via the hardware and the software even when the input voltage has a very large difference.