Abstract: Where a computer system PC board has two separate power planes at different voltage levels and a CPU accesses both power planes, a system for detecting when a CPU will short the two power planes and shutting down the power to the lower voltage plane. The contention prevention circuit consists of a voltage level detection circuit having an input connected to the core power plane. The voltage level detection circuit is connected to the input of a shutdown circuit. Upon receipt of a signal from the voltage level detection circuit indicating that the voltage on the core power plane is greater than that provided by the core power supply, the shutdown circuit disables the core power supply.

Abstract: A low voltage battery pack monitoring circuit for a battery powered electronic device is disclosed. The circuit utilizes low battery and power failure set point voltages and first and second comparison circuits to compare voltage across the device battery pack to the set point voltages. If the battery pack output voltage falls below the low battery pack set point voltages, the first comparison circuit sends a signal to a microprocessor causing a low battery indicator light to be actuated. If the battery pack output voltage continues to decrease below the power failure set point voltage, the second comparison circuit includes a comparator which changes output state and turns off selected electronic systems of the device and the device enters a suspend mode. The low battery pack set point voltage value and the power failure set point voltage value are determined using an empirical look up table.

Abstract: Control equipment (CE) for a series capacitor (1) connected into an electric power line (2) has a semiconductor valve (3), which is controllable in both directions, for connection in parallel with the capacitor. An inductor (4) is adapted to form, together with the capacitor, an oscillation circuit in which the semiconductor valve is included. The equipment has control members (PLL, TC) for firing the semiconductor valve for reversal of the capacitor charge and for control of the times (t.sub.p) for the zero crossings of the capacitor voltage (u.sub.C) such that these become substantially equidistant also in the presence of subsynchronous components in the power line current.

Abstract: Circuitry for extending the sustain time of a DC converter power supply in the event of interruption of AC power.

Abstract: A method and an apparatus are provided for stopping a motor-driven pressure generating pump of a system for coating workpieces with atomized liquid coating material in case of an empty material reservoir or a leakage in a material supply from a material reservoir to the pump or from the pump to an atomizer. The pressure and/or the volume flow at the pump outlet and/or the speed of the pump piston or a value dependent thereon are continually measured. The measured values are then converted to electric signals to be input to an electronic analyzer and analyzed therein. If, during operation, the pressure and/or the volume flow drops below a predetermined value and/or the speed of the piston exceeds a predetermined value, the electrically controlled driving connection between motor and pump or the power supply to the pump motor will be cut-off by output signals from the electronic analyzer.

Abstract: A failure detection system detects a failure in a by-pass switch of a power converter. The by-pass switch switches the electric power supply so that electric power is supplied from a standby power source to a load instead of from a power converter. A switch operation circuit turns the by-pass switch on and off. A first current detector detects the inverted output current of the power converter. A second current detector detects the load current flowing through the load. An operational amplifier adds the outputs of the first and second current detectors. A comparator detects a failure of the by-pass switch. If the addition result given by the operational amplifier is outside a predetermined range of values when the switch operation circuit is turned off, the comparator concludes that the by-pass switch has a failure.

Abstract: An electrical distribution system and method has storage battery mechanism of very large equivalent capacitance providing excellent ripple filtering and an ideal path to ground, and filter capacitor mechanism of microfarad size providing DC blocking and limited AC path to ground. The storage battery entity is maintained as to its charge by DC supply which provides regulated DC power in which switching regulation may be involved. The system and method provides dual voltage capability, both DC and AC in which circuit breakers may be ganged for simultaneous tripping, and in which intrinsic DC circuit(s) may be looped to increase current-carrying capability.

Abstract: An electronic device has a host with a card-receiving slot, with the host being capable of receiving and operating low voltage-low current (3.3 volts and no more than 0.12 amp) cards, low voltage-high current cards, high voltage (5 volts)--low current cards, and high voltage-high current cards. The inner end of the slot has a voltage-discriminating first side and an opposite current-discriminating second side. Each side has a switch with an actuator lying at a location that is occupied by a discrimination key portion that is present in one kind of card (low voltage or low current) but not in another kind of card (high voltage or high current). The electronic device has different circuits for energizing or rejecting the types of card sensed by the switches.

Abstract: A power drawing circuit for a two-wire switching unit, the two-wire switching unit including a switching control circuit having its positive voltage input terminal connected in series to a load, the load being connected to one side of a power source.

Abstract: A transformer, typically a miniature transformer, to provide low-voltage power between, usually, 2 to 12 V from a power network has an auxiliary winding (6) inductively coupled to the core (9) of the transformer. A reference signal is provided from the power supply, and a monitoring circuit (32), which includes a difference-forming circuit (16) is coupled to receive (a) a signal from the auxiliary winding (6) and (b) the reference signal, the difference-forming signal providing an output in dependence on the state of magnetization of the core, by evaluating differences in magnetization (.DELTA.B) depending on whether power is being supplied by the transformer, or not. A circuit interruption element (10), typically a transistor, is serially connected between the power supply (1, 2) and the transformer.

Abstract: In a control system for a power transmission and distribution system, a plurality of distributed power supplying and receiving units each including a control unit are provided and connected along a power distribution line. The power supplying and receiving unit function to generate active and reactive powers of fundamental and higher harmonic waves to supply and receive the same to and from the power distribution line. A first central control unit controls the power distribution line and is designed to store information relating to the configuration of the power distribution line, to collect information with regard to instant open and close conditions of respective disconnecting switches connected for sectioning the power distribution line, and with regard to current electrical quantities on the power distribution line.

Abstract: To prevent obstacles to wiring caused when wiring from other nets pass through the vicinity of a terminal, and moreover, to carry out automatic wiring having shorter wiring length and increased wiring completion rate, when calculating wiring costs of a wiring route of a net, for unwired terminals belonging to other nets, wiring route cost values for the net to be wired are variably assigned depending on distance from these terminals. In other words, in the present invention, cost values are established such that the cost weighting decreases with distance from unwired terminals of other nets. Seen from a different viewpoint, in the present invention, cost values are established such that cost increases for wiring routes passing within a prescribed range of an unwired terminal of another net. Incorporation of the above-described set cost value into the calculation of wiring costs enables automatic wiring that reduces cost, shortens wiring length, and prevents occurrence of unwired nets.

Abstract: A folded dielectric film element is provided which converts energy. The film element includes at least one dielectric film that is bent into folds and provided with electrodes. The electrodes are arranged in the folds so that different electrodes are placed in successive folds. The strength of an electric field increases in one fold and decreases in a successive fold.

Abstract: A multi-function control switch for electrically operating devices, such as a lighting system, is disclosed. The multi-function control switch includes a rocker-type actuating arm for actuating a plurality of momentary switches. When actuated, the momentary switches send signals to an electronic operating module which houses a control logic circuit. The control logic circuit receives input keying sequences from the user, and interprets the input to determines whether the input keying sequence is associated with any of the command logic elements stored in its memory, and whether the system may validly switch from the current operating function to the new operating function. If the transition is valid, the control logic circuit signals the electronic operating module to execute the command logic element associated with the new operating function.

Abstract: A bidirectional current blocking switch is disclosed. The switch includes a four-terminal MOSFET in which there is no source-body short. The voltages applied to the source and drain terminals are both higher than the voltage applied to the body terminal (for an N-channel) device so that the source-body and drain-body junction of the MOSFET never become forward-biased. The switch of this invention is particularly useful for switching a cascaded set of batteries in a portable computer.

Abstract: The bus line of an electric power system is connected to an inverter which can be placed in a forward operation mode or in a reverse operation mode, and batteries are connected to the inverter to store the dc energy thereof. When a commercial power source is normal, an ac switch is closed, so that the inverter is placed in the forward operation mode to perform an active filter operation for eliminating harmonic current and reactive current. When necessary, the batteries are charged, and the inverter is placed in the reverse operation mode to perform a peak cut power generation. At loss of the commercial power source or momentary drop of the supply voltage, the switch is opened so that the inverter is placed in the reverse operation mode to perform an UPS operation (emergency power generation). Hence, electric power is supplied without interruption to an important load and the emergency load.

Abstract: An apparatus and method for switching between two power supplies, a primary power supply and a secondary power supply. The present invention generates a first reference voltage using the voltage of the primary power supply and the secondary power supply, wherein the primary power supply voltage is variable. The present invention also generates a second reference voltage based on the voltage of the primary power supply. The first and second reference voltages each have a different slope and the crossing point between these two reference voltages indicate that a switch between the primary power supply and the secondary power supply should occur.

Abstract: A trickle power supply for a light switch module according to the invention enables power to an electronic circuit to be taken directly off the hot line. The power supply operates under what is referred to as the "switched leg theory". All power is taken off the standard switched leg of the light circuit. The power supply bleeds enough current to power its electronic circuitry without turning on the load device, i.e., the light. At the same time, the maximum current to the load is limited to prevent shorting out of the power supply which would effectively disable the switch module.

Abstract: n (an integer of two or more) resistors are serially connected between a first terminal to which a first voltage is applied and a second terminal to which a second voltage is applied. Gates of the (n+1) MOS transistors are connected to the corresponding one among the first terminal, the second terminal, and nodes between n resistors. The sources of the (n+1) MOS transistors provide (n+1) different output voltages.

Abstract: The present invention is a printed circuit board having conductive layers split into electrically isolated voltage supply plane regions each plane region being connectable to an external supply voltage. The voltage supply plane regions are split to reduce the total number of PCB conductive layers. Voltage supply plane regions are configured to match the device voltage requirements and their placement on the PCB. In the case in which a circuit includes a device having two voltage supply requirements, a first set of the device's power supply pins are fixedly coupled to a first voltage supply plane region and a second set of the device's power supply pins are fixedly coupled to a second voltage supply plane region. In this instance, each of the first and second voltage supply plane regions are fixedly connectable to external voltage supplies or to a voltage regulator according to the voltage supply requirements of the device.