Abstract: A regulated power supply provides a regulated supply voltage at a preselected level under normal operating conditions. When power demands of the circuitry driven by the supply requires a higher voltage, the supply adapts to supply such a higher voltage. Such a supply can be used with automotive electronic circuitry, and can supply voltages up to approximately the voltage available on an automobile battery when such higher power demands occur. The higher supply voltages remain regulated, and return to normal levels when the extra power requirement is removed.

Abstract: The invention relates to a switch controller system which furnishes a constant output, voltage over a broad input voltage range. The input voltage may here be lower as well as higher than the output voltage. The large control range is realized by a combination of a down converter and an up converter in a power output stage and a common storage choke. The storage choke is advantageously configured as a flat coil in multi-layer technology and includes a coil core. A novel switch controller system is disclosed which links two known converter concepts having different characteristics with one another.

Abstract: Apparatus and methods for AC power regulation primarily intended for inductive loads (e.g., fluorescent lights, motors, etc.) which provides substantial reduction in power consumption while also providing a leading power factor, reduced harmonic distortion, reduced crest factor and reduced noise. The system is self-adjusting for a wide range of loads and can reduce power consumption by 25% in lighting loads while producing minimal reduction in light output. The system utilizes a triac and parallel capacitor bank in series with the load. The triac is turned-on in response to a near-zero differential voltage measured across the Triac and is turned-off near the peak of each AC half cycle by shunting current around the Triac. The capacitor absorbs the inductive turn-off voltage spike caused by the collapsing magnetic field in the ballast at the instant of triac turn-off. This energy in turn provides longer on period for the lamp, thereby permitting more light and increased operating efficiency.

Abstract: A power conversion device including a plurality of bridge connected self-turn-off modules. Each of the self-turn-off modules includes a plurality of self-turn-off devices connected in series and a plurality of first snubber circuits, each including a first series circuit of a first snubber capacitor and a first snubber diode. Each of the first snubber circuits is connected in parallel with one of the self-turn-off devices to form a first parallel circuit, respectively. The self-turn-off module further includes a snubber energy regenerating circuit including a regenerating transformer and a first auxiliary switch connected in series with a primary winding of the regenerating transformer. A secondary winding of the regenerating transformer is adapted for connecting to an outer power source. The self-turn-off module also includes a plurality of first gate circuits, each for driving one of the self-turn-off devices, respectively, and a second gate circuit for driving the first auxiliary switch.

Abstract: In a half-wave rectifier circuit for obtaining an DC voltage output depending on the level of an input signal through half-wave rectification of the input signal, an input voltage from which a DC component is removed by a capacitor is input to a switch circuit. This input voltage includes an offset voltage which is generated by use of the capacitor. The switch circuit outputs a half-wave rectified voltage to a smoothing circuit by switching the input voltage ON and OFF depending on the polarity of the input signal. Under the condition that an input voltage is controlled to OFF state, the switch circuit shows a high impedance viewed from the input side of the smoothing circuit. Therefore, an output voltage of the smoothing circuit is maintained when the switch circuit is in the OFF state. Thereby, the offset voltage generated by the capacitor is eliminated from the output voltage from the smoothing circuit.

Abstract: A circuit is provided for obtaining precise lamp voltage control and for compensating for varying or fluctuating input from an AC voltage source. The lamp is switched on by a switching device such as a triac. When the triac is powered, a simultaneous powering occurs of a second switching device such as an SCR. The SCR produces a scaled down RMS voltage output which closely matches the actual RMS lamp voltage. This second simulated voltage is precisely controlled in a feedback circuit which includes an RMS to DC converter and a feedback controller. The controller compares a converted DC voltage with a reference voltage and generates a firing pulse to the triac which is advanced or delayed so as to compensate for variations in the AC source as manifested by variations in the converted DC signal relative to the reference signal.

Abstract: A power supply which serves to convert an alternating voltage supplied by an electric mains, into a DC voltage, having a rectifier with input terminals for receiving the alternating voltage and output terminals for supplying a pulsating direct voltage. A first capacitor is connected parallel to the output terminals. An inverter has input terminals connected to the first capacitor. A current limiting circuit is connected between one of the rectifier output terminals and an electrode of the first capacitor in order to limit the inrush current occurring when the power supply is switched on. The current limiting circuit includes a parallel connection of a first resistor and a first switching element, with the first switching element being operative to be in an electrically non-conductive state upon switching on of the power supply and to change over to an electrically conductive state some time after the power supply is switched on.

Abstract: A primary control type switching power supply circuit includes a transformer having a primary side and a secondary side, a control circuit generating a control signal based on a detection signal, a circuit for switching a current flowing through the primary side in response to the control signal so as to generate an A.C. voltage on the secondary side, a rectifying and smoothing circuit for rectifying and smoothing the A.C.

Abstract: A buck regulator command charge circuit includes a compensated-gain control signal for compensating for changes in the component values in order to achieve optimal voltage regulation. The compensated-gain control circuit includes an automatic-gain control circuit for generating a variable-gain control signal. The automatic-gain control circuit is formed of a precision rectifier circuit, a filter network, an error amplifier, and an integrator circuit.

Abstract: A voltage regulator regulates the voltage a static VAR compensator (SVC) supplies to a power supply network. An SVC status detector detects the conducting status of the SVC thyristors and generates the measured SVC susceptance in accordance with that conduction status. A calculator calculates a representative voltage, (i.e. the Thevenin equivalent), of the power supply network based on the measured SVC susceptance, measured SVC voltage, and an estimate of the power supply network's equivalent reactance. An ordered susceptance to be provided by the SVC to maintain the SVC voltage at a desired level is predicted based on the calculated voltage. A firing control unit receives the predicted susceptance value and calculates drive signals for controlling thyristors in the SVC. The equivalent reactance is initially estimated, and thereafter, it is modified automatically to track and compensate for large disturbances in the power transmission network.

Abstract: An inverter/converter power supply system that employs pulse-width modulation controlled by an absolute-value representation of a reference wave. A low-frequency wave, such as a 60 hertz sine wave, is precision-rectified which then is the reference input of a pulse-width modulation controller (PWM). The PWM then produces a high-frequency square-wave signal whose pulse width changes as the amplitude of the rectified reference wave changes. The high-frequency square-wave signal is further rectified at an inverter/converter transformer secondary, whose output is filtered through a low-pass filter that removes the high-frequency component while minimizing the stored charge in the filter capacitor(s) to an amount easily drained by a small constant-current load across it. Feedback from the constant-current load to the PWM further adjusts the pulse-width to compensate for load variations and circuit losses.

Abstract: Charge pump structures (100, 110) are disclosed having a reservoir capacitor (40, 86) and a pump capacitor (26, 84) embedded in a switch network. Each of the switches (120) in the network is formed as an MOS transistor having a gate (122) which defines an array of spaced apertures (124) and a plurality of sources (130) and drains (132) each disposed beneath a different one of the apertures.

Abstract: A voltage regulator controller of the types used with a multi-tap voltage regulator transformer having a plurality of tap positions for adjusting an output voltage in discrete tap position steps is provided with a number of control algorithms which are dynamically changed responsive to the measured oil temperature in the transformer. In one embodiment, the voltage regulator controller includes a memory having tap movement control code stored therein for controlling the tap positions in accordance with a plurality of tap position control algorithms, means for measuring the oil temperature of the voltage regulator transformer, means for monitoring the oil temperature within the transformer and, means for selecting one of the tap position control algorithms as being active as a function of the oil temperature.

Abstract: A single stage high frequency push-pull converter with input power factor correction. The boost converter for input power factor correction and the high-frequency push-pull DC/AC inverter are combined into a single stage converter thereby reducing the number of circuit components while at the same time reducing the voltage stress on the high frequency switching transistors of the converter.

Abstract: A threshold voltage generator for a field-effect transistor, being of a type adapted to compensate for variations of the threshold voltage from a nominal value, comprising a first amplifier having a first input connected to a current generator; a second amplifier connected ahead of a second input of the first amplifier and having an input connected to another current generator; and a third amplifier connected after the first amplifier and having an output adapted to produce the value of said threshold voltage.

Abstract: An integratable current source circuit for generating an output current proportional to an input current includes a first transistor of one conduction type, and second, third and fourth transistors of the other conduction type. Each of the transistors has a base, a collector and an emitter. The first transistor has a current amplification being greater than current amplifications of the second, third and fourth transistors. An input terminal feeds an input current, and an output terminal taps an output current. A current source on one hand is connected to a reference potential and on the other hand is connected to the emitter of the first transistor and to the base of the second transistor. The collector of the second transistor is connected to the reference potential and the emitter of the second transistor is coupled to the base of the third transistor and to the base of the fourth transistor. The base of the first transistor is connected to the collector of the third transistor and to the input terminal.

Abstract: A back-bias voltage generating circuit of a semiconductor device having a driving signal generating portion for receiving oscillating signals from an oscillator such as a ring oscillator and generating alternating high and low driving signals, a first pumping portion for charging the input driving signal at one electrode of a pumping capacitor so as to produce a voltage at the other electrode of the pumping capacitor lower than a back-bias voltage, a second pumping portion for charging another input driving signal at one electrode of a second pumping capacitor so as to produce a voltage at the other electrode of the second pumping capacitor lower than a back-bias voltage, a first switching portion being turned on by a voltage higher than a back-bias voltage and connecting the other electrode of the pumping capacitor to a back-bias voltage terminal when the voltage of this electrode is below the back-bias voltage, and a second switching portion being turned on by a voltage higher than a back-bias voltage and c

Abstract: An improved resonant forward dc-to-dc converter circuit includes control circuitry for achieving an optimal power cycle in which the transistor is either supplying current to the load or recovering in a sinusoidal manner, for limiting power loss by controlling the switch turn on time to the time when the switch collector voltage at recovery is at a mimimum, for maintaining an approximately constant turn off time and for providing pulse by pulse current mode control for high loop stability and superior transient response.

Abstract: Switched-mode power supplies in which a series arrangement of a bipolar transistor and a MOS field effect transistor is used are known and referred to as cascode circuits. In these circuits the bipolar transistor is switched (with the MOS field effect transistor) via the emitter instead of with the base. Since the collector current of the bipolar transistor may vary over a large range, the base should be proportionally driven to prevent the bipolar transistor from getting either above or below its normal operating range. By making use of an extra winding on a transformer arranged in series with the cascode circuit, a non-dissipative proportional drive of the base of the bipolar transistor is obtained. The extra winding is coupled to the base via an inductance.

Abstract: In switched-mode power supply circuits the switch is rendered conducting for a longer period (or more frequently), dependent on the load connected to the power supply circuit, so as to ensure that the transformer can transfer enough energy to the secondary side for charging the output capacitor to a sufficient extent. To ensure that the transformer can always supply all energy stored in the transformer to the secondary side, a demagnetizing detection circuit detects the demagnetization of the transformer. If the load decreases (for example, in standby operation) the on-time of the switch is reduced. However, this on-time may achieve a minimum value so that the power supply circuit no longer functions properly. To obtain an efficiently operating power supply circuit, both in normal operation and in a low-load state, the control circuit of the power supply circuit has at least two modes, i.e.