Abstract: A hair perming device and its temperature control circuit are disclosed. The temperature control circuit for a hair perming device is electrically connected with a heater of the hair penning device and comprises a main control module and a trigger module. The main control module controls the trigger module to be switched on such that a control signal outputted by the main control module can be sent to the heater for heating, and meanwhile for detects a working state of the trigger module. When a failure of the trigger module is detected, the main control module controls the trigger module to be switched off such that a continuous heating of the heater is stopped. When a failure of the trigger module is detected, the electrical power supply path of the heater is disconnected, and a continuous heating of the heater is stopped for avoiding excessive high temperature.

Abstract: A method and apparatus for operating a power distribution system, includes providing a solid state switch downstream of a power source and upstream of an electrical load, the solid state switch operable in a conducting mode that enabling conduction from upstream to the output and a non-conducting mode that disables conduction from the input to the output, and providing a transient voltage suppressor defining a breakdown voltage upstream of the solid state switch.

Abstract: A shorting cap apparatus is provided for enabling remote application of power, by an external system, to a load connected to the shorting cap apparatus while protecting components of the external system from potential damage due to high inrush current to the load. The shorting cap apparatus comprises a housing, a connector, and inrush current protection circuitry. The connector of the shorting cap apparatus may be connected to a corresponding connector associated with the load. Once the external system applies power, the protection circuitry provides a time delay to allow the load to sufficiently charge via a first set of resistors of the protection circuitry over a period of time before a set of switches of the protection circuitry are transitioned to a conducting state.

Abstract: The disclosed embodiments provide a system that facilitates operation of a power adapter in hiccup mode. The system includes a bleeding mechanism that reduces a hiccup time of the hiccup mode by increasing a leakage current of the power adapter. The system also includes an activation mechanism that activates the bleeding mechanism upon detecting a voltage drop associated with the hiccup mode.

Abstract: An autorecloser circuit including a relay circuit with an electromagnetic relay configured to be coupled between an AC power source and a customer location to deliver current from the AC power source to the customer location. A controller coupled to the relay circuit is configured to control the electromagnetic. A current sense circuit coupled to the controller is configured to detect an amount of the current that is delivered to the customer location and a reference voltage circuit coupled to the controller is configured to establish a reference level for the amount of the current that is delivered to the customer location. A power circuit coupled to the controller and to the relay circuit is configured to provide a DC power source to the controller and to the relay circuit from the AC power source. The controller is configured to disconnect or reconnect the AC power source from the customer location based on the detected amount of current.

Abstract: A protecting circuit connected between a power supply and a load includes an interface unit, a switching unit, a protection module, a locking unit, and a trigger unit. The interface unit is used for connecting to the load. The switching unit turns on to establish a connection between the power supply and the load when the interface connects to the load and turns off to cut off the connection. The protection module generates a protecting signal when the output of the power supply is in an abnormal state, and the locking unit controls the trigger unit to generate a control signal. The switching unit cuts off the connection in response to the control signal. When the output of the power supply resumes to a normal state, the switching unit automatically resumes the connection by reconnecting the interface with the load.

Abstract: An electronic fuse (506, 507) suitable for use in a direct current, DC, applications which is exposed to surges. The electronic fuse (506,507) comprises a current sensor (500) for measuring a current flowing in a current path of the DC system, the electronic fuse comprising a first transistor switch (501) which is arranged in the current path, the first transistor switch comprising at least one parasitic diode (511) having a forward direction which is opposite to an operational DC direction of the current path. The electronic fuse further comprising a controller (502) operatively connected to the current sensor (500) and adapted to control the first transistor switch (501) based on the measured current, and a current restrictor (503,520) which is capable of blocking a current from flowing in the current path in a direction opposite to the operational DC direction.

Abstract: A lighting controller includes a housing and a power transformer mounted in the housing for stepping down an inputted AC power signal at a first higher voltage to at least one output AC power signal at a second lower voltage for powering a plurality of light fixtures. The controller further includes a switching device that can be closed and opened to connect and disconnect a primary winding of the power transformer to a source of AC power that can provide the inputted AC power signal. At least one wire connection terminal is connected to a secondary winding of the power transformer. A face pack is removably mounted in the housing and is operatively connected to the source of AC power and the switching device. The face pack includes a display, at least one manually actuable input device, a processor, a memory operatively connected to the processor, and an operational program stored in the memory.

Abstract: Testable current limiting with hiccup reset is provided. In one embodiment, a current limiter comprises: a current regulating circuit having a pass-transistor wherein a load current delivered to a load side flows through the pass-transistor, the current regulating circuit clamps the load current when the load current exceeds a threshold; a latch regulating circuit coupled to the current regulating circuit, and further coupled to a line side through a semiconductor having a turn-on voltage threshold higher than the pass-transistor; and a current limit test circuit configured to apply a reference impedance to the load side output. The latch regulating circuit compares a voltage from the current regulating circuit to a voltage measured at the semiconductor to determine when the load current exceeds the threshold. When the load current exceeds the threshold for a period of time exceeding a predetermined duration, the latch regulating circuit temporarily shuts off the pass-transistor.

Abstract: An inrush current higher than a second anomaly threshold current ILfc passes through a power MOSFET 14, when a control signal S1 of low level is applied to a gate driver 28 so that the power MOSFET 14 and the like turn to a conductive state. A first forcing shutoff operation for the power MOSFET 14 is then prevented, because a first anomaly threshold current ILoc is set to an initial level higher than the inrush current. A fuse time counter 73 starts a count-up operation in response to the occurrence of the inrush current, and continues to increment its count value until a load current IL falls below the second anomaly threshold current ILfc. According to the count value, the first anomaly threshold current ILoc is decreased stepwise with time.

Abstract: A circuit breaker is disclosed that provides a warning that the current through the circuit breaker exceeds a warning threshold. The circuit breaker comprises: a switch that carries a current I; an indicator for alternatively indicating: (i) that the current I has not exceeded IW, and (ii) that the current I has exceeded IW; and an actuator in series with the switch that: (i) causes the indicator to indicate that the current I has exceeded IW when and only when the current I has exceeded IW, and (ii) opens the switch when and only when the current I exceeds IT; wherein 0<IW<IT.

Abstract: A device for protecting electronic equipment having an output terminal includes an electronic breaker switch linked between the output terminal and ground, and a protection means which protects the electronic breaker switch against overvoltages applied to the output terminal. The protection means includes a means for detecting a current above a given threshold flowing in the electronic breaker switch, a means for prohibiting the closing of the electronic breaker switch when the current flowing in the electronic breaker switch is above the given threshold, and a means for permitting the closing of the electronic breaker switch after a given duration following a prohibition.

Abstract: Disclosed herein is a Fourier transform-based phasor estimation method and apparatus capable of eliminating the influence of exponentially decaying DC offsets. According to a Fourier transform-based phasor estimation method according to an embodiment of the present invention, an input signal is sampled, and samples of one-cycle data of the input signal are separated into at least two sample groups. A Discrete Fourier Transform (DFT) is performed on each of the sample groups. A DC offset included in the input signal is calculated on a basis of results of the DFT on each of the sample groups, and an error caused by the DC offset is calculated using the calculated DC offset. A phasor of a fundamental frequency component included in the input signal is estimated by eliminating the calculated error, caused by the DC offset, from the results of the DFT on the input signal.

Abstract: A short circuit protection circuit which readily recovers a relay drive circuit to an output operation state after a short circuit is cancelled while preventing the relay drive circuit from being damaged by a short circuit. The relay drive circuit outputs a drive current to a load in accordance with a first control signal. A short circuit detection circuit detects the occurrence of a short circuit at an output side of the relay drive circuit and suspends output operation of the relay drive circuit when a short circuit occurs. Further, the short circuit detection circuit intermittently transmits a recovery signal to the relay drive circuit in a certain time interval after a predetermined time elapses from when the short circuit occurs to recover the output operation of the relay drive circuit. The time interval is gradually increased whenever the recovery signal is transmitted.

Abstract: To provide a semiconductor integrated circuit including: a detection circuit that detects an occurrence of latch up and can be configured while adopting a layout configuration that suppresses the occurrence of latch up; and a recovery unit that enables a recovery from the latch up without cutting off a positive potential. The semiconductor integrated circuit includes: a n-channel MOS transistor 7 that is formed on a P-type region 3 on a semiconductor substrate; and a latch up detection circuit that detects an occurrence of latch up in the n-channel MOS transistor 7. The latch up detection circuit includes: a n-MOS transistor structure 12 in which a source 10 and a back gate 8 are connected in common with a source 5 and the back gate 8 of the n-channel MOS transistor 7; and an electric current detection unit 15 that detects an electric current flowing to a drain 9 of the n-MOS transistor structure 12.

Abstract: A power supply control circuit detects a reference voltage VD corresponding to an intermediate voltage of a Hi Side FET and a Lo Side FET, when a short-circuit fault of the Lo Side FET is generated, and compares a threshold value VIN?VrefH and the reference voltage VD using a comparator COMP. The power supply control circuit determines that the short-circuit fault is generated, when the reference voltage VD is less than the threshold value VIN?VrefH and a switching control signal (HiDr) is in an ON state. Likewise, the power supply control circuit detects the reference voltage VD of the Hi Side FET and the Lo Side FET, when a short-circuit fault of the Hi Side FET is generated, and compares a threshold value VrefL and the reference voltage VD using the comparator COMP. The power supply control circuit determines that the short-circuit fault is generated, when the reference voltage VD is more than the threshold value VrefL and a switching control signal (LoDr) is in an ON state.

Abstract: An autorecloser circuit including a relay circuit with an electromagnetic relay configured to be coupled between an AC power source and a customer location to deliver current from the AC power source to the customer location. A controller coupled to the relay circuit is configured to control the electromagnetic. A current sense circuit coupled to the controller is configured to detect an amount of the current that is delivered to the customer location and a reference voltage circuit coupled to the controller is configured to establish a reference level for the amount of the current that is delivered to the customer location. A power circuit coupled to the controller and to the relay circuit is configured to provide a DC power source to the controller and to the relay circuit from the AC power source. The controller is configured to disconnect or reconnect the AC power source from the customer location based on the detected amount of current.

Abstract: Electronic circuit breakers and systems for isolating a load from a power-supply unit are provided. One electronic circuit breaker includes a current sensor, a switching element coupled to the current sensor, and a switch controller coupled to the current sensor and the switching element. The switch controller is powered by the power-supply unit and is configured to switch OFF the switching element when the current sensor detects an amount of current from the power-supply unit greater than a predetermined amount. An electronic system includes a power-supply unit, a load, and the above-referenced electronic circuit breaker coupled to the power-supply unit and the load.

Abstract: Electrical distribution systems implementing micro-electromechanical system based switching devices. Exemplary embodiments include a method in an electrical distribution system, the method including determining if there is a fault condition in a branch of the electrical distribution system, the branch having a plurality of micro electromechanical system (MEMS) switches, re-closing a MEMS switch of the plurality of MEMS switches, which is furthest upstream in the branch and determining if the fault condition is still present. Exemplary embodiments include an electrical distribution system, including an input port for receiving a source of power, a main distribution bus electrically coupled to the input port, a service disconnect MEMS switch disposed between and coupled to the input port and the main distribution bus and a plurality of electrical distribution branches electrically coupled to the main distribution bus.

Abstract: An electronic circuit breaker including a two stage detection mechanism; an instantaneous trip operating at a first threshold and a delayed trip such operating at a second lower threshold. This is advantageous in maintaining operation during very short transient load peaks, which do not warrant isolation from the supply. The breaker can be line powered, can be reset remotely by controlling the line power, and can be implemented entirely in solid state electronics. As such it requires little or no service or maintenance.

Abstract: A power supply providing current interruption based on the energy from the supply over a sliding window of time is disclosed. The output current from the supply is periodically reestablished.

Abstract: Embodiments of detection circuitry are disclosed.

Abstract: A resettable short circuit protection configuration includes a power input terminal, a power output terminal, a first electrically controlled switch, which has a control end and two conducting ends, the two conducting ends being respectively electrically connected to the power input terminal and the power output terminal, a second electrically controlled switch, which has a control end and two conducting ends, the two conducting ends being respectively electrically connected to the power input terminal and the control end of the first electrically controlled switch, a first resistor, which has two opposite ends respectively electrically connected to the control end of the first electrically controlled switch and a grounding terminal, and a second resistor, which has two opposite ends respectively electrically connected to the control end of the second electrically controlled switch and the power output terminal.

Abstract: A circuit interrupter apparatus includes circuit interrupter and a device. The circuit interrupter includes separable contacts, an operating mechanism structured to open and close the separable contacts, and a trip mechanism cooperating with the operating mechanism to trip open the separable contacts. The trip mechanism includes a zone selective interlocking input and a zone selective interlocking output. The device includes a first input electrically interconnected with the zone selective interlocking input, a second input electrically interconnected with the zone selective interlocking output, and an indicator circuit structured to indicate that the zone selective interlocking input occurred at the first input or that the zone selective interlocking output occurred at the second input.

Abstract: A switched mode controller for properly handling an under-voltage condition in a power line which includes a current mirror for receiving current from the power line; a reference current source coupled to the current mirror for supplying a reference current; and a power transistor coupled to the reference current source, the power transistor generating a pulse width modulated signal when current from the power line exceeds the reference current, the power transistor being disabled when current from the power line is less than the reference current.

Abstract: An apparatus, and a method of controlling a solid state power controller (“SSPC”) selectively allows a current through a solid state power control switch in response to the current in a plurality of SSPCS exceeding at least one threshold. A microprocessor module collects power surge data from a plurality of groups of SSPCs, and determines if the amount of power surge data within a group of SSPCs is sufficient to constitute a lightning threat. If the microprocessor module determines a lightning threat is present, the microprocessor module sends a command to certain SSPCs in the afflicted group to lockout an instantaneous trip protection for the duration of the lightning threat, allowing the power surge to pass from the SSPCs to a load or plurality of loads, leaving the SSPCs undamaged.

Abstract: A power distribution unit includes a two pole circuit breaker having a first pole electrically coupled to an x-phase circuit portion of the power distribution unit and having a second pole electrically coupled to a y-phase circuit portion of the power distribution unit. The two pole circuit breaker is so designed that both of the two poles of the circuit breaker trip simultaneously and open even when an undesired electrical condition exists on the portion of the power distribution unit electrically coupled to only one of the poles.

Abstract: A method of controlling a solid state power controller includes selectively allowing a transient current through a solid state power control switch in response to the transient current exceeding at least one threshold.

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: An automatic circuit recloser is automatically removed from service prior to battery failure. Logic implemented on the automatic circuit recloser is used to determine whether a battery of the automatic circuit recloser may power operation of the automatic circuit recloser in place of a primary power source of the automatic circuit recloser is determined. The logic is also used to signal for the automatic circuit recloser to be automatically tripped when the battery may not power operation of the automatic circuit recloser in place of the primary power source. The logic also may be used to determine whether the battery is of a marginal quality in which the capability of the battery to power operation of the automatic circuit recloser is compromised, and to issue an alarm to indicate that the battery is of the marginal quality.

Abstract: The circuit system contains an output control circuit, an output stage circuit, a current sensing circuit, and a delay circuit. The output stage circuit is driven by the output control circuit and monitored by the current sensing circuit. When the current sensing circuit determines that there is a short circuit or an abnormal current in the output stage circuit, the current sensing circuit delivers an output signal to disable the output control circuit, which in turn stops the output stage circuit. The output signal is also sent to the delay circuit which, after a period of time, provides a trigger signal to reset the current sensing circuit and to enable the output control circuit again. By providing a large enough delay time, the output stage circuit is able to sustain a very large peak current to prevent it from being damaged.

Abstract: An electronic circuit includes circuit portions for identifying a largest voltage drop through one of a plurality of series connected diode strings and for controlling a boost switching regulator according to the largest voltage drop. The electronic circuit can sense an open circuit series connected diode string, which would otherwise have the largest voltage drop, and can disconnect that open circuit series connected diode string from control of the boost switching regulator. Another electronic circuit includes a current limiting circuit coupled to or within a boost switching regulator and configured to operate with a diode load. Another electronic circuit includes a pulse width modulation circuit configured to dim a series connected string of light emitting diodes.

Abstract: A monitoring and protection circuit associated with a voltage regulator supplying power to a CMOS device can sense over current levels precisely enough for determining if a fault has occurred in a circuit of the CMOS device, e.g., latch-up, failed or shorted transistor, etc., then this monitoring and protection circuit may automatically generate a fault alert signal and/or cycle power to the CMOS device when an unexpected over current may occur, e.g., CMOS circuit latch-up. The monitoring and protection circuit may be integrated with a voltage regulator, e.g., low drop-out (LDO) voltage regulator on a single integrated circuit substrate. The monitoring and protection circuit and voltage regulator may be fabricated with a CMOS device, e.g., digital processor on a single integrated circuit substrate.

Abstract: A power saving control method includes providing a latch circuit that is supplied with current for operation from a power source even if a switch circuit is turned off, so that the switch circuit is controlled to be turned off when the latch circuit is in a latched state and turned on when the latch circuit is in an unlatched state, operating an automatic-reset operation switch so that a power off process in the main load circuit is performed and the latch circuit is turned into the latched state for turning off the switch circuit when the switch circuit is in the ON state, and operating the automatic-reset operation switch so that the latch circuit is turned into the unlatched state for turning on the switch circuit when the switch circuit is in the OFF state.

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: An electronic fuse comprising an integrated circuit having a control output terminal coupled to a control electrode of a power semiconductor switching device, the power semiconductor switching device being coupled in series with a load between first and second potentials, the integrated circuit further comprising a current sense input for sensing the current through the power semiconductor switching device, the integrated circuit further comprising a driver circuit for driving the power semi-conductor switching device, the driver circuit being coupled to a current limiting circuit responsive to the sensed current in the power semiconductor switching device, the current limiting circuit controlling the driver circuit whereby if the current through the power semiconductor switching device exceeds a predetermined threshold, the current limiting circuit generates a command to pulse the power semiconductor switching device on and off in a period of pulsed operation to maintain the current in the power semiconducto

Abstract: A limiting circuit for a brushless dc motor in accordance with the present invention comprises a first transistor, a second transistor, a first resistor and a second resistor. The first transistor, the second transistor, the first resistor and the second resistor are arranged in complementary connection to constitute the limiting circuit which has a first terminal connected to a power source and a second terminal connected to a motor drive circuit.

Abstract: The present invention provides an apparatus and method for preventing damage to a system due to runaway current and provides for the reactivation of the system. The shutdown and reactivation method and apparatus includes a driving circuit which supplies an output current to a load. If a runaway current condition occurs in the system the shutdown and reactivation apparatus is activated by triggering a shutdown signal which deactivates the driving circuit such that the output current is no longer supplied to the load. The shutdown signal activates a charging circuit, which supplies a charging current to the load. A first monitoring circuit is coupled with the load, and configured to monitor an output voltage across the load when the shutdown and reactivation apparatus is in the active state.

Abstract: The present invention is directed to a structure of a surface mounted resettable over-current protection device and a method for manufacturing the same. First, a raw material substrate having two ends is provided. On each of the two ends of the raw material substrate, a patterned conducting metal foil is formed. Then, the raw material substrate is cut to form a grid-shaped substrate having a plurality of strip-shaped structural parts. An insulating layer is formed to enclose the whole grid-shaped substrate, allowing parts of the patterned metal foil layers on the ends of the strip-shaped structural parts to be exposed. Next, the strip-shaped structural parts of the grid-shaped substrate are cut into a plurality of chips, each chip having two cut sections. Finally, two terminal electrodes are formed on the both cut sections of each chip.

Abstract: A hiccup mode current protection circuit for switched mode power converters for high power applications is provided. The circuit features a comparator for comparing an indicating voltage to a reference voltage and outputting a control signal to a disabling input where the indicating voltage exceeds a predetermined voltage threshold. The control signal also causes a switch to reduce the reference voltage to ensure that the comparator continues to output the control signal regardless of a drop in the indicating voltage. The control signal is maintained by a comparator for only a predetermined time period such that the switch eventually returns the reference voltage to its pre-reduction state, allowing the comparator to discontinue outputting the control signal if the indicating voltage is below the predetermined voltage threshold.

Abstract: An overcurrent protection arrangement comprises a switching circuit that is intended to be series connected in a line of the circuit to be protected and which will allow normal circuit currents to pass but will open when subjected to an overcurrent. The arrangement includes a pulse generator which will generate pulses when the switching circuit has opened that reset, or attempt to reset, the switching circuit to its conducting state. Only a predetermined finite number of pulses or pulses for a predetermined finite time are generated, so that the circuit will quickly function again after having been subjected to a current transient but will not continually attempt to reset in the case of equipment faults.