Abstract: A system and method for conditioning an alternating current (“AC”) power transmission for supply to a load circuit. In one aspect, the invention is a system comprising: a power conditioning circuit comprising a voltage surge protector for eliminating voltage spikes in the AC power transmission, an inrush current suppressor for limiting the current of the AC power transmission, and a voltage sensing circuit for monitoring a voltage level of the AC power transmission; means for electrically coupling the power conditioning circuit to a source of AC power; outlet means for electrically coupling the power conditioning circuit to a load circuit; and wherein the voltage sensing circuit is adapted so that upon detecting that the voltage level of the AC power transmission exceeds a predetermined upper limit, the AC power transmission is prohibited from reaching the outlet means.

Abstract: A power interruption protection module, system and method. The power interruption protection module, comprising a charging module for storing a boosted display voltage, a detecting module for identifying at least one of a drop or an increase of a functioning system voltage, wherein at least one of the drop or the increase is beyond a threshold, and a regulating module for receiving a signal from the detecting module, wherein the signal determines at least one of the drop or the increase beyond the threshold, and wherein the regulating module allows or stops the flow of the stored boosted display voltage of the charging module according to the signal of the detecting module.

Abstract: A battery protection and monitoring system includes a plurality of MAFET (Mechanically Actuated Field Effect Transistor) switches, wherein each MAFET switch among the MAFET switches is capable of switching from an open switch condition to a closed switch condition or vice versa, such that the plurality of MAFET switches are connectable to a battery. Such a system further includes one or more transistors associated with and which communicate electrically with at least one MAFET switch among the MAFET switches. A PPTC (Polymeric Positive Temperature Coefficient) device is also associated with the transistors and the MAFET switches, such that the PPTC device, the MAFET switches and the transistors operate in association with one another and the open switch condition or the closed switch condition of the plurality of MAFET switches to identify, monitor and thus prevent at least one dangerous condition associated with the battery.

Abstract: Systems and methods that detect a phase loss condition in a three-phase electrical power source are presented. The system includes a detection component that measures and/or monitors a magnitude and frequency of a voltage of a power source, and a controller component that compares measured and/or monitored voltage characteristics to characteristics associated with phase loss.

Abstract: There is provided an apparatus for protection against over voltages and/or under voltages. The apparatus includes a pass transistor through which an input voltage is applied, the input voltage varying between a low voltage and a high voltage, and means for selectively varying the gate voltage of the pass transistor when the input voltage is transitioning from the low voltage to the high voltage or from the high voltage to the low voltage. The pass transistor may include an NMOS or a PMOS transistor.

Abstract: An output circuit for a circuit includes an input node coupled to the circuit, an output node, a reference potential terminal, a supply potential terminal, a semiconductor switch connected between the input node and the output node, and a control circuit. The control circuit is designed to open the semiconductor switch when the potential at the output node is higher than a first limit potential depending on a potential applied to the supply potential terminal, or when the potential is lower than a second limit potential depending on a potential applied to the reference potential terminal, and to close the semiconductor switch when the potential is between the first and the second limit potential. Such an output circuit has the advantage that the circuit is protected both against an overvoltage applied to the output node and a polarity inversion, wherein only monolithically integratable semiconductor devices are used.

Abstract: A microcomputer 60 takes in voltages output from the sustaining voltage Vsus generation circuit 52, the addressing voltage Vadd generation circuit 53, and the standby voltage generating circuit 54 via A/D input ports 1 through 6 mounted on the microcomputer board, and performs examinations to judge whether abnormal values are detected about the voltages. If there is at least one abnormal value detected, the main power supply is set OFF and after a predetermined time the main power supply is set ON again to perform a reexamination. If the number of times when abnormal values about a certain voltage are detected reaches the number of abnormal value detections N, the main power supply is left OFF. The number of abnormal value detections N for the Vsamp, the Vset, the Ve or the Vscan, is set larger than the number of abnormal value detections set for the Vsus or the Vadd.

Abstract: A system for improving Field Replacement Unit (FRU) isolation in memory sub-systems by monitoring Voltage Regulator Module (VRM) induced memory errors. A comparator compares the output voltage coming from the VRM to memory. If the comparator detects a VRM output voltage transient that is outside a rated threshold, then a counter is increased by one. If the counter exceeds a count threshold, a VRM error is posted. If a memory failure occurs within a predetermined period of time, then the VRM error pinpoints the VRM output voltage transient as being the likely cause of the memory failure.

Abstract: A system and a method are disclosed for providing a temperature compensated under-voltage-lockout circuit that has a trip point voltage that is not sensitive to temperature variation. The under-voltage-lockout circuit of the invention comprises (1) an inverter circuit that is coupled to a supply voltage and (2) a temperature compensation circuit that is coupled to the supply voltage and to the inverter circuit. The temperature compensation circuit and the inverter circuit temperature compensate a trip point voltage of the inverter circuit by driving an input of the inverter circuit with a voltage that has a same temperature coefficient as the trip point voltage of the inverter circuit.

Abstract: A load status indicator is disclosed for determining whether power is available to, and current is flowing through, a load. A first visual status indicator may light up when power is available to the load but current is not flowing through the load. A second visual status indicator may light up when power is available to the load and current is flowing through the load. A bi-color light-emitting diode may comprise the first and second visual status indicators. Transistors may be used to permit or prevent current from flowing through the visual status indicators. In some embodiments, a reed switch or a hall-effect sensor may be used to determine whether current is flowing through the load.

Abstract: For driving one or more gas discharge lamps (2) to conduct or to block at any time and at the same time, a rectangular high voltage is generated from a high DC voltage, an alternating voltage with respect to a reference voltage (V?) is generated from the rectangular voltage, the alternating voltage is supplied to first electrodes (4) of the lamps, second electrodes (6) of the lamps are selectively connected to the reference voltage, a current flowing through each lamp is stabilized (26), the alternating voltage is filtered to provide a filtered voltage, a property of the filtered voltage is measured to provide a control signal, the control signal is used to control the frequency of the rectangular voltage, and the filtering has a response characteristic which is substantially identical to a response characteristic provided by a lamp when conducting and means for said stabilizing of current flowing through the lamp.

Abstract: A peak voltage protection circuit for protecting an associated High Voltage NPN transistor (T3) against breakdown, the protection circuit comprising a Low Voltage NPN element (T15) for sensing a sensor voltage related to a base-collector voltage of the associated High Voltage NPN transistor (T3). The circuit further comprises an activation circuit for limiting the base-collector voltage of the associated High Voltage NPN transistor (T3) upon triggering. The Low Voltage NPN element (15) is coupled to the activation circuit for triggering it upon the sensor voltage exceeding a breakdown voltage of the Low Voltage NPN transistor (T15).

Abstract: In one embodiment, a fault control circuit of a switching power supply controller is configured to disable an operating voltage of the switching power supply controller responsively to a fault condition and to subsequently decouple the fault control circuit from another operating voltage.

Abstract: A power management IC including a dual purpose pin, a fault detection system, and a fault signature system. The dual purpose pin performs a power management function during normal operation (e.g., a soft start pin coupled to an external capacitor, a set pin coupled to an external resistor, a frequency set pin coupled to a resistor-capacitor combination, etc.). The fault detection system senses any of multiple fault conditions and provides a corresponding fault indicator signal, each indicating a corresponding fault condition. The fault signature system generates a selected fault signature signal on the dual purpose pin, where each fault signature signal has a characteristic indicative of a corresponding fault condition. Thus, an existing pin on the IC is re-used to indicate the fault condition. The fault signature signal may be a unique voltage level, a unique charging rate, a unique frequency signal, or any a combination thereof.

Abstract: A DC high power distribution system provides power to a load in parallel with one or more storage capacitors. The system includes a hot-swap controller and an array of parallel-connected transistors connected in series between a DC source and the capacitors/load. A power contactor is connected in parallel to the transistor array, both of which are connected to control outputs of the controller. The controller monitors various circuit conditions of interest, such as input over-voltage, input under-voltage, and over-current. If the circuit conditions meet designated parameters, the controller activates the transistors for charging the capacitors, for limiting inrush current. After charging, the controller activates the power contactor for shunting the transistors and carrying the 150+ ampere current during ongoing operation. If any of the monitored circuit conditions fail to meet designated parameters, the controller halts operation of the circuit by deactivating the power contactor and/or transistors.

Abstract: An integrated circuit is disclosed including a primary input for receiving an input voltage, a battery voltage input for receiving a battery voltage signal and an output for providing an output voltage higher than the battery voltage. First circuitry responsive to the input voltage is provided for turning off the output voltage responsive to an input over voltage condition. Second circuitry responsive to the battery voltage signal is provided for turning off the output voltage responsive to a battery over voltage condition. Third circuitry provides for over current protection.

Abstract: Device miniaturization is made possible by building a battery protection circuit in a microcomputer. A secondary battery protection device includes a voltage detection device that detects a voltage of a power supply circuit including a secondary battery, a current detection device that detects a current of the power supply circuit, and a battery protection circuit that shuts off the power supply circuit based on a signal representing a detection made by the voltage detection device or the current detection device of an excess current that is generated in the power supply circuit. The protection circuit is built in a microcomputer.

Abstract: In one embodiment, a voltage protection circuit uses two back-to-back transistors to receive an unprotected voltage and form a protected voltage.

Abstract: The switched mode power supply comprises an inductor, a switching transistor, a controller circuit coupled to the switching transistor, a rectifying means and a feedback regulation loop for providing a stabilised output voltage. It comprises further a protection circuit coupled to an output or input of a comparator of the controller circuit for providing an overvoltage protection in case of a failure of the regulation loop. The protection circuit comprises in particular an integrating circuit and a comparating circuit. In a preferred embodiment, an output of the protection circuit is coupled to a sense input of the controller circuit, for switching off the controller circuit immediately in case of a failure. In another aspect of the invention, the protection circuit comprises further a second comparator coupled to the first comparating circuit for the surveillance of the input voltage of the switched mode power supply, and for the detection of a short circuit of the inductor or the rectifying means.

Abstract: A constant voltage output circuit has an output power transistor supplied with electric power form a first input power source and a control circuit supplied with electric power from a second input power source. Here, when the voltage from the first input power source is equal to or higher than a predetermined level Va, an overcurrent protection circuit and a short-circuiting protection circuit operate. Furthermore, yet another protection circuit is provided that operates even when the voltage from the first input power source is lower than the predetermined level Va.

Abstract: A method to detect the presence of battery protection circuits in any battery powered product. The major advantage of the method is to make the battery voltage very smooth during the charging process. The proposed circuit can give a good prediction of protection switching turn on time. This can provide the battery powered system work smoothly by avoiding any battery voltage discontinuity. The proposed invention addresses the issue of deep discharge and provides a solution through a discharge test procedure.

Abstract: An integrated circuit arrangement includes connection terminals, an undervoltage detector, and at least one circuit unit. The connection terminals are configured to receive a supply voltage. The undervoltage detector is coupled between the connection terminals and is configured to compare the supply voltage with a select reference value selected from a first reference value and a second reference value. The second reference value is less than the first reference value. The undervoltage detector is further operable to produce a detector signal on the basis of a result of the comparison. The circuit unit is coupled between the connection terminals, and includes a first operating state with a first drawn current and a second operating state with a second drawn current. The second drawn current exceeds the first drawn current. The select reference value corresponds to an operating state of the at least one circuit unit.

Abstract: To reduce the electric power wasted in an overvoltage protection circuit, a regulator IC 100 incorporates an overvoltage protection circuit 105 that stops the output operation of the regulator when the output voltage Vo becomes higher than a predetermined threshold voltage Vth1. The overvoltage protection circuit 105 includes switch means FET3 that turns on and off the overvoltage protection operation thereof according to a predetermined control signal.

Abstract: The battery pack according to the present invention is to avoid any trouble or the like of the primary or secondary battery inside the battery pack with a simple mechanical construction when a load is intermittently connected between the external terminals of the battery pack. For this end, the battery pack includes at least the battery cell and a protection circuit for shutting off overcurrent discharge and features in the provision of shut-off holding means and releasing means. The shut-off holding means maintains discharge shut-off condition after abnormal discharge shut-off by shorting or connecting a low resistance between the external plus terminal and the external minus terminal from outside of the battery pack. The releasing means releases the shut-off condition of the shut-off holding means when a predetermined voltage is applied between the external plus terminal and the external minus terminal.

Abstract: The invention is a high electrical energy storage system consisting of arrays of high energy capacitors and their charging and discharging protocols. An array of capacitors are conductively connected together and connected to an energy source. A computer and software control the charging and discharging of the capacitor banks.

Abstract: A power controller for power sourcing equipment in a distributed power network provides power down policies and priority in the event of a power supply failure. The power down priority and policy permits implementation of a rapid decrease in the power demand of the distributed power network to avoid overload of a backup power supply. The priority may be derived based on the relative position of port information in a linked list. Devices associated with a high priority can remain powered in response to a main power supply failure, while lower priority devices can be rapidly powered down to reduce the overall load demand on the backup power supply. The ability to configure ports on the basis of priority and available policies provides a flexible and simple implementation of a response in the event of a main power supply failure.

Abstract: A load status indicator is disclosed wherein a green light-emitting diode of a bi-color light-emitting diode lights up when power is available to but not being used by a monitored device, whereas a red light-emitting diode of the bi-color light-emitting diode lights up when the monitored device is drawing current. The load status indicator utilizes a coil in series with the monitored device, a reed switch controlled by the coil, and field-effect transistors to control which light-emitting diode lights up depending on whether power is available and whether the monitored device is drawing current.

Abstract: A load abnormality detection circuit serves to stop the operation of a load when the load is shorted to a VB power supply, or when the load is layer shorted, whereby heat damage of a load control transistor is prevented. A microcomputer provides a drive signal to a base of the transistor thereby to drive the load. A voltage detection circuit detects a voltage level between a collector and an emitter of the transistor and inputs it to the microcomputer. The microcomputer sets first and second thresholds corresponding to the voltage levels of a collector voltage of the transistor when the load is abnormal, and detects when the load is abnormal based on a comparison of the voltage level detected with the thresholds. The presence or absence of abnormality of the load is detected based on at least two comparison results.

Abstract: A primary side control module for a switching power supply and a method for protecting a MOSFET that is controlled by a controller chip of the type that includes a timing network and switching drive output pins. The module includes the controller chip and the MOSFET. The controller chip provides a gating signal at the switching drive output pin to the MOSFET that may regulate the passage of current through the primary winding of a transformer of a switching power supply. A circuit branch provides communication between the throughput of the MOSFET and the timing network pin of the controller chip. A capacitor is provided within the circuit branch to differentiate the throughput and provide a signal characterized by downgoing spikes that result in protection of the MOSFET from burnout due to abnormalities associated with the internal operation of the controller chip.

Abstract: In one aspect, a power connect device receives ac line voltage and provides ac load voltage to a load device. In one embodiment, the power connect device includes: a connect panel, a transformer circuit, a high voltage relay, a rectifier, and a voltage protection circuit. In one aspect, the transformer circuit includes first, second, and third transformers each with a primary winding, a high voltage secondary winding, and a low voltage secondary winding. In several embodiments, methods protect the load device from an over or under voltage conditions on the ac load voltage using the power connect device. The power connect device is reconfigurable for three phase and single phase operation. The power connect device is also reconfigurable for multiple line voltage levels.

Abstract: An integrated circuit comprising a source voltage monitoring unit that monitors the level of a first source voltage supplied from an external power source, determines whether the first source voltage is supplied from the external power source, and controls an internal power source and the external power source; so as to apply the first source voltage, when determining that the first source voltage is supplied; and so as to apply a second source voltage supplied from the internal power source, whose level is lower than that of the first source voltage, when determining that the first source voltage is not supplied, wherein the integrated circuit operates with application of either one of the first source voltage and the second source voltage.

Abstract: A method and system for improving Field Replacement Unit (FRU) isolation in memory sub-systems by monitoring Voltage Regulator Module (VRM) induced memory errors. A comparator compares the output voltage coming from the VRM to memory. If the comparator detects a VRM output voltage transient that is outside a rated threshold, then a counter is increased by one. If the counter exceeds a count threshold, a VRM error is posted. If a memory failure occurs within a predetermined period of time, then the VRM error pinpoints the VRM output voltage transient as being the likely cause of the memory failure.

Abstract: A receptacle which is defined in a given interface standard, performs data transfer by using differential signals, and is connected to a plug when transmitting a signal between devices. The receptacle includes: a power supply terminal; a ground terminal; a first differential signal terminal used for transmitting a first differential signal; a second differential signal terminal used for transmitting a second differential signal, the second differential signal terminal making a pair with the first differential signal terminal; and at least one protection element provided between the power supply terminal and the ground terminal.

Abstract: An analog or digital circuit that senses both low and high input voltage and operates to disconnect both line and neutral electrical power connections to a protected device when abnormally low or high voltages are received from a single- or multi-phase power source, and reconnects the protected device when input power has stabilized. The sensing circuit and power supply is functional with voltages up to at least 240 Vac. The nominal 120 Vac circuit is designed to withstand a 6 kilovolt surge without damage. The apparatus does not disconnect the ground line during an out-of-tolerance voltage condition.

Abstract: A transfer switch configured particularly for use with traffic signal controllers, to enable a traffic signal controller to be powered by a portable electrical generator, when utility line power is unavailable. A housing, configured to be mounted either on the surface of a traffic signal controller cabinet, or recessed into an opening of the cabinet, so as to be flush to the surface thereof, is provided. The housing is configured to be substantially weatherproof without requiring the use of gaskets.

Abstract: The protection circuit serves for the monitoring of output voltages of a power supply unit which has a normal mode and a standby mode. The protection circuit comprises a first switching stage (T1), coupled to the current input (1) of which are output voltages (U5–U8) which are present both in the normal mode and in the standby mode and coupled to the control input of which are output voltages (U1–U3) which are only present in the normal mode. A control signal (Us), by which the power supply unit is switched over between normal mode and standby mode, is coupled to the control input (2) of this switching stage (T1). As a result, by means of the control signal, the output voltages which are only present in the normal mode are blocked in the standby mode by the control signal, so that in the standby mode only the output voltages (U5–U8) which are coupled to the current input (1) are monitored.

Abstract: One disclosed embodiment of the invention is directed to circuit control that comprises sensing a delivered voltage to a portion of an integrated circuit, determining an appropriate frequency for the portion of the integrated circuit, and providing the appropriate frequency to the integrated circuit.

Abstract: Apparatus for detecting failure of an isolation device includes a current sensor to sense current through the isolation device and a circuit responsive to the current sensor output signal and to an enable signal that controls the isolation device for providing an Early Failure Warning (EFW) signal indicative of whether the isolation device has failed. The enable signal is at a first logic level when the isolation device is on and is brought to a second logic level to disable and test the isolation device. Also described is a method of detecting a failure of an isolation device including disabling the isolation device, sensing a current through the isolation device, and providing an EFW signal indicating that the isolation device has failed if the current through the isolation device is greater than a predetermined level when the isolation device is disabled.

Abstract: Methods and apparatuses for fault condition protection of a switched mode power supply. In one aspect of the invention, a power supply circuit having an auto-restart function to turn the power supply on and off repeatedly under fault conditions is included. In one embodiment, one or more off-times following detection of a fault condition is smaller than subsequent off-times.

Abstract: A circuit for protection of a transceiver input includes an input transistor and a first resistor connected between the drain of the input transistor and an input node. A plurality of reverse-biased diodes connected between a supply voltage and the input node. An output node is connected to the source of the input transistor. A first forward-biased diode connected between the power supply and the plurality of reverse-biased transistors. A second forward-biased diode and a second resistor are connected between the first forward biased transistor and the gate of the input transistor. A pre-driver circuit includes first and second transistors forming a differential pair and driven by a differential input voltage. A third transistor is connected between sources of the first and second transistors and ground. First and second resistors are connected to drains of the first and second transistors, respectively. A fourth transistor is connected between a power supply voltage and the first and second resistors.

Abstract: A control circuit for a frequency converter is provided. The control circuit includes a switch circuit, a timer switch, a starter circuit, a starter relay, and a timer relay. The control circuit is capable of keeping the frequency converter on for a predetermined time period when the voltage level of the power supply is below a predetermined voltage level in order to keep the equipment operating. After the lapse of the predetermined period, if the voltage level is still below the predetermined voltage level, the circuit stops to the operation of the equipment to protect the equipment.

Abstract: A circuit arrangement for operating a sensor comprises a control circuit for electrically supplying the sensor via a plurality of connecting lines and/or at least to detect one electrical output signal of the sensor in which case one of the connecting lines is routed via one actuatable switching element that is suitable for interrupting this line, and to detect the potential on at least one of the connecting lines and should an abnormal potential be detected on this connecting line, to actuate the switching element for interrupting the connecting line. Furthermore, one actuatable further switching element is provided for connecting a pair of connecting lines and the circuit arrangement is designed in such a way that it can actuate the connection of these connecting lines, should an abnormal potential of this further switching element be detected, to break down a potential difference between connections of the sensor.

Abstract: A power source monitor and method to monitor various operating line conditions of an electrical power outlet comprising measuring line voltage and frequency, analyzing wiring conditions, displaying the line conditions and generating an alarm when any of the line conditions are not within a corresponding predetermined range.

Abstract: A present invention provides a PDA with built-in voltage protection, comprising a main device, a socket, and a voltage protection module. The main device performs necessary data processing. The socket connects to an adapter. The voltage protection module is coupled between the main device and the socket, wherein the voltage protection module receives an input voltage from the adapter and allowing the input voltage to be applied to the main device when the input voltage is between a preset maximum voltage and a preset minimum voltage.

Abstract: A network device is disclosed. The network device includes an incoming power port, an outgoing power port, an internal circuit, and a power storage system connected to the incoming power port, the outgoing power port and the internal circuit. In alternative embodiments, the device may include a power regenerator, a power detector and divider, or a power splitter.

Abstract: A voltage sensing device automatically scales the source and network phase voltages of a power distribution system having one of two operating voltages for input to a network protector relay and also automatically scales a voltage for operating the trip and close circuit of the circuit breaker in the network protector. A latching tap select relay only switches the system voltages to the lower operating voltage input taps of step down transformers after a short delay if all the system voltages are in the lower operating range. A diagnostic circuit verifies proper switch position and voltages before closing output contacts to connect the scaled voltages to the relay and circuit breaker.

Abstract: A semiconductor circuit in a semiconductor substrate includes a first input for feeding a first supply potential, a second input for feeding a second supply potential higher than the first supply potential, a device, an output and a parasitic pn-junction between the device and the semiconductor substrate, which is conductive at a first polarizing potential at the output smaller than the first supply potential or at a second polarizing potential at the output greater than the second supply potential. A protective circuit whose electric resistance at the first polarizing potential at the output and at the second polarizing potential at the output, respectively, is higher than at a normal operation potential at the output lying between the first supply potential and the second supply potential is connected between the output and the parasitic pn-junction.

Abstract: An integrated circuit (IC) has logic and timing circuits that are coupled to discrete circuitry to provide protection and indications whenever an AC adapter that is faulty or has improper voltage levels or polarity are plugged into a system. In particular, the IC device provides over-voltage, under-voltage, and reversed-polarity protections to an electronic system to keep the electronic system from being damaged by an alternating current (AC) adapter having an improper voltage range or voltage polarity. It also provides a protection that prevents an adapter from powering a host system that has a short-circuit fault.

Abstract: There is provided a semiconductor integrated circuit that hardly causes an unnecessary operation time for variable control over an operating frequency and an internal power supply voltage. A CPU specifies an operational clock signal frequency to a clock generation circuit and an internal power supply voltage to a power supply circuit. The power supply circuit comprises a voltage regulator and a determination circuit to determine a transition state to a specified internal power supply voltage. The CPU uses a first signal to notify which time point the power supply voltage variable control start to the power supply circuit. The power supply circuit returns a second signal to the CPU to notify at which time point the power supply voltage variable control terminated.

Abstract: A single input pin (48) provides multi-functional features for programming a power supply (10). By connecting the appropriate interface circuit (92, 100, or 112) to the single input pin (48), the power supply (10) is programmed for specific behaviors during power up and toggling of an on/off switch (96, 108). In one mode of operation a light emitting diode (106) in the interface circuit (100) is optically coupled to a microprocessor for signaling the closure of the on/off switch (108), allowing the microprocessor to control the power supply (10) through an opto-coupler (102). In another mode of operation, the single on/off switch (96) controls the power supply (10). In yet another mode of operation, Zener diode (118) in the interface circuit (112) controls the power supply (10) during brown-out and black-out conditions.