Abstract: A power supply control system for use with a tissue stimulating prosthesis, such as a cochlear implant. The power supply control system comprises a first battery (31), a second battery (32), at least a third battery (33), and a switching system (36). The first and second batteries (31, 32) are electrically connected in series to provide power to the prosthesis, while the third battery (33) is electrically connectable through the switching means (36) in parallel with either the first battery (32). The third battery (33) is electrically connected by the control system in parallel with whichever one of said first battery (31) or said second battery (32) has lowest voltage.

Abstract: A method is disclosed to add functionality to a terminal of a high voltage integrated circuit without the penalty of additional high voltage circuitry. The benefit is that alternative modes of operation can be selected for testing, trimming parameters of the integrated circuit, or any other purpose without the cost of an additional terminal. In one embodiment, ordinary low voltage circuitry monitors the voltage on the terminal that normally is exposed to high voltage. The configuration of a simple voltage detector and an ordinary latch allows easy entry into the test and trimming mode when the integrated circuit is not in the intended application, but prohibits entry into the test and trimming mode when the integrated circuit operates in the intended application.

Abstract: A MOSFET based, high voltage, high current AC electronic relay operating with normally closed contacts is disclosed. The relay includes at least one MOSFET switching circuit selectively switching between switch conducting and switch isolation. The at least one MOSFET switching circuit is normally closed and includes a plurality of inputs controlling the operation thereof. The plurality of inputs are connected to at least one rectifier such that a voltage differential exists between any two inputs of the MOSFET switching circuit providing a voltage source maintaining the MOSFET switching circuit normally closed. The relay also includes a control circuit linked to and controlling operation of the first transformer and second transformer. A switch for use in controlling operation of a MOSFET based, high voltage, high current AC electronic relay is also disclosed. The switch includes a key and a receptacle for selectively receiving the key at various positions.

Abstract: A method and apparatus for balancing a three point DC voltage intermediate circuit involves a converter circuit which influences an electrical power flow in a three point DC voltage intermediate circuit. An intermediate circuit voltage mean value is formed from a first intermediate circuit voltage across a first capacitor, and from a second intermediate circuit voltage across a second capacitor. Based on an intermediate circuit voltage mean value exceeding a threshold value, the first capacitor is connected by means of the converter circuit to an energy store, and the energy store is then connected by means of the converter circuit to the second capacitor. If the threshold value is significantly undershot, the second capacitor is connected to the energy store by means of the converter circuit, and the energy store is then connected to the first capacitor by means of the converter circuit.

Abstract: There is provided a power-on reset circuit for generating a power-on reset signal regardless of a power-up slope using not an RC delay method but a current detection method. The power-on reset circuit includes: a power supply voltage sensing node; a power supply voltage detecting unit connected to the power supply voltage sensing node, for detecting a power supply voltage level caused by a difference between a pull-up current and a pull-down current, wherein the power supply voltage detecting unit pulls down the power supply voltage sensing node if the power supply voltage reaches a threshold voltage; and a driving unit connected to the power supply voltage sensing node, for pulling up the sensing node if the power supply voltage is lower than the threshold voltage and buffering a signal of the power supply voltage sensing node to output a power-on reset signal.

Abstract: An IC device has a MOSFET serving as a power switch, a condenser connected between a first input terminal of the IC and the gate of the MOSFET, and a ferroelectric condenser connected between a second input terminal of the IC and the gate of the MOSFET. A prescribed voltage having a predetermined polarity is applied across the first and the second input terminals to generate a remanent polarization oriented in a specific direction in the ferroelectric condenser, thereby raising the threshold voltage of the MOSFET to a higher level than its original level. The power switching MOSFET is fabricated in the same manufacturing process as for other circuit blocks of the IC device such that it has substantially the same threshold voltage as that of the MOSFETs in other circuit blocks.

Abstract: A one-way switch comprises a metal-oxide semiconductor field-effect transistor (MOSFET) and a driver. Source and drain of the transistor function as P-terminal and N-terminal of the one-way switch. The driver, such as comparator or amplifier, is used to detect the voltage difference between the source and drain of the MOSFET. When the voltage of the P-terminal is higher than that of the N-terminal, the driver 150 outputs a driving voltage to gate of the MOSFET to turn on the MOSFET. If the voltage of P-terminal is lower than that of the N-terminal, the driver 150 cannot output voltage to turn on the MOSFET, and the one-way switch is off. Therefore, the one-way switch has the characteristic of workings in one direction.

Abstract: Circuit apparatus for interconnection between an electric power source of expected variability and an recreation vehicle requiring a known fixed range of voltage change. A voltage sensor (18) for producing signals representative of corresponding source voltage variation ranges. A transformer (60) with tapped primary (56,58) is selectively switched to provide low boost or high boost to compensate two low ranges of the source voltage connected by a relay (54) energized by the voltage sensor signals (18). If the source voltage exceeds the low boost range, a further relay (28) energized by a sensor signal connects the source voltage to output terminals (40,42) for ultimate use.

Abstract: A novel a circuit for driving a fan includes an output terminal for supplying the fan with drive power, a pulse width modulation driver, and a limiter. A first power terminal of the fan is held at a first voltage (e.g., 0V), and a second power terminal of the fan is coupled to the output terminal of the driver circuit. The PWM driver provides a series of fan drive pulses on the output terminal, and the limiter prevents the voltage on the output terminal from falling below a predetermined voltage. The predetermined voltage is greater than the first voltage at which the fan's first power terminal is held, and is sufficient to keep the fan in motion even when the duty cycle of the PWM signal is 0%. In a particular embodiment the limiter includes a voltage clamp. In a more particular embodiment, the voltage clamp is a diode. In another particular embodiment, the limiter includes a switch for combining a PWM signal with a DC voltage at an output.

Abstract: A sequencing system for sequencing a first node voltage at a first node and a second node voltage at a second node which is less than the first node voltage is disclosed. The sequencing system includes a bias circuit configured to provide a bias current in response to the first node voltage beginning to change to a first supply voltage. The sequencing system includes a switch configured to provide a low impedance path between the first node and the second node when the bias circuit is providing the bias current. The switch is configured to provide a high impedance path when the second node voltage is within a range of a second supply voltage which is less than the first supply voltage.

Abstract: Circuit layout to control at least one electrical component of a motor vehicle via a control signal, wherein the circuit layout comprises a digital control unit that provides an output signal during its operation, the circuit layout has a supply terminal, and the digital control unit starts its operation when the supply terminal has an operating voltage above a predetermined threshold value. The digital control unit stops its operation when the supply terminal has an operating value below the threshold value, wherein the circuit layout comprises a circuit block in order to provide for the control signal, during the operation of the digital control unit the circuit block provides for the control signal based on the output signal of the digital control unit, and the circuit block maintains the momentary control signal for a predetermined period of time after the operation of the digital control unit is ended.

Abstract: An automatic transfer switch (ATS) controller is disclosed which includes a power supply circuit to regulate and filter input power, a transformer to convert utility and generator power sources into power supply voltages and voltage sensing sources and a voltage sense signal conditioning circuit. Controller further implements a solenoid driver circuit to drive automatic transfer switch solenoids, an embedded microcontroller configured to monitor utility and generator voltages and a user interface interfaced to said microcontroller for operator entry of instructions. A LED indicator is included and is configured to verify user interface entries and overall operation of the controller and ATS system.

Abstract: Previously in a bus system, voltage signals were transmitted from the central unit to the modules, which could reply thereto by variation of the current input. A disadvantage thereby is the relatively high susceptibility to interference of the current input, which itself already must be kept relatively small due to the energy consumption, as well as the correspondingly high effort and expense for an error-free recognition of the signals transmitted from the modules in the central unit. It is now suggested, that the modules also answer to the central unit by means of voltage signals superposed on the direct supply voltage, whereby for the time duration of the signal transmission by the modules, the central unit provides the direct supply voltage to the bus line over a resistor, so that the voltage signal of the module can be detected in the central unit on the bus line on the side of the resistor facing away from the direct supply voltage.

Abstract: There is disclosed an apparatus and method for providing multiple power supply voltages to an integrated circuit. In an integrated circuit of the type comprising at least two power supply domains in which each power supply domain comprises at least one module powered by the same voltage level, the apparatus and method of the present invention blocks an output signal in a first power supply domain from being sent to a second power supply domain when the second power supply domain is in a low power mode. The apparatus and method of the present invention also blocks an output signal from a first power supply domain from being received in a second power supply domain when the first power supply domain is in a low power mode. Power sense cells are used to determine the status of power supply domains and logic circuits are used to block undesired signals. The present invention also properly synchronizes clock signals when power supply domains are activated or inactivated.

Abstract: A method and a device for bridging temporary power outages in a matrix converter are disclosed. In the event of a detected power failure, the matrix converter is disconnected from the power line and changes into a buffer mode in which a determined actual capacitor voltage space vector is regulated to a predetermined space vector. When the power line is reestablished, the actual capacitor space vector is synchronized and the matrix converter is reconnected to the power line during the synchronization. This allows a conventional matrix converter to take advantage of kinetic load buffering.

Abstract: A control structure and method for controlling a sensor heater including a power supply connected to a switching device for pulse width modulating a voltage from the power supply. The switching device is further connected to a resistance heater. A microcontroller having a single output is connected to the switching device and a single input from the microcontroller is connected to a high side of the resistance heater. The microcontroller determines a pulse width modulation duty cycle to maintain a constant power dissipation of the resistance heater.

Abstract: A circuit board includes a power switch operable so as to generate a trigger signal upon actuation, a card slot adapted for connecting with a video card, and a controller coupled electrically to the power switch and the card slot. The controller detects connection of the video card to the card slot and further detects operating voltage of the video card. The controller inhibits the power switch from generating the trigger signal upon detection that the operating voltage of the video card that is connected to the card slot is higher than a predetermined voltage.

Abstract: The method of a protection circuit includes a reference voltage source and at least one circuit which are connected together via a switch. A memory element is connected to the input of the circuit, downstream of the switch. The switch is temporarily opened by a control signal generated by a monostable circuit when detecting switching of power elements belonging to an electronic device embedding the protection circuit. When the switch is open, the memory element supplies the circuit with the reference voltage previously stored. In this way, switching of the power element that might cause noise on the reference voltage cannot disturb the circuit and thereby cannot cause a faulty operation of the latter.

Abstract: An IC device has a MOSFET serving as a power switch, a condenser connected between a first input terminal of the IC and the gate of the MOSFET, and a ferroelectric condenser connected between a second input terminal of the IC and the gate of the MOSFET. A prescribed voltage having a predetermined polarity is applied across the first and the second input terminals to generate a remanent polarization oriented in a specific direction in the ferroelectric condenser, thereby raising the threshold voltage of the MOSFET to a higher level than its original level. The power switching MOSFET is fabricated in the same manufacturing process as for other circuit blocks of the IC device such that it has substantially the same threshold voltage as that of the MOSFETs in other circuit blocks.

Abstract: A glass workpiece being processed in a vacuum plasma processing chamber is dechucked from a monopolar electrostatic chuck by gradually reducing the chucking voltage during processing while maintaining the voltage high enough to clamp the workpiece. A reverse polarity voltage applied to the chuck at the end of processing assists in dechucking. The workpiece temperature is maintained at a high value at the end of processing to assisting in dechucking. Peak current flowing through the chuck during lifting of the workpiece from the chuck controls the amplitude and/or duration of the reverse polarity voltage during the next dechucking operation.

Abstract: A control device of a cooling device controls a fan based on a desired temperature around a CPU set by a target value setting unit and a temperature detected by a temperature detecting unit, so that the temperature around the CPU substantially coincides with the set desired temperature. When the detected temperature exceeds the desired temperature, the control device causes the fan to rotate. At this time, the control device monitors the level of a noise generated by the fan by means of the noise detecting unit. The control device increases the value of the voltage supplied to the fan within a range in which the detected noise does not vary abruptly. As a result, the rotation speed is gradually increased to a predetermined value without causing an abrupt rise of a noise, which may acutely irritate the user.

Abstract: A highly reliable power supply comprises two independent input power train units each connected to a separate primary winding of a common transformer, and an output power train unit connected to the secondary winding of the transformer. A control unit controls how much energy each of the input power train units supplies. Each of the input power train units is connected to a different source of battery power or a different power distribution bus. Advantageously the advantages of full duplication of a power supply are obtained while duplicating only the input power train units. The input power train units are effectively isolated from each other through being connected to separate windings of the transformer.

Abstract: An electromagnetic switching device includes a contact arrangement with three contacts which couple a three-phase load to three phases of a three-phase power supply system, and disconnect the three-phase load from the three phases. Switching erosion takes place on the contacts. An overall erosion is determined for each contact, and is supplied to a drive circuit. The contact arrangement is operated by the drive circuit as a function of the overall erosion such that the overall erosion of the contacts are approximated to one another.

Abstract: A source-voltage-operated circuit having: an electric power source; an operated circuit section operated according to a voltage supplied by the electric power source; a control-voltage-supplying circuit section for deriving a voltage higher than the voltage supplied by the electric power source from the operated circuit section to rectify the derived voltage and output the resultant voltage as an operating voltage; and a control circuit section operated according to the operating voltage for controlling the operation of the operated circuit section and stopping the operation of the operated circuit section when the operating voltage is decreased to a given reset voltage or below.

Abstract: A voltage sag and over-voltage compensation device for an AC electric power distribution system employing cascaded switching devices and a pulse-width modulated transformer. Each stage of the cascaded switching device includes a switching element located within a full-bridge rectifier circuit to allow bi-directional switching through each switching element (i.e., switching through the same switching element during the positive and negative portions of the AC voltage cycle). Each full-bridge rectifier also includes a snubber circuit connected in parallel with a corresponding switching element to absorb the current discharge caused by switching the input power supply to the transformer through the corresponding switching device under non-zero current conditions.

Abstract: The present invention relates to an intelligent power distribution system capable of operating at a selectable output voltage, the system including a cable (1) with power bus conductors (1a, 1b) and an intelligent node (2) incorporating a controlled current switch (7) via which a power bus conductor is coupled to an output terminal (4) of the node (2) for supplying current to a load under control of the intelligent node (2). The effective value of the intelligent node output voltage is adapted settable by control of timing, or duty cycle, of the ON/OFF pulses of the controlled current switch (7).

Abstract: In a device for the short-circuiting of a first electrical line (1) with a second electrical line (2) by at least one mechanical switching device (SM), at least one first electronic switching device (SE1) is arranged in parallel with the mechanical switching device (SM) and at least one second electronic switching device (SE2) is arranged reverse-connected in parallel with said first electronic switching device, by means of which a voltage difference that occurs between the first electrical line (1) and the second electrical line (2) can be bridged. Such a device is constructed in a simple manner and has short response times.

Abstract: There is provided a power-on reset circuit for generating a power-on reset signal regardless of a power-up slope using not an RC delay method but a current detection method. The power-on reset circuit includes: a power supply voltage sensing node; a power supply voltage detecting unit connected to the power supply voltage sensing node, for detecting a power supply voltage level caused by a difference between a pull-up current and a pull-down current, wherein the power supply voltage detecting unit pulls down the power supply voltage sensing node if the power supply voltage reaches a threshold voltage; and a driving unit connected to the power supply voltage sensing node, for pulling up the sensing node if the power supply voltage is lower than the threshold voltage and buffering a signal of the power supply voltage sensing node to output a power-on reset signal.

Abstract: An improved series-pass over-voltage protection circuit for a motor vehicle electrical system includes first and second parallel connected power paths that respectively provide low current capability with low quiescent current drain, and high current capability with low on-resistance. The first power path, embodied by a P-channel MOSFET, supplies pass-through battery current to quiescent loads such as an engine control module during periods of vehicle inactivity. The second power path, embodied by at least one N-channel MOSFET, is activated by a gate voltage power supply during periods of vehicle activity. The second power path is configured to limit the circuit output voltage to a higher value than the first power path, so that the over-voltage protection during periods of vehicle activity is accomplished by the second power path.

Abstract: An electronic device does not carry out control operation corresponding to a signal from an operation button which is kept in pressed state when electric power is supplied. When electric power is supplied, the voltage changing depending on open and closed state of switches SW1 to SW4 corresponding to operation buttons to be manipulated is judged to be a specified value or not. When the voltage is not judged to be specified value, the control unit does not carry out control operation corresponding to the signal from the operation button that has been in pressed state.

Abstract: The invention relates to an electrical circuit for transmitting the state of a parameter or of an item of equipment, said electrical circuit being designed to be connected to the terminals of a power supply storage battery and comprising: an isolated link between said electrical circuit and an output (S) for transmitting an item of state information; and a switch whose open position or whose closed position is representative of the state information and which determines whether current flows through said electrical circuit, the electrical circuit transmitting the state information from the switch to the output via the isolated link.

Abstract: The method for mains-synchronous switching of circuit breakers comprises the following method steps:

Abstract: For compensation of voltage drop in a multi-conductor cable (3) connecting an electric multi-phase power source (1) with a consumer installation (4), in particular for supply of ground power to aircraft standing in airport parking positions, adjustment of the output voltage of the electric power source (1) to a level above the nominal voltage is accomplished by determining a set of cable impedance parameters and vector representations of the fundamental components of the individual output currents of the phases of the multi-phase AC power. By matrix multiplication of the vector representations of the fundamental current components by the cable model matrix a set of vector representations of fundamental voltage drop signals is calculated for the phases of the multi-phase AC power, and used as reference signals for a voltage controller (13) in the power source (1) to produce for each phase a compensation voltage for addition to the nominal voltage.

Abstract: In a DC-DC converter circuit having a plurality of input terminals connected to a plurality of DC power supplies, and an output terminal, the DC-DC converter circuit includes a power supply selection section for selecting a DC power supply of lowest voltage on the condition that the voltage is not less than a predetermined voltage, and a step-down type of regulator section for converting the voltage of the DC power supply selected by the power supply selection section into a predetermined voltage lower than the voltage of the DC power supply selected by the power supply selection section, and outputting the converted voltage through the output terminal.

Abstract: The invention relates to a switch member having one inlet and at least two outlets for transferring a signal applied to the inlet to a single one of the outlets, the switch member comprising: for each outlet, an outlet branch having at least one electronic switch whose conduction state is controlled either to transfer the signal from the inlet to the selected outlet, or else to reflect the signal; and a shunt branch having at least one electronic switch which shunts the inlet signal to a load in the event of a loss of power to the electronic switches of the member. The electronic switch of the shunt branch is connected in series and the electronic switch of each outlet branch is connected in parallel.

Abstract: The invention relates to a power supply device of a dual voltage electric system of a motor vehicle. According to the invention, a dual voltage electric system of a motor vehicle is provided, that supplies a first and a second voltage level which differ from the reference voltage, wherein power is supplied from at least one electric energy accumulator (12, 24). At least one transformer for transforming both voltage levels (18, 28) is also provided. Supply means (34, 31, 32, 36, 20) are further provided for additional supply of the energy accumulator (12, 24).

Abstract: A 2-terminal solid state electrical switch is provided which can be connected in series with a load device in a the same manner as a conventional mechanical-contact switch, does not leak current during an “OFF” state, and operates from a dynamic pulse run mode during an “ON” state. The two-terminal solid state electrical switch of the present invention requires neither a power supply to operate, nor any mechanical movement and contact points. Consequently, no spark, arc or any mechanical noise is created in the solid state electrical switch's operation, nor does it corrode, thus allowing it to be used in a hostile environment.

Abstract: A system and method for AC line voltage analysis is disclosed. According to one embodiment of the present invention, a system for AC line voltage analysis on an AC line includes a transformer that steps down the AC line voltage, a rectifier that rectifies the stepped down AC line current, a filter that filters the rectified AC line current, a voltage divider that reduces the AC line voltage; and an A/D converter that converts the reduced AC line voltage to digital bits. According to another embodiment of the present invention, a method for AC line voltage analysis of an AC line includes the steps of (1) calibrating equipment for measuring AC line voltage analysis, (2) adjusting for at least one load, (3) filtering an adjusted measurement; and (4) determining an actual line voltage.

Abstract: A control arrangement and method is provided for detecting and responding to disturbances in electrical power systems. In a preferred arrangement, an integration is initiated that is based on a comparison of actual voltage of a source and a reference voltage. When the integration exceeds a predetermined value, the source is considered unreliable. Also in a preferred arrangement, a determination is made as to whether or not the disturbance is a downstream fault condition. For example, this is useful for applications where a transfer is made from a first source to a second source when predetermined disturbances are detected. In this manner, the transfer of the load to a second source is avoided which would continue the supply of the downstream fault. Additionally, the arrangement distinguishes between various degrees of disturbances to permit appropriate response based on the severity and type of disturbance. For example, a first immediate response, i.e.

Abstract: The circuit includes a first power supply coupled to power supply sensor, which is in turn coupled to a first switch and to a third switch. A second power supply is coupled to a second power supply sensor, which is in turn coupled to a second switch and a fourth switch. A first disk drive sensor couples the first and second switches to a first disk drive. A second disk drive sensor couples the third and fourth switches to a second disk drive. The first power supply sensor examines the first power supply to recognize when a failure occurs. When the first power supply is functioning, the first power supply sensor drives the first switch to remain closed and drives the third switch to remain open. Accordingly, the first power supply powers the first disk drive. Upon recognition of a failure, the first power supply sensor drives the first switch to open and the second switch to close. The second power supply then powers the first disk drive and the second disk drive clusters.

Abstract: A voltage sag and over-voltage compensation device for an AC electric power distribution system employing cascaded switching devices and a pulse-width modulated transformer. Each stage of the cascaded switching device includes a switching element located within a full-bridge rectifier circuit to allow bi-directional switching through each switching element (i.e., switching through the same switching element during the positive and negative portions of the AC voltage cycle). Each full-bridge rectifier also includes a snubber circuit connected in parallel with a corresponding switching element to absorb the current discharge caused by switching the input power supply to the transformer through the corresponding switching device under non-zero current conditions.

Abstract: A circuit configuration for supplying voltage to an integrated circuit via a pad that is connected to the input of a Schmitt trigger on the integrated circuit. The pad is also provided for configuring the integrated circuit. The integrated circuit has a multiplicity of voltage supply lines for voltage supply purposes. According to the invention, the pad is connected to a respective voltage supply line via a respective switch, and the switches are switched on or off by a control circuit that is controlled by at least one on-chip control signal.

Abstract: A microprocessor assembly is located on a daughterboard, which is configured to be physically and electrically coupled to a motherboard. One of the electrical terminals in an electrical connector between the daughterboard/motherboard is coupled to either a ground or a voltage supply Vdd on the daughterboard, depending on the type of microprocessor used. The electrical connector passes either the ground or Vdd signal to a semiconductor device on the motherboard to automatically identify the type of microprocessor on the daughterboard.

Abstract: A voltage sag and over-voltage compensation device for an AC electric power distribution system employing cascaded switching devices and a pulse width modulated autotransformer. The autotransformer typically includes lower, center, and upper poles or taps with cascaded switching devices for selectively connecting the voltage source (i.e., a phase of the distribution line) between the lower pole and the center or upper poles. Each stage of the cascaded switching device includes a switching element located within a full-bridge rectifier circuit to allow bi-directional switching through each switching element (i.e., switching through the same switching element during the positive and negative portions of the AC voltage cycle).

Abstract: A circuit arrangement for overload protection, particularly for an evaluation electronics unit for child-seat detection in a vehicle, has first and second input connections for an input voltage signal, and first and second output connections for an output voltage signal. The first input connection and the first output connection are connected to one another by means of a first circuit path; and the source/drain path of a first field-effect transistor is included in a second circuit path from the second input connection to the second output connection, to block the second circuit path if an overvoltage is present. The source/drain path of a second field-effect transistor, is included in a third circuit path between the first circuit path and that connection of the first field-effect transistor which is coupled to the second input connection. The second field effect transistor completes the third circuit path when overvoltage is present between the first and the second input connection.

Abstract: A multi-voltage level power supply unit has a constant voltage source for providing a first voltage, a switching circuit connected to the constant voltage source and a DC/DC converter for reducing the first voltage so as to provide the second voltage. The first voltage may be 42-volts and the second voltage may be 14-volts, for example. The switching circuit is connected to the constant voltage source. And the switching circuit has a first relay designed to operate at the second voltage lower than the first voltage, a first semiconductor device and a control unit (CPU). Namely, the first semiconductor device has a first control electrode (base electrode), a first main electrode (emitter electrode) for receiving the first voltage, a second main electrode (collector electrode) connected to the first relay. And the CPU is connected to the first control electrode.

Abstract: When a relay (21) is controlled, an AC voltage (1) may be rectified in a full-wave rectification fashion. In a voltage-doubler rectification fashion, and a rectified output supplied to a main converter (6) or the AC voltage (1) may be rectified in a half-wave rectification fashion, and a rectified output supplied to a standby converter (10). A just detection circuit (23) detects a rectified voltage of the standby side, and a detection circuit (24) may detect a rectified voltage supplied to the main converter (6). The first and second voltage detection circuits (23) and (24) control operations of relay drive circuits (21D and 22D) based on both detection signals so that any one of two relay contacts (21a and 22a) may be turned on.

Abstract: A device for fault detection in a multivoltage on-board system is described which has at least one detection device, which detects a supply potential (U0) which is supplied to a power distributor (16) for supplying electrical loads (22). The power distributor supplies power to at least one electrical load (22) via at least one output (9). An additional detection device is provided, which detects the output potential (U1) at the output (9). Fault detection means (24) generate a fault signal (26) if the output potential (U1) deviates from the supply potential (U0) by a certain value.

Abstract: A supply reference voltage circuit is coupled to an output node, a supply voltage node and a supply reference voltage node and is operable to connect the output node to the supply reference voltage node and prevent current flow through an output device coupled to the output node in response to sensing a low voltage level at the supply voltage node and a non-zero voltage at the output node. The circuit is further operable to connect the supply reference voltage node to the supply voltage node in response to the voltage at the output node being a threshold voltage above the voltage at the supply voltage node. The circuit is further operable to bypass a blocking diode in response to sensing a high voltage level at the supply voltage node.

Abstract: Method and apparatus for providing alternate current paths to a junction through different sets of gate controlled SCRs coupled to the junction. The method starts with the step of initiating a switch from an active set of SCRs to an inactive set by removing a gate signal from two parallel connected, opposite sense current carrying SCRs which in combination carry AC current in either direction. Removal of the gating signal is often initiated, for example, in response to an indication that one alternating current source is faulty so that a switch to a second source is initiated. Current is then sensed through the two SCRs of the active set to determine a current carrying state for each of those two SCRs. After the state of the current carrying SCRs is determined the current carrying state of the SCRs is confirmed during a delay time period.