Abstract: The present invention relates to a battery protection circuit for protecting a plurality of batteries connected in series. The battery protection circuit includes: a controller for monitoring the batteries and outputting control signals based on predetermined conditions associated with the batteries; a first N-channel MOSFET and a second N-channel MOSFET coupled in a common-drain configuration in a low-side path, wherein at least one of the first and second N-channel MOSFETs turns off in response to the control signal received from the controller when at least one of the predetermined conditions is detected; and a gate protection circuit for preventing gate-to-source voltages of the first and second N-channel MOSFETs from exceeding a predetermined gate-to-source voltage level.

Abstract: A regulator for a switched mode power supply includes switching regulator logic, a counter and a logic gate. The switching regulator logic is coupled to receive a feedback signal and to generate a switching signal in response. The feedback signal periodically cycles between a first state and a second state when the power supply operates normally. The counter is coupled to receive the feedback signal and an output of the counter indicates an auto-restart mode of the regulator in response to the feedback signal remaining in the first state for a predetermined count. An output of the logic gate enables the power switch to turn on and off in response to the switching signal when the output of the counter does not indicate the auto-restart mode and the output of the logic gate disables the power switch in response to the output of the counter indicating the auto-restart mode.

Abstract: The present invention relates to a device arranged for converting an AC input voltage to a DC output voltage, comprising a bridgeless boost converter; and a surge protection system. The surge protection system comprises a first protection diode (Dprot1), where the anode is connected to a first AC input terminal and the cathode is connected to a positive boost output terminal (Obp); a second protection diode (Dprot2), where the anode is connected to a negative boost output terminal (Obn) and the cathode is connected to the first AC input terminal; a third protection diode (Dprot3), where the anode is connected to a second AC input terminal and the cathode is connected to the positive boost output terminal (Obp); and a fourth protection diode (Dprot4), where the anode is connected to the negative boost output terminal (Obn) and the cathode is connected to the second AC input terminal.

Abstract: An over-voltage protection device includes a comparison module, a first switch, a second switch and an output switch. The comparison module compares a divided input voltage with a threshold voltage to output a control signal according to the comparison result. The first switch is coupled with the comparison module and controlled by the control signal. The second switch is coupled with the first switch and is controlled by the output signal of the first switch. The output switch is coupled with the second switch, the output switch is coupled with the voltage output terminal, and the output switch is coupled with the voltage input terminal. The output switch is controlled by the output signal of the second switch to cut off the input voltage or pass the input voltage to the voltage output terminal.

Abstract: Circuitry is disclosed that comprises: a high voltage rail for providing a high voltage level corresponding to a first higher voltage domain; an intermediate voltage source, a low voltage rail; and a plurality of devices configured to operate in a second lower voltage domain; said circuitry being configured such that a first set of said plurality of devices are arranged in an upper voltage region where they are powered between said high voltage rail and an intermediate voltage rail powered by said intermediate voltage source and a second set of said plurality of devices are arranged in a lower voltage region where they are powered between said intermediate voltage rail and said low voltage rail, said circuitry being configured such that on power up said intermediate voltage source is powered before said high voltage rail, said circuitry further comprising: an isolating circuit arranged in said upper voltage region, said isolating circuit comprising at least one switching device for connecting said intermediat

Abstract: In a charging circuit charging a battery based on a power supply voltage from an external power supply, a charging transistor is provided on a path from the external power supply to the battery. A charging control circuit is integrated on a semiconductor substrate, and adjusts an ON state of the charging transistor to control a charging current supplied to the battery. The voltage adjusting circuit provided on an electric power supply path from the external power supply to a power supply terminal of the charging control circuit generates a necessary voltage drop. The current adjusting circuit adjusts the ON state of the charging transistor such that a voltage of the battery is brought close to a predetermined voltage value. The clamp circuit clamps a voltage at the power supply terminal of the charging control circuit below a predetermined clamp voltage.

Abstract: A voltage converter includes an electronic induction device, a switch device, a protection circuit, and a control circuit. The switch device, electrically connected to the electronic induction device, is utilized for selectively establishing an electrical connection between the electronic induction device and a predetermined voltage level according to a control signal. The protection circuit, coupled to the electronic induction device, is utilized for selectively establishing an electrical connection between the electronic induction device and the predetermined voltage level, wherein the protection circuit is enabled to establish the electrical connection when a current passing through the switch device exceeds a predetermined current limit. The control circuit, coupled to the switch device, is utilized for generating the control signal.

Abstract: It is desired for semiconductor devices to reduce an inrush current and an overshoot. According to the voltage regulator circuit of the present invention, when a power supply is turned on, a switch SW1 is turned on in response to a control signal CTR1, a switch SW2 is turned off, and a reference voltage Vref is input to the first (+IN) and second (?IN) inputs of a differential amplifier AMP1 as a common voltage. When a common voltage is supplied to the first (+IN) and second (?IN) inputs, the current I flows into a smoothing capacitor C1 from the high-voltage power supply (VDD) via the differential amplifier AMP1 is regulated to be small. Namely, an inrush current can be reduced. Further, according to the voltage regulator circuit 30 of the present invention, the increase of the output voltage Vout from the differential amplifier AMP1 is relaxed so that the overshoot can be suppressed.

Abstract: A windscreen wiper, including a protection device for an electric motor for drive thereof, and corresponding method. The windscreen wiper includes a DC motor with first, second, and third carbon contacts rubbing on a rotor thereof. The first carbon contact is ground, the second is selectively connected to a DC current supply, and the third is connected to neither the ground nor the DC current supply. A sub-assembly for detection of sticking of the electric motor provides information on the sticking of the motor. A voltage measuring device between the first and the third carbon contacts permits taking a first measured voltage value that is compared to a first threshold value to generate further second information on the sticking of the electric motor if the voltage is lower than the first threshold value.

Abstract: Disclosed is a method and apparatus for detecting an overcurrent condition in a dimmer circuit having two switches, each for controlling power delivered to a load, each switch having a respective anti-parallel diode. The method comprises sensing a voltage drop across one of the anti-parallel diodes, comparing the sensed voltage drop with a reference voltage, and determining that an overcurrent condition exists if the sensed voltage drop exceeds the reference voltage. Also disclosed is a dimmer circuit embodying the method.

Abstract: A driving circuit for driving at least one lamp includes a power switching circuit, a first transformer and a feedback control circuit. The power switching circuit is electrically connected with a power source to generate an input current. The first transformer includes a primary winding and a secondary winding. The primary winding is electrically connected with the power switching circuit. The secondary winding is for transforming the input current to drive the lamp. The feedback control circuit is connected in parallel with the primary winding in order to measure a voltage variation of the primary side and output a power control signal. The power switching circuit adjusts a current for driving the lamp according to the power control signal.

Abstract: The present invention includes: a main voltage detection unit for detecting a voltage applied between main electrodes of an electrical power switching element; a control current source for injecting a current into a gate electrode of the electrical power switching element in accordance with the voltage detected by the main voltage detection unit; a main current detection unit for detecting a main current flowing between the main electrodes of the electrical power switching element; and an adjustment unit for adjusting a current of the control power source in accordance with the main current detected by the main current detection unit.

Abstract: An excess-current protection circuit includes an outer input terminal, an outer output terminal, a driver transistor connected between the input terminal and the output terminal to control an excess current, an excess-current control circuit, and an excess-current detection circuit. The excess-current control circuit compares a predetermined first bias voltage with a voltage obtained by a current flowing through a first sense transistor multiplied by a resistance value of a sense resistor and controls the gate voltage of the driver transistor in accordance with a comparison result. The excess-current detection circuit compares voltage difference between the drain and source of the driver transistor with a predetermined second bias voltage and controls the gate voltage of the driver transistor in accordance with a comparison result.

Abstract: A power protection apparatus including: a switch unit connected in series in a power supply line from a power source to a DC regulator; a first short-circuit detector for detecting a short circuit based on an output voltage value of the DC regulator obtained by making the switch unit conductive for predetermined time and, after that, interrupting the switch unit; a second short-circuit detector for detecting a short circuit based on a value of current flowed in the switch unit when the switch unit is conductive; and a switch interrupting unit, when a short circuit is detected by the second short-circuit detector, for forcedly interrupting the switch unit regardless of a state of the switch unit controlled by the first short-circuit detector.

Abstract: A circuit for voltage transient protection is provided. The circuit includes an input monitor circuit, an input transistor, and a voltage regulator. The input transistor is connected between the input voltage and the input voltage terminal of the voltage regulator. The input monitor circuit asserts an input monitor circuit output signal if the input voltage reaches a pre-determined level. When the input monitor circuit output signal is asserted, and gate and source of the input transistor are shorted together (to disconnect the input of the voltage regulator from the input voltage), and the voltage regulator is disabled.

Abstract: A DC-DC converter includes a chip including an error amplifier and a pulse width modulator (PWM) having an input connected to an output of the error amplifier, and an inductor driven by said PWM in series with an output node (VOUT) of the converter, wherein a load current flows through the inductor. VOUT is fed back through a network including a feedback resistor (RFB) to an inverting input of the error amplifier. A circuit for sensing the load current includes a first operational amplifier, a sense resistor on the chip having resistance RSENSE coupled to an inverting input of the first amplifier; wherein a sense current related to the load current flows through the sense resistor, a dependent current source provides an output current to supply the sense current. A reference resistor is disposed on the chip having a resistance RREFERENCE which is a fixed multiple of RSENSE. A set resistor is provided having a resistance RSET.

Abstract: Aspects of the invention are directed to methods and apparatus to protect an inverter from failure due to neutral lifting. In one aspect, the present invention provides a method of controlling an inverter in a UPS, the inverter being selectively coupled to a power line and comprising an input to receive an input voltage from the power line. The method comprises acts of monitoring the input voltage, detecting based on the act of monitoring, that the input voltage exceeds a predetermined high threshold value, isolating the inverter from the power line responsive to detecting that the input voltage exceeds a predetermined high threshold value, determining whether or not a neutral lifting condition exists on the power line, indicating that the inverter is in a fault state if the neutral lifting condition exists, and reconnecting the inverter to the power line if the neutral lifting condition does not exist.

Abstract: The present invention relates to a protection circuit, a resonance converter having the same, and a protection method thereof. A resonance converter having high-side and low-side switches senses a current flowing through the low-side switch and determines a zero voltage switching failure by using a width of a current flowing to a negative direction of the low-side switch.

Abstract: Fault-sensing and protecting apparatus for soft start circuit of inverter and method for the same are proposed. The soft start circuit of inverter includes a soft-starting resistor and a relay. The relay has a normally-open end connected to the soft-starting resistor in parallel. The fault-sensing and protecting apparatus for soft start circuit includes a central processing unit (CPU) and a photo coupler. The CPU is electrically connected to the inverter and an input end of the relay, respectively. The photo coupler includes a light emitting diode (LED) and a photo transistor. The LED is first electrically connected to a resistor in series and then electrically connected to the soft-starting resistor in parallel. The photo transistor is electrically connected to CPU. After the inverter starts to work, the CPU cuts out voltage applied to the inverter if the LED is lit. Therefore, the inverter can be prevented from damage.

Abstract: A measuring arrangement of the invention includes: At least one measuring device, which generates, repeatedly during operation, measured values, especially digital, measured values, representing the at least one measured variable to be registered; as well as an electronic data processing system superordinated to the at least one measuring device, especially a data processing system which is spatially distributed and/or spatially remote from the measuring device. Measuring device and data processing system are connected together by means of at least two line-pairs, through each of which an electrical current flows, at least at times, during operation. According to the invention, the measuring device transmits the internally generated, measured values to the data processing system via both line-pairs. In this way, it is then possible to transmit a plurality of measured values simultaneously, when each of the two line-pairs is embodied as part of a two-conductor current-loop.

Abstract: A protection circuit for a parallel power system having at least two parallel coupled voltage regulators is disclosed. The protection circuit includes at least two isolation control circuits, each control circuit being coupled to a respective voltage regulator. Each isolation control circuit includes a current sense circuit for sensing current polarity at an output of the respective voltage regulator, and a controller for automatically isolating the respective voltage regulator when an over-voltage condition exists at an output of the parallel power system and a positive current polarity is sensed at the output of the respective voltage regulator. The at least two isolation control circuits isolate only a voltage regulator having positive current outflow during the over-voltage condition. In one embodiment, each isolation control circuit further includes an over-voltage detection circuit for detecting when the over-voltage condition exists at the output of the parallel power system.

Abstract: A fault protection system for an AC-DC distribution system detects the presence of DC content at individual loads, isolates the load responsible for the fault from the remainder of the distribution system, and blocks DC content from being propagated from the faulty load to the AC source. The fault protection system includes at least one circuit breaker connected to monitor the AC current provided to the individual electrical load and to detect the presence of DC content indicative of the load being faulty. In response to detected DC content, the circuit breaker trips open to disconnect the electrical load from the AC distribution system to prevent DC content from being propagated to adjacent loads.

Abstract: A power converter includes a transformer, a switch element, a control circuit, an over-current detecting circuit, and a compensation signal generating circuit. The transformer includes a primary winding and at least an auxiliary winding. The control circuit is coupled to the switch element, and controls on/off status of the switch element to control a primary current flowing through the primary winding. The over-current detecting circuit compares the primary current with a current limit, and then controls the control circuit to turn off the switch element if the primary current is greater than the current limit. The compensation signal generating circuit is coupled between the auxiliary winding and over-current detecting circuit, and provides an adjustment value to calibrate the current limit according to an output of the auxiliary winding; wherein the adjustment value varies with time when the switch element is turned on.

Abstract: Overcurrent and overload protection for the power output of a pulse-width-modulated digital audio system is disclosed. The overcurrent protection circuitry includes a latch that is set in responsive to output current from the power output stage that exceeds an overcurrent threshold; the output of the latch gates the pulse-width-modulated control signal to block power output for the remainder of the current pulse-width-modulated cycle; upon the end of the cycle, or the beginning of the next, the latch is cleared to enable power output in that next cycle. Overload protection is provided by circuitry including counters for counting the relative number of overcurrent cycles to normal, non-overcurrent cycles, and generating an overload signal to block power output in the event of too frequent overcurrent cycles.

Abstract: An overcurrent protection system and method are disclosed. In one embodiment the overcurrent protection system includes a first switch connected between a supply voltage and an output voltage. A comparator circuit provides a comparator output signal having first and second values that depend on a comparison of the output voltage relative to the supply voltage, the first value indicating an overcurrent condition. A control circuit is coupled to provide a control signal to a control node of the first switch for controlling the first switch in one of first and second operating modes according to the value of the comparator output signal. The control circuit controls the first switch in the first mode to limit the current through the first switch to a level between predetermined upper and lower current levels in response to the comparator output signal having the first value.

Abstract: A power converter controller circuit is disclosed. In one aspect, a power converter controller circuit includes a control circuit to generate a switching signal to be coupled to a power switch to control power delivered to an output of a power converter. A timing circuit is to be coupled to the power switch and coupled to receive a feedback signal and the switching signal. The timing circuit is to disable the power switch from receiving the switching signal in response to the feedback signal after detection of a fault condition. The feedback signal repeatedly transitions between first and second states in response to the output when the power supply operates normally. The feedback signal maintains its state when the power supply is in the fault condition. The feedback signal transitions between the first and second states independently from the switching signal.

Abstract: A method and apparatus for determining a corrected monitoring voltage, at least a portion of the method being performed by a computing system comprising at least one processor. The method comprises generating power at a first location; monitoring the generated power by measuring a first voltage proximate the first location; measuring a second voltage proximate a second location, the first and the second locations electrically coupled; and determining, based on the measured second voltage, a corrected monitoring voltage to compensate the measured first voltage for a distance between the first and the second locations.

Abstract: A discontinuous conduction mode (DCM) converter is provided. The converter comprises a transformer having a primary and a secondary side, an RCD network, a rectifier, a switch, and a controller. The transformer has primary side with a first primary winding and a second primary winding and has a secondary side with a secondary winding. The RCD network is coupled to the first primary winding and is adapted to receive energy from the leakage inductance of the first primary winding. The rectifier is coupled to the second primary winding. The switch is coupled between the RCD network and ground. The controller receives indicia of a rectified voltage from the rectifier, indicia of current from the switch, indicia of transformer magnetization and controls the actuation of the switch. Preferably, the controller provides an actuation signal to the switch with actuation periods that are separated from one another by an interval that allows energy within the transformer to substantially dissipate.

Abstract: Provided is a voltage regulator for limiting a rush current from an output stage transistor. The voltage regulator includes an output current limiting circuit having a low detection current value and an output current limiting circuit having a high detection current value, and is structured so as to enable operation of the output current limiting circuit having a low detection current value during a time period from a state in which an overheat protection circuit detects overheat and an output current is stopped to a state in which an overheat protection is canceled and a predetermined time passes. Accordingly, after the overheat protection is cancelled, an excessive rush current can be limited.

Abstract: A consumer electronic product that includes a media player arranged to process a selected one of a plurality of digital media files stored therein and a media delivery accessory unit detachedly connected to the media player arranged to broadcast the processed digital media file. When the consumer electronic product is in a DC mode, the consumer electronic product controls a transfer of an amount of charge between the media delivery accessory and the media player. In one embodiment, the amount of charge is sufficient to for the consumer electronic product to operate for a predetermined amount of time. In another embodiment, the amount of charge is sufficient for to maximize an amount of time that the media player and media delivery accessory can operate.

Abstract: A method of performing loadflow calculations for controlling voltages and power flow in a power network by reading on-line data of given/specified/scheduled/set network variables/parameters and using control means, so that no component of the power network is overloaded as well as there is no over/under voltage at any nodes in the network following a small or large disturbances.

Abstract: The present invention is an overvoltage protection and automatic re-strike circuit for an electronic ballast. The electronic ballast has an inverter, a shut-down circuit, a safety circuit, a monitoring circuit, and an overvoltage protection circuit. The inverter provides an appropriate alternating current power supply to operate the lamp. The shut-down, safety, monitoring, and overvoltage protection circuits are coupled to the inverter and provide the overvoltage protection and automatic re-striking functions. During an overvoltage condition, the overvoltage protection circuit will temporarily disable the inverter. Subsequent to the overvoltage condition, the overvoltage protection circuit permits the inverter to attempt to re-ignite the lamp. After a predetermined number of unsuccessful re-ignition attempts, the safety circuit will permanently disable the inverter to avoid damage to the ballast.

Abstract: An apparatus to provide overvoltage protection is shown. The apparatus comprises a boost converter (having an output node, a sensing network, and an impedance network) and a zener diode. The zener diode is coupled to the output node and to the sensing network. The breakdown value of the zener diode is selected to be greater than a desired voltage drop across a load when the load is coupled to the output node, and the zener diode creates an overcurrent fault in the boost converter when the voltage at the output node is greater than its breakdown value.

Abstract: Protection circuitry protects a boost converter coupled between input and output nodes for driving a load coupled to the output node. The protection circuitry may comprise a first circuit configured for monitoring a voltage at the output node, the voltage being caused by a signal having a voltage proximate to, or lower than, an input voltage of the boost converter. The protection circuitry may also include a second circuit configured for coupling together the input node with respect to the output node and enabling the boost converter only if the monitored voltage exceeds a reference voltage.

Abstract: A device for monitoring and protecting electrical equipment, placed in series on a power supply line between an electrical power source and the equipment, includes: at least one voltage regulator for regulating a power supply voltage of the equipment, at least one current limiter, coupled to the voltage regulator to reduce the power supply voltage of the equipment if a power supply current absorbed by the equipment exceeds an upper operating value, at least one crowbar short-circuit device, adapted to be activated when the input voltage exceeds a safety limit value, higher than the upper operating value, and to cause a fuse placed in series between the power source and the equipment, to blow, and calculating and storage elements adapted to generate a clock and to log a date of occurrence of a fault and the operating parameters of the power supply for the equipment in a non-volatile memory.

Abstract: The present invention provides a power supply control system comprising a first switch circuit configured to set a power supply line which connects a power supply unit and a power supply circuit to one of a connected state and a non-connected state, a first control unit configured to operate in one of a normal mode and a sleep mode in which a consumption current is smaller than in the normal mode, and to detect a magnitude of a current flowing into the first switch circuit and control an operation of the first switch circuit based on the detected magnitude of the current while operating in the normal mode, and a second control unit configured to control an operation of the first control unit based on the detection result of an opening-closing state detection unit configured to detect an opening-closing state of a battery lid provided to the power supply unit.

Abstract: The invention relates to a circuit arrangement for the selective operation of at least two electric machines (1, 2) that are each supplied via a plurality of phase lines, comprising:—one voltage protection module (5) for limiting an intermediate circuit voltage,—one switch arrangement (4) for selecting one of the electric machines by switching the phase lines;—first choke inductivities (8) in each of the plurality of phase lines between the circuit arrangement (4) and the voltage protection module (5), wherein one second choke inductivity (9?) each may be switched parallel to one or more first choke inductivities (8) as a function of the selected electric machine (1, 2), can be switched.

Abstract: A head lamp device for a vehicle includes a DC power source, a diode array having a plurality of series-connected light emitting diodes and a current control circuit that supplies driving current to the diode array. The current control circuit is constituted of a current supply circuit, a voltage measuring circuit, a comparing circuit that compares the voltage drop with a reference value, a judging circuit for judging that there is a short-circuiting at any of the light emitting diodes based on the comparison by the comparing circuit, and a display unit for displaying an alarm when the judging circuit judges that there is a short-circuiting.

Abstract: An exemplary voltage regulator module (VRM) control circuit includes a VRM providing a plurality of phases, each of the phases connected to a control terminal of a corresponding electric switch; a comparator comprising a non-inverting terminal connected to a first power source and grounded via the electric switches respectively, an inverting terminal connected to a reference voltage, and an output terminal; and a control switch connected between an enable terminal of the VRM and ground, the control switch comprising a control terminal connected to the output terminal of the comparator, wherein, if one of the phases of the VRM is lost, the corresponding electric switch is turned off, and a voltage of the non-inverting terminal of the comparator is higher than the reference voltage, the comparator outputs a control signal to the control switch for turning on the control switch, thus turning off the VRM.

Abstract: In one embodiment, a protection circuit includes a linear regulator remains enabled during a portion of a time while limiting an output voltage of the linear regulator to a first value.

Abstract: An apparatus includes first and second input terminals, a conversion circuit, a current limiting resistive device, a triac and a second winding. The first and second input terminals are configured to be connected to a source of input power. The conversion circuit is operably connected to the first and second terminals, and includes a first inductive winding coupled between the first terminal and a switching device. The conversion circuit also includes a rectifier coupled between the first inductive winding and a first output, and a capacitor coupled between the first output and circuit ground.

Abstract: A switching power supply circuit that obtains a predetermined DC voltage output from an input AC power supply includes a full-wave rectifier and a boost circuit connected to the rectifier. The boost circuit generates a DC output having a predetermined voltage value from the rectifier output. A power factor improving circuit controls an ON-period of an output transistor of the boost circuit, based on feedback of the DC voltage output, and a dynamic over-voltage-protection circuit controls the ON-period of the output transistor as it performs a switching operation. The switching power supply circuit facilitates an over-voltage-protection function that prevents inductor buzzing with an integrated circuit having a small number of pins.

Abstract: A regulator with a high side pass device and a low side pass device coupled in series to the high side pass device is disclosed. The apparatus further includes a control module coupled to the high side pass device and the low side pass device. The control module is coupled to the high side pass device and the low side pass device to control the high side pass device and the low side pass device. The control module is operable to lock out the high side pass device under certain conditions.

Abstract: There is described circuit arrangement which comprises a protection element. A state of the protection element is determined in a simple and safe manner by means of a detection unit and a specification unit, in addition to an evaluation unit.

Abstract: System and method for common mode translation in continuous-time sigma-delta analog-to-digital converters. An embodiment includes a loop filter having an RC network coupled to a differential signal input, a Gm-C/Quantizer/DAC circuit (GQD) coupled to the loop filter, a common-mode level adjust circuit coupled to signal inputs of the GQD, and a tuning circuit coupled to the GQD and the common-mode level adjust circuit. The GQD evaluates an input signal provided by the RC network. computes a difference between a filtered input signal and the feedback quantization signal to generate an error signal, measures the error signal, and compensates for the error signal with sigma-delta noise-shaping. The common-mode level adjust circuit alters a common-mode level of a differential input signal to be substantially equal to a desired common-mode level and the tuning circuit provides a compensation voltage to the common-mode level adjust circuit based on a difference between the common-mode levels.

Abstract: By using switching power supplies a, b, and n, which have detection function of over-current, over-voltage and low voltage, in the case where a short-circuit occurred in a load which is connected to output of a switching power supply, and in the case where a MOSFET of the switching power supply is in a short-circuit state and broken, a main power is forced to be off, and a failure log of the switching power supply is stored in a non-volatile memory unit EEPROM; and also in the case where the main power was turned off and on, even if an abnormal log of the switching power supply logged in the non-volatile memory unit, reclosing of the main power is suppressed and which of the switching power supply occurred failure is notified to the outside.

Abstract: A boost converter includes a load disconnect switch connected between a voltage input terminal and an inductor, a power switch connected to the inductor by a switching node, a diode connected between the switching node and a voltage output terminal, and an output capacitor connected to the voltage output terminal to provide an output voltage. A protection apparatus is connected to the load disconnect switch, switching node and power switch to monitor the voltage at the switching node and the output voltage to provide open circuit and short circuit protection for the boost converter.

Abstract: An apparatus in an electronic control system allows two or three wire operation. A power supply can supply power to the enclosed circuitry in both two and three wire installations. Two separate zero cross detectors are used such that timing information can be collected in both two and three wire installations. Both zero cross detectors are monitored and are used to automatically configure the electronic control. Over voltage circuitry senses an over voltage condition across a MOSFET which is in the off state and turns the MOSFET on so that it desirably will not reach the avalanche region. Over current circuitry senses when the current through the MOSFETs has exceeded a predetermined current threshold and then turns the MOSFETs off so they do not exceed the MOSFETs' safe operating area (SOA) curve. Latching circuitry is employed to keep the protection circuitry in effect even after a fault condition has cleared.

Abstract: A device (22) manages power source variations in an elevator system. The device includes a transformer (60) having a primary (62) and a secondary (64). An input of the elevator system is connected to the secondary (64). Tap switches (66a, 66b, 66c, 66d) are connected to the transformer (60) such that each tap switch is connected to a tap point (68a, 68b, 68c, 68d) on the transformer (60). A controller (54) operates the tap switches (66a, 66b, 66c, 66d) based on a sensed power source output to provide power on the secondary (64) within a tolerance band of the elevator system.

Abstract: A small-scale semiconductor device having several trimming portions is disclosed. The device includes an auxiliary voltage regulator circuit outputting an output voltage and having a first trimming unit for adjusting the output voltage output from the auxiliary voltage regulator circuit; an auxiliary circuit comparing a first voltage with a second voltage and performing a prescribed operation based on the compared result, where the first voltage is in proportion to the output voltage of the auxiliary voltage regulator circuit and the second voltage is generated by a detecting unit, the auxiliary circuit including a second trimming unit for adjusting the first voltage; and a single test terminal, connected to receive any one of the first voltage and the second voltage, provided as an external terminal of the semiconductor device so as to adjust both the first and the second trimming units.