Abstract: A switched power converter for a recreational vehicle includes a housing and a switched power supply. The switched power supply has a switch and at least one energy storage component, the switch controlling the supply of power to the energy storage component. The output of the energy storage component is a regulated DC output voltage. A controller generates a switching control signal for controlling the state of said switch. A protection circuit is connected to the controller for protecting the switched power supply from damage resulting when a reverse battery connection is made. The circuit also includes a controller for controlling the pulse-width of the control signals input to the switch. A fan may be provided on the housing which is selectively enabled to move cooling air over the switched power supply only when a detected temperature exceeds a threshold level. The controller may be disabled when an ambient temperature exceeds a threshold level.

Abstract: An emergency power system is connected between an AC voltage source and a load. The emergency power system ensures a stable voltage on the output, even if the AC voltage received from the AC voltage source is irregular or is interrupted briefly. The emergency power system includes an AC/DC converter coupled between the load terminals and an AC regulator positioned between the AC voltage source and the load. The AC/DC converter is coupled to a chargeable battery and serves as a charging rectifier for the battery in normal operation and as an inverter in emergency operation, the battery voltage being converted to AC voltage on the output of the emergency power system. The AC regulator is built as a controllable current generator supplying on its output an AC current which is in phase with the AC voltage received from the AC voltage source. Irrespective of the energy direction through it, the AC/DC converter maintains the predetermined AC voltage (V.sub.

Abstract: With direct current/direct current converters of modern construction, which can be operated at frequencies as high as 500 kHz, the number of secondary windings that are necessary decreases with simultaneously high currents, so the necessary voltage can be generated by a single winding, or even by less than one winding. A push-pull converter exhibits, for example, a transformer with a center limb (19) and two outer limbs, and that contains on the secondary side two coils (29, 30), each of which consists of a single, complete winding with one center tap (B, E) each. These coils are placed around the center limb (19) in such a way that the two center taps (B, E) come to be located opposite each other in two openings (18) between the outer limbs.

Abstract: Methods, circuits, and kits for converting battery powered smoke detectors to AC power include a power converter which converts standard household AC voltage to a DC voltage suitable for use by a battery powered smoke detector and a battery clip connector for connecting the power converter to the battery clips of a battery powered smoke detector. According to one embodiment of the invention, a light emitting diode is coupled to the battery clip connector to indicate the presence or absence of DC voltage at the smoke detector. According to another embodiment of the invention, several battery powered smoke detectors are coupled to a single power converter. In yet another embodiment of the invention, several battery powered smoke detectors are provided with an AC power supply having an automatic battery back-up power supply. Preferred aspects of the invention include: providing the battery backed-up AC power supply with a battery tester and providing fuses for each smoke detector and for the battery.

Abstract: A high voltage power supply (40) having a plurality of high voltage generators (50a, 50b, . . . 50j) that produce a controlled current in a load (24) having a capacitive component. Each high voltage generator consists of a pulsewidth-modulated (PWM) inverter, a high voltage transformer, and a high voltage full bridge rectifier. The high voltage generators are divided into three groups: Group I, Group II, and Group III. During a driving mode of power supply operation, the Group I, Group II, and Group III high voltage generators produce an output voltage (V.sub.gen) from the power supply which exceeds a voltage (V.sub.c) across the capacitive component of the load, causing the current in the load to increase. When the current in the load reaches a desired value, the power supply enters a tracking mode of operation. During the tracking mode, the Group I and Group II high voltage generators produce an output voltage (V.sub.gen) from the power supply which equals the voltage (V.sub.

Abstract: The present invention relates to a high power factor power supply system of high efficiency which is small in size and light in weight. The invention operates by setting the input power factor to 1 and by controlling a resonant converter. The power factor power supply system according to this invention includes: a full wave rectifying means for rectifying an alternating signal; a voltage dividing means for dividing a rectified signal; a capacitor connected in parallel to the voltage dividing means; an inductor connected to the full wave rectifying means; switching means for controlling a supply of current flowing in the inductor; a resonant circuit portion formed of the inductor and capacitor and connected to the switching means; an output circuit for receiving a signal of the resonant circuit portion, rectifying and then transmitting the signal to a load; and a controlling circuit for providing a switching controlling signal to the switching means.

Abstract: A magnetic device, a method of manufacturing the magnetic device and a DC/DC converter employing the magnetic device.

Abstract: A switched power converter for a recreational vehicle includes a housing and a switched power supply. The switched power supply has a switch and at least one energy storage component, the switch controlling the supply of power to the energy storage component. The output of the energy storage component is a regulated DC output voltage. A controller generates a switching control signal for controlling the state of said switch. A protection circuit is connected to the controller for protecting the switched power supply from damage resulting when a reverse battery connection is made. The circuit also includes a controller for controlling the pulse-width of the control signals input to the switch. A fan may be provided on the housing which is selectively enabled to move cooling air over the switched power supply only when a detected temperature exceeds a threshold level. The controller may be disabled when an ambient temperature exceeds a threshold level.

Abstract: A filter module for a frequency converter comprises a filter circuit housed in a casing adapted for connection to the converter. The filter module includes an input filter and an output filter so arranged that input terminals for connection to the AC line voltage and output terminals for connection to an electric motor are disposed on a common side of the casing and so that the connections between the frequency converter and the filter module are disposed on a side of the casing which in use faces the converter.

Abstract: A power converter with a self synchronized synchronous rectifier includes one or two drive windings to provide positive drive to the control electrodes of the controlled switches (FETs) of a self synchronized synchronous rectifier. The polarities of these windings are selected so that the switched devices are driven appropriately to rectify the periodic signal output of the secondary winding of the power transformer of the converter. In some arrangements one or two drive windings are included as extra windings in the power transformer and connected to provide the proper polarity drive signals. The turn ratios of the drive windings to the other windings are selected to provide the proper gate drive signal levels. In an alternative arrangement a separate drive transformer may be provided to supply the gate drive signals.

Abstract: A power switching circuit module includes two power rails coupling independent power supplies to the input of a DC controller and test circuits to detect latent faults in power mixing devices included in the circuit.

Abstract: A power supply for producing a regulated dc output from an ac primary input incorporates a convention rectifying and filtering circuitry feeding a switching circuit for providing a high frequency, substantially rectangular voltage waveform to a high frequency transformer. The output of the transformer is provided to a synchronous buck converter having a grounded line and an ungrounded line, with a first FET switch in the ungrounded line and a second FET switch connected from the output of the first FET switch to the grounded line. A controller in the synchronous buck converter switches the FETs according to the input voltage waveform to achieve rectification. In another aspect, two FETs are placed in opposite polarity in the ungrounded line and switched together, and the controller also alters the duty cycle of the switching in accordance with the magnitude of a regulated output produced from the output of the synchronous buck converter, to achieve precise regulation.

Abstract: A power supply apparatus having an AC-DC converter includes a transformer, an AC-DC converter, a power supply controller, a push switch, and a relay and a relay contact. The relay is connected to an AC power supply voltage input side of the primary coil of the transformer, turned on to apply the AC power supply voltage to the primary coil of the transformer when the push switch designates to start applying the DC power supply voltage to the load, and turned off to stop applying the AC power supply voltage to the primary coil of the transformer when the push switch designates to stop applying the DC power supply voltage to the load.

Abstract: A high-frequency high-voltage generator is provided for x-ray technology that automatically adapts to all load instances and to the coupling network. The inverter is driven dependent on the zero-axis crossing in a series resonant circuit. The capacitor of this series resonant circuit is bridged by an inductance, forming a parallel branch and the control signal for the inverter is acquired from the time delay between the zero-axis crossings in the series resonant circuit in the parallel branch.

Abstract: A switching power supply supplies a regulated output voltage for an electronic apparatus in industrial or commercial use and suppresses generation of a spike voltage and a spike current due to a transformer, and a recovery voltage of a rectifying diode due to switching and it results in reduction of noise interference and power loss. A series connection of a first switching means and a second switching means repeating on/off action alternately is connected to a d-c source. A series connection of a first capacitor and a primary winding of a transformer is connected in parallel with the second switching means. An induced voltage in a secondary winding is supplied to an output through a rectifying/filtering means. A series resonance current in a closed circuit comprising the first capacitor and a leakage inductance suppresses spike voltage, spike current, and recovery voltage of the rectifying diode.

Abstract: Circuit arrangements and methods are disclosed for providing trickle voltages and currents when a main power supply is unavailable or, alternatively, for providing auxiliary power. In one embodiment, a trickle power supply consists of a bilaterally conducting semiconductor diode device such as a SIDAC receiving an unregulated DC input voltage through a resistor. The SIDAC is contemplated to have a specified breakover voltage V.sub.bo and current carrying capability chosen according to designer preference. A first capacitor is coupled between the SIDAC and a primary side of a step-down pulse transformer providing a specified reduction in voltage from a secondary side relative to the voltage applied to the primary side. The resistor, the first capacitor, and the SIDAC together form a modified RC resonant circuit oscillation characteristic. When the unregulated DC input voltage is applied, the first capacitor will charge up to the breakover voltage V.sub.

Abstract: In a switching power supply, electric current is supplied through a switching device to a load located away from the switching power supply. The electric current at the load is detected by a remote detecting device at remote detecting terminals. The remote detecting device includes a differential amplifier and a comparator connected to an output terminal of the differential amplifier. The comparator compares an output voltage of the differential amplifier with a reference voltage and outputs an alarm signal when the output voltage of the differential amplifier is lower than the reference voltage. A control device is connected to the switching device, the output terminal of the remote detecting device and a first reference voltage supply device. The control device changes ON-OFF duty ratio of the switching device by comparing the output voltage of the differential amplifier with the first reference voltage to control an output voltage of the switching device at a predetermined value.

Abstract: A switching power supply supplies a regulated output voltage and suppresses spike voltage and spike current generated by a switching action of transformers, and suppresses switching frequency drift due to load variation. Output stability of multi-output design is improved and recovery of rectifying diodes by a current resonance are suppressed. A reduction of noise interference to electronic equipments and power loss in the switching power supply itself results. A series connection of a primary winding of a first transformer and a first switching means, which repeats an on/off action is connected across a d-c power source. A series connection of a second switching means, which repeats an on/off action alternately with the first switching means, and a first capacitor is connected in parallel with the primary winding of the first transformer. A series connection of a primary winding of the second transformer and a second capacitor is connected in parallel with the second switching means.

Abstract: A device for operating a gas discharge lamp is disclosed which includes a voltage transformer preferably an inverse transformer, to whose output a bridge circuit is connected, with the lamp being disposed in the diagonal of the bridge. A component disposed in the vicinity of lamp and able to carry an electrical potential is arranged in such a manner that an electrical field is able to develop between the lamp and the component. The component is connected with that terminal at the output of the voltage transformer at which the potential is positive relative to that at the other terminal.

Abstract: Disclosed is a switching power source device for supplying a DC stabilized voltage to industrial or household electronic appliances. The power source device can restrict a change in the switching frequency due to the change in load so that low noise and high efficiency can be realized. The power source device includes a first rectifying and smoothing circuit and a second rectifying and smoothing circuit. The first rectifying and smoothing circuit includes a rectifying diode and a smoothing capacitor. The second rectifying and smoothing circuit includes a rectifying diode and a smoothing capacitor.

Abstract: A rectifier for a DC/DC converter includes first and second FETs, first and second capacitors, and first and second resistors. The first FET is connected in series with the secondary winding of a main transformer of the DC/DC converter. The second FET is connected in parallel with the series circuit constituted by the secondary winding of the main transformer and the first FET. The first and second capacitors are respectively connected between the gate of the first FET and the drain of the second FET and between the gate of the second FET and the drain of the first FET. The first and second resistors are respectively connected between the gate and source of the first FET and between the gate and source of the second FET.

Abstract: A switching power supply circuit includes a DC/DC converter, a control circuit, a first auxiliary power supply circuit, and a second auxiliary power supply circuit. The DC/DC converter has a transistor for switching a DC input voltage. The control circuit controls the ON/OFF time of the transistor to keep a DC output voltage from the DC/DC converter constant. The first auxiliary power supply circuit supplies power to the control circuit during a normal switching operation period of the transistor. The second auxiliary power supply circuit supplies power to the control circuit when a DC input voltage is applied to the switching power supply circuit. The second auxiliary power supply circuit is controlled by an output voltage from the first auxiliary power supply circuit to stop the supply of power.

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 semiconductor rectifying diode includes a first semiconductor region of one conductivity type, a plurality of third semiconductor regions of the other conductivity type provided on one surface of said first semiconductor region to be spaced a distance W, and a main electrode provided on said one main surface to in ohmic contact with said first semiconductor region and in contact with said third semiconductor regions through the Schottky barrier. To reduce reverse leakage current a relation of 2wo<W.ltoreq.3D is satisfied, where D is the depth of said third semiconductor regions and wo is the width of a depletion layer spread to said first semiconductor region by a diffusion potential of the pn junction formed between said first semiconductor region and said third semiconductor region.

Abstract: An a-c/d-c microwave oven adapted to be connected to an a-c and/or d-c power source. The oven has an inverter for converting d-c power to a-c power to feed power to a magnetron generating high-frequency energy via a transformer. Input from the d-c and a-c power sources is selectively fed to the magnetron. A first primary winding is fed commercial a-c power. A second primary winding is fed on a-c voltage from the inverter. A secondary winding connecting to the magnetron is wound on the transformer. A predetermined voltage is adjusted in the secondary winding of the transformer by adjusting the frequency of the a-c voltage from the inverter at a higher level than the commercial a-c power, which is fed to the second primary winding.

Abstract: In a regulated power supply, particularly a pulse-width-modulated supply, the on-off control is located in the feedback path between the supply output terminal and the pulse-width-modulator. Transformer coupled polling pulses sense both the state of the on-off control and the magnitude of the feedback error signal.

Abstract: A voltage-compliant power converter module which converts power from an input source for delivery to a load, the load being external to the voltage-compliant converter module and including an external filter capacitance of value Ce for providing ripple filtering of the load voltage delivered to the load, the load being connected to the voltage-compliant converter module via load interconnections external to the voltage-compliant power converter module, the load interconnections being characterized by a total parasitic load inductance of value L1. The converter module includes input terminations for connection to the input source and output terminations for connection to the load interconnections. Switching power conversion circuitry is connected to receive input power via the input terminations from the input source, the power conversion circuitry including one or more switching devices, the switching devices delivering a pulsating voltage waveform at switching frequencies within a nominal operating range.

Abstract: An enhancement-mode converter module, which converts power from an input source for delivery to a load in a series of quantized energy transfer cycles, includes a zero-current switching converter, an enhancement-mode controller, an an input-output port for carrying synchronizing information to and from an external synchronizing bus. The enhancement mode controller adjusts the frequency at which energy transfer cycles are triggered in the zero-current switching converter to be the greater of a first frequency, which will regulate the load voltage to a setpoint voltage, Vsp, characteristic of the enhancement-mode controller, or a second frequency, which is indicated by an input delivered to the input-output port.

Abstract: A high dynamic performance, DC-DC converter system with time sharing cont is described, comprising at least one main control circuit loop for a direct output voltage and at least one further circuit loop for a direct output average current which is internal to the main control loop, the voltage and current loops acting onto two autonomous circuit loops having first order transfer functions.

Abstract: A power supply for converting a variable DC input potential (12) to a regulated DC output potential in accordance with the invention includes a plurality of DC to DC converters (300), each converter operating in response to a DC input potential having an operating range, having an input for receiving a DC input potential which is variable in magnitude, and an output for producing the DC output potential, the outputs of the converters being coupled together; a variable voltage divider (18) having an input coupled to the variable input potential, a plurality of connected stages (100) coupled to the input potential, at least one control signal applied to the variable voltage divider for controlling a number of stages across which the variable input potential is dropped; a switching circuit (200), coupled between the variable voltage divider and the plurality of DC to DC converters, responsive to at least one switching control signal, for coupling an output potential developed by at least one of the stages to at

Abstract: A constant dc current supplying circuit comprises a dc voltage supply, an inverter providing an ac voltage from said dc voltage, and an ac-to-dc converter providing a dc current from the inverter output and supplying the resulting dc current to a load. The inverter includes a switching element driven to turn on and off in order to repetitively interrupt the dc voltage for producing the dc current of which level is determined by on-off time ratio of the switching element. A comparator is included to compare a level of the dc current supplied to the load with a predetermined reference level so as to provide a first output and a second output when the dc current level is below and above the reference level. Also included in the circuit is a feedback controller which generates first and second feedback control signals, respectively in response to the first and second outputs from the comparator.

Abstract: The switching power supply has high output power, high efficiency and fixed or variable output voltage. The input voltage may be AC or DC. Preferably, the input current is constant. Smallest possible peak currents of switches result in best possible line and component utilizations at any time.In one embodiment, a first converter has an output for converting DC input voltage into a base voltage. A first capacitor is coupled between the DC input voltage and first converter output for storing the base voltage. A second converter is coupled to the first converter output for determining the output voltage. A second capacitor filters the output voltage. Both converters are referenced to ground. A diode applies the DC input voltage to the output.

Abstract: A DC-DC converter comprises a switching element having a rise time t.sub.on and a fall time t.sub.off ; a control device for controlling the switching operation of the switching element; a transformer having a primary winding and a secondary winding, the primary winding being connected to a DC power source through the switching element, and having an open inductance L.sub.M ; an inductance coil having an inductance L connected to the secondary winding of the transformer; and a rectifying device for rectifying the output from the secondary winding of the transformer; assuming that the voltage applied to the primary winding of the transformer is E, the load current flowing through the transformer is I.sub.D, and the sum of the stray capacitance of the switching element and the distributed capacity of the windings of the transformer is C1, the following relational expressions being established:L>(E/I.sub.D)T.sub.onandL.sub.M >t.sub.off.sup.2 /.pi..sup.

Abstract: A high frequency transformer is made on a magnetic circuit which can be of a generally square shape. The secondary windings are made on printed circuit plates, separated by insulators and traversed perpendicularly by the core or cores of the magnetic circuit. The primary winding can be wound directly on such a core. The transformer is applicable in particular to high frequency very high voltage power supplies, in particular of the type termed "flyback" power supplies.

Abstract: A conversion circuit is provided which includes a negative temperature coefficient resistance between a rectifier and a storage capacitor to limit inrush current when power is applied to the circuit after a power interruption of a relatively long duration. When power is resumed after a short term power interruption and the resistance of the negative temperature coefficient resistance is still low, inrush current is limited by disconnecting a load from the conversion circuit immediately upon the occurrence of the power interruption to maintain the charge on the storage capacitor for the duration of the interruption. A boost regulator unit is provied between the negative temperature coefficient resistance and the storage capacitor to provide a regulated direct current potential across the capacitor which is not responsive to input power variations.

Abstract: Digital equipment such as an electronic computer comprises a memory unit, an operation unit and a processing unit. In the digital equipment, a short-time service interruption compensation means in compact and simple constitution is installed within a power conversion circuit, and a timer circuit to halt each of the equipment in case of service interruption for a long time is provided as a runaway preventing safety means for the equipment. A power conversion device of the digital equipment is composed of a rectifier circuit which rectifies the commercial power source voltage, a battery as a service interruption compensation means which performs floating charge of the rectifier circuit output and discharges the charged DC power source so as to treat service interruption of the commercial power source, and a DC to DC conversion circuit which converts DC current from the rectifier circuit at normal state or from the battery during service interruption in DC-DC conversion.

Abstract: The invention relates to switching power supplies receiving AC line voltage or DC voltage, particularly for highly efficient regulators operating at high switching frequency. The power supplies contain at least two switches being switched independently of each other; their individual parts can even oscillate autonomously. The energy is stored in at least one capacitor charged by high frequency current pulses. The discharging is independent of the user and also when the output resistance of the line is high so that the output ripple is very low, no minimum load is required and the power failure protection is inherent. The input current of the power supply is uninterrupted. Furthermore, there are no surge currents and any voltage spikes are eliminated; no snubbers are required. EMI/RFI are extremely low. Thyristors and triacs can be employed as they can be turned off by one of the remaining switches. The switching power is actually also an operative power amplifier with an extremely short response time.

Abstract: A high frequency switching regulator drives plural loads by way of an output transformer. The transformer includes plural secondary windings connected to plural loads. One of the secondary windings is connected to a main output channel including a circuit for maintaining the current in the main channel above a predetermined minimum required for proper voltage regulation of the other channels. The circuit includes a current transformer in a line of the main channel. The current transformer contains a saturating core that saturates in response to a main channel current slightly above the predetermined minimum main channel current. An impedance responsive to current in the current transformer loads the main channel so that the main channel current is never less than the predetermined value regardless of the impedance between load terminals of the main channel. This assures proper inverter operation to maintain full voltage regulation of the other output channels.

Abstract: In a signal transmission system whose transmission line (16) is connected to a line side component (66, 68) of a respective transmitter (12) and receiver (14) and is electrically isolated from the operating side, the line side component (66, 68) of the respective transmitter (12) and receiver (14) is powered from the operating side over through an isolating DC/DC-transducer (10).

Abstract: A power supply circuit includes a battery power source connected by a switch to the input of a DC to DC converter. The output of the DC to DC converter is connected to a filter capacitor and a load. A crow-bar is connected to the input and the output of the DC to DC converter. The crow-bar shorts the output to ground to discharge the capacitor when the voltage at the input drops to a predetermined value.

Abstract: A DC to AC converter has a linear output amplifier for simplification and for reducing distortion and output noise. A DC to DC converter or converters provides outputs regulated to have small predetermined voltage differentials to the supply output. This insures a high overall efficiency. A rectifier-filter added to the input converts the unit to an AC to AC power supply.

Abstract: A dual regulated DC power supply produces an output voltage which is the sum of a variable DC control voltage and a floating DC voltage. The control voltage, generated by a first differential amplifier having an inverted input coupled to the power supply output through a feedback scaling circuit, varies in inverse relation to the change in power supply output voltage. The floating DC voltage is produced by isolating, rectifying and filtering the output of an oscillator having a peak voltage controlled by an applied bias voltage. The applied bias voltage is generated by a second differential amplifier coupled to compare the control voltage with a selected reference voltage so that a change in control voltage causes a change in the floating voltage. The control voltage changes rapidly in compensating response to transient changes in power supply voltage while the floating voltage changes more slowly in compensating response to output voltage changes due to sustained load swings.

Abstract: This on/off power detector includes an input connected directly to a power source and input connected to the power source through a switch. The detector compares voltages on the two inputs to produce an output signal when the voltage on the switched input drops a predetermined amount below the voltage on the unswitched input, which is indicative of the switch being open. The detector is strobed on and off and only compares the input voltages to provide the output signal when it is in its strobed on condition.

Abstract: The power supply converts alternating current voltage to a direct current voltage which is in turn converted to a pulse width modulated voltage. A circuit arrangement is provided responsive to the pulse width modulated voltage to produce N output direct current voltages each having a different predetermined value, where N is an integer greater than one. A feedback circuit is provided between the circuit arrangement and the circuit providing the pulse width modulated voltage to provide a substantially constant value for the N output voltages when a varying load is presented to the power supply. A current transformer arrangement is coupled in series in the feedback circuit to provide wide bandwidth and low droop without oscillation for the power supply when the power supply is subjected to a step load (a step from no-load up to full-load).

Abstract: Fuel injection apparatus including a power converter for generating a stable, high voltage DC signal for powering the fuel injectors. The power converter is connected to a voltage source such as a vehicle battery. The power converter includes a DC-DC converter and a feedback-stabilized converter control circuit. The converter control circuit adjusts the operation of the DC-DC converter in a direction to counteract changes in output voltage caused by battery voltage variations. The high voltage DC signal is applied to each injector through one or more solid state switches. Since the signal used to power the fuel injectors is substantially constant regardless of normal battery voltage variations, the injector pull-in time is substantially constant. Moreover, the use of a high voltage power signal enables low current injectors to be used. The low injector current results in low power dissipation by the solid state switches which operate the injectors.

Abstract: A DC-DC converter converts an incoming unstabilized D.C. voltage to three stabilized output D.C. voltages. The converter contains two chopper stages (1, 2) with associated transformers, rectifiers (3, 4, 17a, 17b) and smoothing filters (5, 6, 18). The two chopper stages give a first and a second pulse-formed output voltage (U.sub.a and U.sub.b) which are regulated by shifting the leading edge of the pulses in the first output voltage (U.sub.a), while the second output voltage (U.sub.b) is regulated by shifting the trailing edge of the pulses. Two output voltages (U.sub.1, U.sub.2) are obtained after recitfying and smoothing. The third output voltage is obtained by connecting in parallel the outputs of two full-wave rectifiers (17a, 17b) which are magnetically coupled to the outputs of the two chopper steps, and by connecting a smoothing filter (18) to the common output of both full wave rectifiers. Regulation of the third output voltage (U.sub.

Abstract: An acoustic fuel injector system comprises a DC-to-DC converter (14) for supplying a regulated voltage to a frequency controlled oscillator (16) which drives the injector valve (18) or valves. The converter comprises a flyback oscillator (28) including a switching transistor (32) and a transformer (34, 36) for applying rectified current pulses of variable amplitude and occurrence rate to an output capacitor (42). A variable impedance device (50) in the input circuit to the flyback oscillator is controlled by a feedback signal (68) from the output circuit (30) to vary the cycle rate of the flyback oscillator to maintain output voltage at a desired value. The feedback signal is coupled to the oscillator control circuit input to effect a variable regulated output voltage which is relatively high upon injector turn-on but decays to a lower operating level thereafter.

Abstract: Apparatus is disclosed for controlling the regulating inductance of a power supply by applying across a control winding mounted on the same core a voltage having a volt-second product proportional to the difference between a desired output voltage and the actual output voltage so that the frequency of response is the same under all operating conditions. In a preferred form, the apparatus is incorporated in a power supply having a source of DC pulses that are rectified to produce the output voltage and the volt-second product of the voltage applied across the control winding is proportional to the difference between the detected value of said pulses and a control voltage that is related to the difference between the actual output voltage and the desired value.

Abstract: A converter adapted to be mounted within an opening in a wall of a recreational vehicle comprising a receptacle adapted to be received within the opening and an openable cover plate attached to the receptacle to provide access to the interior of the receptacle. A base mounting plate is mounted in the receptacle and a plurality of circuit elements, including a step-down transformer, is mounted on the base mounting plate. Ventilation air is provided through vent openings in the cover plate. By utilizing high frequency alternating current, transformer size is reduced and transformer hum is eliminated.

Abstract: A low ripple high voltage power supply is disclosed for use in a dental X-ray system, utilizing a rectifier and regulator circuit to provide a low voltage regulated DC signal, a DC-AC converter for providing a high frequency chopped power signal suitable for efficient transformation to a high voltage, followed by a multiplier for generating the final high voltage signal to be applied to the X-ray tube. A high frequency clock circuit is used for driving the converter and also for controlling logic circuitry used to develop the regulator control signals. Both a voltage and a current control loop are utilized in the regulator control, and the tube anode current and filament current are controlled as a function of sensed anode current.