Abstract: A battery protection circuit for an engine ignition system comprises first and second terminals for connection in series with a discharge circuit of the battery and normally ON switching means connected between said terminals. If the battery voltage falls below a predetermined level, for example, as a result of leaving the headlights on in a parked motor vehicle, incorporating the circuit in its ignition system, the switching means turns OFF and isolates the battery, so as to prevent further discharge of the battery. The switching means can be reset by the user, for example, by means of a signal from a handheld I.R. transmitter on returning to the vehicle, enabling the ignition coil to be energized from the battery and the engine to be started. Thus the circuit can be used to prevent a vehicle battery from going flat when the vehicle is parked.

Abstract: An electric power supply system is provided for an automatic water discharge device for discharging water to flush a basin. An object detector detects a person before the basin. A brightness detector, which consumes less electric power than the object detector, detects a brightness surrounding the basin. An electric power is supplied to the object detector on a power supply cycle so as to intermittently render it operative and to the brightness detector on a brightness detect cycle. The brightness detect cycle is longer than the power supply cycle. After a set time period following disappearance of a person from the basin, the electric power is, on one hand, shut off from the object detector to render it inoperative and, on the other hand, supplied to the brightness detector on the brightness detect cycle immediately after the shut off of electric power to the object detector, to detect a brightness surrounding the basin.

Abstract: A circuit breaker comprises a static switch electrically connected in series with a disconnecting switch having an operating mechanism with a handle to close and open a system of main contacts. A voltage sensor ocmprises an electromagnet with a moving core capable of occupying an active locking position and an inactive unlocking position of the mechanism, respectively in the on state and in the off state of the switch. Opening of the disconnecting switch is inhibited if voltage is present on the output terminals.

Abstract: In order to provide a voltage supply circuit with high efficiency, high control quality and with optimum utilization of the present energy the circuit comprises in combination a switching controller and a longitudinal voltage controller and a static starter circuit is provided, which supplies via a transistor the electronic components of the circuit with energy until a predetermined voltage is attained.

Abstract: Two storage capacitors connected in parallel with a constant current source in a charging mode and connected in series in a second mode to increase output voltage. A comparator senses the amplitude of the output voltage and controls the current supplied to the capacitors in the charging mode to increase or decrease the output voltage to coincide with a predetermined amplitude.

Abstract: Two pulse-width modulated power supplies are synchronized to operate at 180.degree. of phase shift to reduce the peak amplitude of the instantaneous current drawn from the DC input bus. The circuit includes means for disabling the synchronization upon detection of an undervoltage fault condition on the output of either supply. This feature allows frequency programming techniques to be used to provide foldback current limiting for either supply without affecting the operation of the other supply.

Abstract: A multiple outlet receptacle, such as one having four outlets in respective quadrants, is provided with a surge suppression circuit including a metal oxide varistor edgewise between the front and back of the device, other electronic elements, including dual status indicators, connected with an outer ring like contact plate and secured within portions of the insulating housings. Features for compactness and ease of assembly are provided. A pilot light indicator may alternatively be provided in receptacles without a surge suppressor utilizing some of the same components and assembly features.

Abstract: A limiter/clamp circuit is described having a sharp bend in the clamp characeristic and a transition from its linear range to its clamp range that occurs over a desirably small voltage range. The sharp bend is achieved by a feedback loop consisting of plural transistor elements configured in a current "mirror" feedback structure. This circuit is based on achieving an exponential/logarithmic dependence of the voltages and currents in the feedback loop, which serve to control the feedback signal to the base of a 2-transistor clamping device. The circuitry also provides relatively symmetric clamping.

Abstract: A dual mold choke is provided to reduce both differential and common mode electromagnetic interference. Ferrite cores are placed around DC power bus bars providing an inductor limiting differential mode noise and creating a choke reducing common mode noise. The use of E-cores provides a simplified mechanical assembly while providing high levels of noise reduction. An air gap between the center legs of the cores prevents saturation of the choke.

Abstract: In a alternating current power distribution system utilizing load tap changing (LTC) transformers having selectively actuable tap selector switches operable in response to an LTC control, system including circuitry for providing remotely adjustable bias voltage for combining with the LTC control voltage to remotely control any change of the center operating level of the band.

Abstract: A wide dynamic range current source circuit comprising a first current mirror circuit including a first transistor functioning as a first output current path, and a second transistor for receiving a first control voltage and functioning as an input current path for controlling a current flowing in the output current path. The wide dynamic range current source circuit further comprises a second current mirror circuit including a third transistor functioning as a second output current path bypassing the input current path of the first current mirror circuit, and a fourth transistor for receiving a second control voltage different from the first control voltage and controlling a current of the second output current path. The second current mirror circuit controls current flow in the first mirror circuit such that this current flow is larger than a current flowing during a non-linear operation of the first current mirror circuit.

Abstract: In broadband space-division switching networks a multi-layer p.c. board is used for wiring the switching matrices of adjacent switching stages. In case of a plurality of links between the switching matrices a corresponding number of layers of the p.c. board can be provided. The connection of the individual layers of the p.c. board requires much expenditure in point of manufacturing engineering.This expenditure can be reduced in a surprisingly simple manner, when a canonical linkage in a p.c. board is introduced such, that link sections of the switching matrix are fanned out into groups onto a layer of the p.c. board and combined again. By dividing the links into sections, requirements as regards equal line length, reduction of space required and replacement in case of defects can be met in a simple manner.

Abstract: The present invention is directed to circuitry which uses a reference voltage and a reference current to produce a resistance which stays essentially constant even when the temperature of the device varies. The circuitry of a preferred embodiment consists of a resistor and a n-channel FET. The source of the FET is connected to ground, and the drain is connected to one terminal of the resistor. The other terminal of the resistor is connected to a reference current source and to the noninverting terminal of an operation amplifier. The inverting terminal of the operational amplifier is connected to a reference voltage. The output of the operational amplifier is connected to the gate of the FET. The value of the resistor is chosen such that the voltage drop across the FET (I.e., V.sub.ds) is small so that the FET operates in the linear region. A resistive element is composed of the resistor and the on-resistance of the FET.

Abstract: A direct current power supply device which generates an alarm signal when a power failure occurs in an alternating current power supply connected as an input to the device. A power failure detector circuit is connected at the input of the device and signals the failure of the AC power supply. In order to compensate for different time delays in the fall of the DC output due to varying loads at the output of the device, a reset signal generating circuit is used which is controllable in accordance with the size of the load. The circuit receives as an input, a signal identifying a power failure from the power failure detector circuit and a signal identifying the load current value from a load current value detector circuit, connected between the load and the AC/DC converter. The reset signal generating circuit, using analog or digital components, will generate a reset signal at a timing determined by the size of the load.

Abstract: An electric generating system is provided and consists of a generator mechanically operated by a starter motor in which the generator operates a battery charger to recharge a battery that can operate the starter motor when the starter motor is disengaged from a remote power source.

Abstract: A current-sensing rectifier for current rectification and measurement applications is described. The current-sensing rectifier comprises a current-sensing device for rectifying the current in a selected circuit branch and an active-sense comparison circuit to measure the sense current provided by the current-sensing device. The current-sensing device and active measurement circuit are operated such that the current-sensing device rectifies the current of a selected circuit branch. No negative voltage supplies are required for rectification or for the measurement of the branch current. Further embodiments of the present invention include sample-and-hold circuits which sample the value of the rectified current during an ON-period of operation and maintain the sampled value during a subsequent OFF-period.

Abstract: A vectorial neutral is provided in a delta power source. The neutral voltage point is provided by auto-transformers which correct and maintain a near constant voltage in the presence of load or bias currents. With a centered referenced voltage established, full wave rectification of a delta power source is possible.

Abstract: The RICTPD device is designed to protect integrated circuits with external leads on the sides of the case from electrical transients caused by lightning, switching inductive loads such as electrical motors, or other sources. The RICTPD is usually used when a particular IC is identified as most likely to fail in a system. The RICTPD comprises a casing which is slightly larger than the IC casing, and has metal legs in the form of springs which provide a friction fit on the legs of the IC. The inside top of the device case has a plurality of transient protection devices (TPDs) built in between a metal ground plane and the metal legs. A grounding strap is attached from a ground terminal which is part of the ground plane on the device to an available ground on the circuit board. The TPDs may consist of metal oxide varistors, surgectors or zener diodes made to be aligned with the IC legs and the ground plane of the device. The device may be installed over the IC by a press fit.

Abstract: A fault tolerant power supply comprises a first rectifier and a second rectifier with a boost circuit for correcting line current harmonics. The second rectifier, the boost circuit and output diodes are connected in parallel with the first rectifier. A capacitor circuit is charged through the second rectifier and boost converter when a 240 volt line input is present, but the circuit is charged through the first rectifier when a 120 volt line input is present. With failure of the boost converter circuit or with removal of the boost converter circuit from the system, the capacitor circuit is charged through the first rectifier.

Abstract: An apparatus and method is disclosed for controlling a load capable of functioning for a predetermined purpose in response to a predetermined amount of electrical power. The load can be operated from either an AC or DC source using a two-wire connection. The predetermined amount of electrical power is applied to the load if a sensor senses a triggering event. During the time period when a triggering event is sensed, power is cycled on and off to the load in order to enable continuous monitoring of the trigger event. During most of the time period, the sensor receives power to maintain its operations from a storage circuit. If the charge in a capacitor decreases to a predetermined value, the predetermined amount of electrical power is removed from the load momentarily to allow replenishment of the capacitor charge.