Abstract: A miniaturized switching power supply has an output circuit for supplying gate drive to a power FET. The output circuit incorporates a pair of series connected transistors with a zener diode connected to the base of one of the transistors to limit the gate drive to the FET.

Abstract: A charge pump circuit for providing a bipolar output that substantially doubles the unipolar voltage input by utilizing a three-phase clock signal to charge a first capacitor in response to the first phase of the three-phase clock signal, then in response to either the second or third phase of the clock signal connect the first capacitor in series between the positive voltage input terminal and positive voltage output terminal to generate an output voltage which is positive in polarity and substantially double the voltage of the input source, then in response to the other of the second and third clock phases connect, between the input terminals, the first and second capacitors in series for providing a second polarity voltage across the second capacitor which is substantially double the source voltage and during either the following first or second clock pulse connect the second capacitor with its positive electrode connected to the negative input terminal and its negative electrode connected to the negative

Abstract: A control circuit for a switching power supply. First and second transformers for outputting different voltages are controlled by first and second switches. The switches are controlled by first and second control means which are turned on when the applied voltage exceeds a specified start-up voltage, and off when the voltage drops below a lower shut-down voltage. A reference voltage charges a capacitor, which is then added to the operating voltage of the circuit so that the start-up voltage can be applied even though the operating voltage of the circuit is lower than the start-up voltage. A third control means controls the change from one switch to the other at the desired voltage levels. The use of lower operating voltages allows the circuit to more rapidly drop below the shut-down voltage when abnormal operation occurs.

Abstract: A shunt regulator for isolating a power supply and load is described which automatically adjusts the quiescent current though the shunt, and therefore its available dynamic range, in proportion to the load current fluctuations. A signal proportional to the load current fluctuations is differentiated, detected, integrated and fed back to control the bias on the shunt. When large load current fluctuations occur, the operating point of the shunt is shifted to higher current values so as to provide a large dynamic regulation range. When load current fluctuations are small or zero, the operating point of the shunt is moved toward cut-off, thereby reducing the dynamic range of the shunt and conserving power. This substantially reduces the power dissipation in the regulator because the shunt need not be constantly biased to handle the largest anticipated load current fluctuation.

Abstract: A programmable reference voltage generator includes a diode arrangement for generating a reference voltage in response to a control current. An array of memory cells is provided for adjusting the control current, the memory cell array including a plurality of memory cells connected to the diode arrangement through a plurality of current paths. Each of the memory cells is disposed to conduct current when programmed to store a first binary value, and to not conduct current when programmed to store a second binary value. A programming circuit is used to store a selected one of the first and second binary values in each memory cell, thereby causing the reference voltage to assume a selected magnitude.

Abstract: A digital controlled converter (100) for converting an input signal to a direct current signal having a clock generator (104) for generating a high frequency clock timing signal and a driver circuit (106) for controlling the passage of the high frequency clock timing signal within the converter (100). A power output stage (102) which provides an output signal is controlled by the driver circuit (106). A control loop (108) is provided for sensing and converting the output signal to a command signal. A latch (128) is utilized for latching the command signal and for controlling the state of the driver circuit (106). The latch (128) is reset at the rate of the high frequency clock timing signal and updated with the command signal to provide incremental correction to the output signal. The converter (100) comprises a transient response to variations in load proportional to the high frequency clock timing signal.

Abstract: Holdover circuitry for an off line switcher, including a DC-to-DC converter, maximizes holdover time, during source voltage failures, by commutating a precharged holdover capacitor to the input of a power factor correcting preregulator. This limits the size of the holdover capacitor required without any loss in holdover time. Reduction in the size of the required holdover capacitor required for a desired holdover time improves volumetric efficiency of the off line switcher. This arrangement further improves efficiency of the DC-to-DC converter and decreases stress on its components by narrowing the input voltage range requirement.

Abstract: A pulse width modulated (PWM) inverter is controlled by repetitively changing or dithering desired output currents for the inverter to ensure that it is unable to settle into zero states which result in lack of torque control when the inverter is used to control an AC motor. Dithering is performed by algebraically combining dither values with the desired output currents to generate reference output currents outside a hysteresis band used to control the inverter. Since the reference output currents are outside the hysteresis band, zero states are avoided. Dithering is performed by repetitively adding and subtracting first and second dither values form the desired output currents; or, repetitively adding a first dither value, adding a zero dither value and subtracting a second dither value form the desired output currents. The dither value can be approximately equal to half the hysteresis band, or approximately equal to or greater than half the hysteresis band.

Abstract: An engine-driven power generating system having a bridge circuit section in which low-frequency switching elements are driven alternately by low-frequency drive signals, and high-frequency switching elements driven by high-frequency drive signals during the ON period of the low-frequency switching elements are connected in a bridge network, and an inverter circuit section having a drive signal supply circuit for supplying low-frequency and high-frequency drive signals are each supplied to the low-frequency and high-frequency switching elements that form a pair; the a-c voltage generated by an engine-driven a-c generator is converted into d-c voltage that is in turn converted into a predetermined level of low-frequency a-c voltage; characterized in that an overcurrent detecting circuit for detecting an overcurrent flowing in the bridge circuit section at a level higher than a predetermined level, a drive-signal control circuit that outputs to a drive-signal supply circuit, when the overcurrent detecting circui

Abstract: A voltage regulation circuit for use in "H" bridge circuit applications utilizes feedback networks to provide analog voltage regulation of the output nodes during switching of inductive loads. The regulation of the ouptut nodes during switching of inductive loads eliminates substrate current injection.

Abstract: An electric converter comprising at least three reactive elements (1, 2, 3) connected in series, and a switching device comprising a switching transistor (4) and a diode (5), the switching transistor operating at a high frequency so that it becomes conductive for a fraction of each period of said frequency. The transistor (4) and the diode (5) are connected to the connection points (12, 13) between the reactive elements (1, 2, 3) so that the diode (5) is conductive only when the transistor (4) is non-conductive and so that it is non-conductive each time the transistor (4) becomes conductive. This device is used to control the electric current from a DC power supply to a load.

Abstract: A power generation system is constituted by an induction generator and a converter. An output current waveform of the induction generator is determined by the magnetic flux, speed, winding impedance, DC output voltage, and load of the induction generator. In particular, the output current waveform is changed in accordance with a change in speed (i.e., change in slip). Switching elements in the converter are ON/OFF-controlled in accordance with changes in current waveform, thereby controlling power generation of the induction generator.

Abstract: A circuit and method for controlling an output current balance for parallel driven PWM-type digitalized power inverting units are disclosed in which a feedback control such that rising edge times and falling edge times of a PWM waveformed pulse train signal to be supplied to the parallel driven power inverting units are respectively corrected using independent correction signals is carried out to eliminate a deviation between output currents of the parallel driven power inverting units. The correction of the rising edge times and falling edge times is such that a phase advance correction for the one unit with respect to an offset value delay and a phase retardation correction for the other unit with respect to the offset value delay are carried out so that a delay of an average output current with respect to the PWM waveformed pulse train signal is made constant.

Abstract: A AC to DC power converter unit includes an AC/DC converter section operable to convert an AC input into a plurality of unregulated internal DC outputs and a pair of positive and negative switching DC/DC converter sections connected to said AC/DC converter section and receiving a pair of positive and negative unregulated internal DC outputs therefrom being of a first voltage level and generating a pair of dual positive and negative regulated external DC outputs being of a second voltage level different from said first voltage level.

Abstract: A network for connection between an AC power line and a DC power supply to isolate harmonic currents generated by the DC power supply from the AC power supply, the network employing at least one "resonator", which is connected across the input of a DC power supply, and at least one "reflector", which is connected to couple the input of the DC power supply to an AC power line. Each "resonator," includes the series combination of an inductor and a capacitor. At least some of the "reflectors" include the parallel combination of an inductor and a capacitor.

Abstract: An inverter device achieving a high input power-factor while restraining higher harmonics to be low is provided by a simple circuit structure, in which a pulsating DC voltage supplied through a rectifier is provided through an inductor to a smoothing condenser and to an inverter circuit section connected to output ends of the rectifier to be in parallel therewith, a smoothed DC voltage from the smoothing condenser is supplied through the inductor to the inverter circuit section, and a high frequency voltage is provided out of the device in response to ON and OFF operation of a switching means in the inverter circuit section.

Abstract: A current mirror having an output-to-input current ratio less than unity comprises first and second transistors connected in cascode between an output terminal and a reference terminal, with the base drive of each transistor coupled to the same diode junction. Cascoding plural transistors effectively reduces the base-emitter voltage of the output transistor by the collector-emitter voltage of the other transistor, which normally operates at saturation. The other transistor may be a multi-emitter transistor, with one of the emitters coupled to its base and another of which coupled to the reference terminal. By the addition of a resistor between the emitter-collector connection of the cascoded transistors and the input terminal, the operation of the circuit may be changed from that of a current mirror to a current switch.

Abstract: A high frequency miniaturized switching power supply has a unidirectional spike filter which removes spikes appearing on a feedback signal before such feedback signal is provided to the comparator of the switching power supply. The spike filter removes voltage spikes of one polarity without lengthening the reset time of the comparator in response to a wavefront of the opposite polarity.

Abstract: A power delivery circuit for supplying load current to a load includes a current switch connected on the high potential side of a load. In order to detect a current condition, such as an over-current condition in the load, a current sensing and detection circuit preferably cooperates with the current switch wherein such switch comprises a multicellular device with a plurality of terminals. Such terminals include a first main current terminal connected to a source of high potential, a second main current terminal connecting a majority of device cells to the load, a first auxiliary terminal connected at one end to a minority of device cells so as to provide a current generally proportional to the main device current, and a second auxiliary terminal connected at one end to a majority of device cells.

Abstract: A universal power adapter comprised of a standard IEC three-wire socket, an AC/DC power supply detector circuit, an AC/DC power supply selector circuit, an AC/DC power supply pre-treating circuit, a DC power supply transformer circuit, a feedback and regulating circuit, and a DC output circuit, wherein said standard IEC three-wire socket connects an AC or DC input voltage to said AC/DC power supply selector circuit and said AC/DC power supply pre-treating circuit for converting into a DC voltage via said AC/DC power supply detector circuit, said DC voltage being treated through said DC power supply transformer circuit and said feed back and regulating circuit to provide a DC working voltage for output through an output device.