Abstract: An improved voltage reference circuit is shown for use in analog integrated circuits including A/D and D/A converters. The voltage reference circuit comprises an operational amplifier having an non-inverting terminal connected to a capacitor. The inverting terminal of the op amp is connected to the op amp output terminal. The output terminal provides a constant reference voltage which is a function of the voltage charged in the capacitor. The capacitor includes a floating gate, an isolating layer, and a controlling gate which is used to charge (program) the capacitor to a fixed voltage. The capacitor structure is such that its charge is maintained constant over time independent of any temperature change. As a result, the voltage reference circuit prevents fluctuations in the output reference voltage throughout its operating period.

Abstract: A current mirror constant current source circuit includes a first current mirror circuit constituted by first and second source-grounded n-channel MOS transistors connected to form a current mirror. A source-drain path of the first MOS transistor forms an input current path of the current mirror circuit, and a source-drain path of the second MOS transistor forms an output current path of the current mirror circuit. A current source is connected between a drain of the first MOS transistor and a high voltage supply line. A third n-channel MOS transistor is connected to have a source and a drain connected to a source and a drain of the first MOS transistor, respectively. A gate of the third MOS transistor is connected to the high voltage supply line. The current source includes a second current mirror circuit formed by two MOS transistors such that the source-drain path of one of the two transistors forms an output current path of the second current mirror circuit.

Abstract: A direct current power source circuit has a voltage control power MOS-FET and a back gate control circuit. The voltage control power MOS-FET is connected between an input terminal and an output terminal of the circuit and the back gate control circuit is connected to a back gate of the voltage control power MOS-FET and controls a back gate voltage for causing a parasitic diode between a source and a drain of the power MOS-FET to become a non-conductive state when an input voltage applied to the input terminal becomes a low level. The output of the back gate control circuit is also connected to a voltage dividing circuit which sets an output voltage of the power source circuit. The arrangement enables to prevent a reverse flow of current from the output terminal to the input terminal.

Abstract: The invention is comprised of two inductors wound in series but in opposite directions around a ferrite core, a resistor being connected in parallel with one inductor, and a wire being looped through a ferrite bead and being wound around the other inductor. The invention allows a 60 Hz power signal to pass without excessively interfering with radio frequency signals in excess of 900 MHz and preferably on the order of 1 GHz. The invention is particularly useful in cable television systems, where a power signal and an RF signal are sinultaneously transmitted.

Abstract: A self-regulating Class E/resonant power converter includes a power switching device which is gated on at each transition between negative and positive half cycles of the load current by drive signals generated by a drive circuit, the rate at which the drive signals are generated being controlled by a zero crossing detector which monitors the load current and adjusts the frequency of the drive signals in correspondence with changes in the time between successive negative-to-positive zero crossings of the load current such that the power switching device continues to be switched on at substantially zero voltge, zero slope conditions to maintain the power converter operating at the optimal Class E frequency.

Abstract: A resonant converter, including a transformer for separating a high-voltage (primary) side from a relatively low-voltage (secondary) side, has at least one synchronous rectifier and an auxiliary sense winding coupled to the gate thereof. The input capacitances of the synchronous rectifiers are reflected to the primary side and the secondary side by the square of the ratio of the number of auxiliary sense winding turns to the number of primary andsecondary winding turns, respectively, thereby reducing the required size of the discrete resonant capacitor. In one embodiment, a gate bias voltage approximately equal to the device threshold voltage is applied to the gate of the synchronous rectifiers. The auxiliary sense windings are etched into a conductive film pattern of the secondary windings. The auxiliary sense windings provide nearly identical secondary and gate drive voltages so that the synchronous rectifiers are gated substantially at the zero-voltage crossings of the secondary winding voltages.

Abstract: A high-frequency and high-voltage power supply unit with an internal protecting circuit includes a first DC power supply device, a second DC power supply device, a converting circuit, a sensing/holding circuit, and an amplifying circuit, where the DC power supply device incorporates with the converting circuit to generate high-frequency and high-voltage power to a neon light load. A wire is connected between a core of a third transformer and the sensing/holding circuit, and a pair of discharging tips disposed between the wire and one output terminal, such that when both output terminals disconnect from the load, a discharge occurs on the dischraging tips, causing an impulse which is further fed back to the sensing/holding circuit through the amplying circuit cutting off the operation of the converting circuit.

Abstract: A very high voltage amplifier in which plural cascaded banks of capacitors are switched by optically isolated control switches so as to be charged in parallel from the preceding stage or capacitor bank and to discharge in series to the succeeding stage or capacitor bank in alternating control cycles. The optically isolated control switches are controlled by a logic controller whose power supply is virtually immune to interference from the very high voltage output of the amplifier by the optical isolation provided by the switches, so that a very high voltage amplification ratio may be attained using many capacitor banks in cascade.

Abstract: A zero current/zero voltage resonant DC to DC converter operating at high frequency, utilizes the series/parallel approach to power conversion. A resonant transformer assembly is inserted into either the primary or secondary of the main transformer, to optimize the operating parameters of the converter.

Abstract: An inverter control device that controls a self-commulated inverter connected to an AC power system via a three phase transformer and in so doing suppresses DC magnetization in the three-phase transformer. The device includes a current DC component detecting circuit for detecting the current DC components contained in at least two of the three phase output AC currents of the inverter and a DC magnetization suppressor signal generating circuit for producing two correcting signals from the current DC components. The two correcting signals are used to balance in amount the three voltage DC components contained in the three phase output AC voltage of the inverter, respectively. An output reference correcting circuit is provided to correct two of first output references in accordance with the two correcting signals and output three second references including the two corrected values and one of the first output reference.

Abstract: A battery operated medical instrument that can operate on either rechargeable or non-rechargeable batteries or can be recharged using either a 120 Volt or a 220 Volt outlet.

Abstract: A battery charging system which prevents false switching from a fast charge mode to a trickle charge mode due to low frequency voltage aberration signals. The battery charging system includes a battery voltage analyzer and a plurality of battery charging and conditioning units for charging different types and kinds of nickel cadmium batteries. Firmware in the microprocessor rejects low frequency aberrations permitting a desired voltage signal to be produced which is indicative of the actual battery potential for charge switching purposes.

Abstract: An electronic device, such as a selective call receiver, includes a housing (302) for the electronic device preferably having a rigid member (304) fixedly integrally attached thereto and extending therefrom, the rigid member constructed to cooperatively connect with a rotatable body (308) and to secure the rotatable body (308) to the housing (302) while allowing the rotatable body (308) to rotate about the rigid member (304), a circuit supporting substrate (301) arranged within the housing (302) coupled thereto, and an alerting device (300) for providing a vibratory alert. The alerting device (300) includes coils (320) on the circuit supporting substrate (301) arranged about the rigid member (304), with each coil (322) capable of being selectively energized.

Abstract: This invention consists of a power conversion device wherein a circuit comprising semiconductor power elements and fuses connected in series with these, and feedback diodes connected in antiparallel with said semiconductor power elements is connected as a bridge, the A.C. terminals of said bridge circuit are connected to an A.C. power source, and the D.C. terminals are connected to a D.C. power source provided with a capacitor, characterized in that said feedback diodes are connected in antiparallel with the series circuits of said semiconductor power elements and fuses.By means of the layout described above, the fuses are prevented from melting when a D.C. short-circuit occurs, since the current that flows from the A.C. terminal to the D.C. power source on D.C. short-circuiting flows through a feedback diode or a bypass diode, and not to the fuses.

Abstract: A linear motor comprises: a first module having several aligned permanent magnets separated by gaps of fixed length, the magnets being disposed so that their North and South poles alternate in plane; a second module formed of one or more pairs of U-shaped electromagnets, the electromagnets having parallel legs and being separated from an adjacent electromagnet by a width equal to that of the gaps between the permanent electromagnets disposed on the fixed module, the electromagnet being connected such that when one of the electromagnets is in register with a gap between two permanent magnets, the other is in register with a third permanent magnet; and, a means for supplying the electromagnets with power as a function of the position of the electromagnet, such that each electromagnet; has a given polarity between a first point beyond register with a permanent magnet by a certain distance and a second point before register with a next permanent magnet by a certain distance, has no power supplied between the seco

Abstract: A synchronous rectifier comprising: switch means responsive to a control signal for selectively providing conduction of an applied AC signal, and driver means responsive to the applied AC signal and adapted to provide said control signal in synchronism with the applied AC signal, wherein the rectifier is integratable into VLSI "chip" form.

Abstract: A standby power supply system is provided for supplying normal AC power to a critical load from an AC power source during normal operating conditions, and for supplying emergency AC power to the load during failure of the AC power source. During normal operation, the standby power supply system actively neutralizes undesirable harmonic components in the input current drawn by the load. The standby power supply system includes a power conversion device having a DC side coupled to a back-up power source and an AC side in parallel with the load and the AC source. A harmonic distortion sensor senses a harmonic distortion current component of a load current drawn by the load during normal operating conditions. A controller is responsive to the harmonic distortion sensor for causing the power conversion device to produce a harmonics neutralizing current to substantially neutralize the harmonic distortion current component produced by the load.

Abstract: A precision rectifier system with differential input and differential output includes an input differential V/I converter responsive to a bipolar input signal voltage with respect to an input reference potential for providing a differential current representative of the magnitude of the input signal; a matching output differential V/I converter responsive to an output voltage signal with respect to an output reference potential for providing a differential current representative of the magnitude of the output voltage signal; amplifier means, responsive to a difference between the differential currents of the input and output V/I converters for adjusting the output voltage signal to null the differences between the differential currents; and switching means, responsive to the polarity of the bipolar input signal, for switching the polarity of the differential current representative of the magnitude of the input signal for maintaining a single polarity rectified output voltage signal.

Abstract: A switching regulator operates either in the discontinuous mode or in the continuous mode depending on the magnitude of a load current. A mode detector outputs a mode signal Vg indicative of whether the switching regulator is operating in the discontinuous mode or in the continuous mode. In accordance with the mode signal Vg, an error amplifier selectively operates with a first feedback ratio or a second feedback ratio so as to output an error signal Ver indicative of the variation of an output voltage of the regulator. The error signal Ver is then supplied to a PWM (pulse-width modulation) comparator which in turn outputs a PWM signal in accordance with the error signal. The PWM signal drives a switching transistor to switch an input voltage of the switching regulator.

Abstract: A transformer with a secondary structure formed in a figure 8 pattern. The secondary structure defines two conducting paths which each incorporate a rectifier and each encircle part of the core only once. The conducting paths overlap and cross only in the window region of the core. The design of the secondary structure allows for the mechanical connections to the transformer to be physically separated on opposite ends of the transformer assembly. This structure allows for alleviation of the connector congestion and provides better cooling and also permits shorter connections to the rectifiers.