Abstract: A lighting apparatus includes a first substrate including a switching circuit, the switching circuit including a first port, a second port and a current control circuit configured to generate a current at the second port of the current control circuit responsive to a varying voltage at the first port. The apparatus further includes a second substrate mounted on the first substrate and including at least two LEDs electrically coupled to the second port of the current control circuit of the first substrate.

Abstract: The invention relates to a spark gap having a plurality of individual spark gaps connected in series and present in a stacked arrangement, spaced apart from each other by insulating spacers (5) and nearly free of secondary current under typical operating conditions, wherein the individual spark gaps comprise electrodes (4) and outer connection electrodes are provided, and further having control elements for influencing the voltage distribution across the stacked arrangement and/or designed as an ignition aid. According to the invention, a mechanically pretensioned insulating element (8) can be inserted or pivoted between two adjacent electrodes (4) of the individual spark gaps, in order to interrupt the main current path of the spark gap in case of fault or overload.

Abstract: A terminal and a brightness control method thereof are provided. The terminal includes an illumination sensor for measuring peripheral illumination of the terminal, a proximity sensor for detecting an object within a preset distance, a memory for storing a brightness table including data for controlling brightness of a display unit corresponding to the measured illumination, the display unit for displaying and for changing a brightness of the display unit under control of a controller, and the controller for controlling the display unit to change the brightness according to the measured illumination and the brightness table when the object is not detected. The terminal and brightness control method thereof provide a more suitable screen to a user.

Abstract: The present invention relates to an LED drive circuit, which includes a protection unit, which is connected to an AC power supply; a rectification filter unit, which is electrically connected to the protection unit; a control unit, which has an end electrically connected to the rectification filter unit; an LED driving unit, which includes an LED, a first capacitor, and a transistor, the LED being connected in parallel with the first capacitor, the LED including a positive terminal and a negative terminal, the positive terminal of the LED being electrically connected to the rectification filter unit and the control unit; and a current detection feedback unit, which is arranged between the LED driving unit and the control unit. As such, the current detection feedback unit forms a protection circuit to prevent an increase of power caused by excessively high input voltage from an AC power supply.

Abstract: Each stage of an emission control line driver includes a first transistor connected to a first node, a first power source, and a first output terminal; a second transistor connected to second node, the first output terminal, and a second power source; a third transistor connected to a second input terminal, a first input terminal, and the first node; a fourth transistor connected to the first node, the first power source, and the second node; a first controller connected to the first to third input terminals to supply sampling signal to a second output terminal; and a second controller connected to the second input terminal and a fourth input terminal to control the voltage of the second node. The first controller includes a fifth transistor connected between the first power source and the second output terminal, and to the second controller or the first output terminal via a protection unit.

Abstract: An average linear light-emitting diode (LED) driver circuit is disclosed. An inputting alternating-current (AC) voltage is connected to a rectifier bridge. An LED load is paralleled with a filtering capacitor and connected to a power switch. A compensation network and a voltage feedback network are included. When the output voltage of the rectifier bridge is higher than the voltage of the filtering capacitor, the drain voltage of the power switch is increased. The voltage feedback network decreases or turns off the current in the power switch. The compensation network controls the average current in the power switch to be equal to the desired LED load current. The average linear LED driver circuit intelligently controls the driver current, reduces the system power loss and increases the system efficiency. The LED driver maintains high conversion efficiency, especially under wide input voltage conditions.

Abstract: An LED drive circuit connectable to a phase control type light adjuster includes a first reference voltage generation portion that generates a first reference voltage, a second reference voltage generation portion that generates a second reference voltage according to a phase angle of the light adjuster, an input voltage detection portion that detects a size relationship between an input voltage and a threshold value voltage, a current draw-out portion that draws out a current in accordance with the first reference voltage or the second reference voltage from an electricity supply line that supplies electricity to an LED drive portion, and a switch portion that in accordance with a detection result by the input voltage, detection portion, performs switching between an output from the first reference voltage generation portion to the current draw-out portion and an output from the second reference voltage generation portion to the current draw-out portion.

Abstract: A light emitting diode (LED) backlight driving circuit includes LED lightbar(s) and a control module; the control module includes a dimming controllable switch. The LED lightbars are connected with the dimming controllable switch in series. Two ends of the dimming controllable switch are connected with a varistor in parallel. Because two ends of the dimming controllable switch are connected with a varistor in parallel, when the dimming controllable switch is switched off, a current of the branch circuit is suddenly reduced, the voltage withstood by the LED lightbars is greatly reduced, and the voltage on two ends of the dimming controllable switch is increased. Then, under action of high voltage, resistance of the varistors connected in parallel is reduced, and the current of a new branch circuit formed by the LED lightbars and the varistor is also increased. Thus, the voltage withstood by the LED lightbars is increased again and the voltage on two ends of the dimming controllable switch is reduced.

Abstract: A converter for feeding a load via an inductor with a current having a controlled intensity between a maximum level and a minimum level may include: a switch switchable on and off to permit or prevent, respectively, feeding of current towards said inductor; first and second current sensors sensitive to the current flowing through said switch when said switch is on or off, respectively; comparator circuitry to identify if the current intensity detected by said first current sensor and said second current sensor reaches said maximum level and said minimum level, respectively, by generating respective logical signals; and drive circuitry for said switch sensitive to said logical signals and configured to turn off said switch when the current intensity detected by said first sensor reaches said maximum level and turning on said switch when the current intensity detected by said second current sensor reaches said minimum level.

Abstract: A method for setting and adjusting light emitted from an adjustable lighting device is disclosed. The adjustable lighting device includes a timing unit and a non-volatile memory (NVM) module for storing a record data which includes a memory flag changeable between a set state and a reset state, and a plurality of light setting values. In the method, the adjustable lighting device is configured to allow a user to select an illumination state of the light, and to change the memory flag in the record data to the set state and to store the record data with a corresponding one of the light setting values when a elapsed time counted by the timing unit is longer than a predetermined threshold time period.

Abstract: Integrated circuits, control methods, and related lighting systems are provided. One integrated circuit controls the currents flowing through light-emitting-diode chains, each having several light emitting diodes forward-connected between a main cathode and a main anode while all the main anodes are connected to a power node. The integrated circuit has a short detection node, a constant current source, a voltage clamping circuit, and a short-circuit comparator. The short detection node detects the highest cathode voltage of the main cathodes. The constant current source provides a constant current to the short detection node. While the light-emitting-diode chains are unlit, the voltage clamping circuit clamps the short detection node at a predetermined voltage. When the voltage of the short detection node exceeds a threshold voltage, the short-circuit comparator asserts a fault signal, indicating a short circuit of a light emitting diode.

Abstract: A leakage current detection circuit detects a switch current flowing in a switch which is targeted for leakage monitoring, and generates a detection signal to prohibit operation of a control target circuit which is targeted for control when the switch current does not reach a predetermined threshold value.

Abstract: An illumination device includes a lamp holder, a light source, a brightness adjusting module, a light sensing unit, and a driving control unit. The lamp holder defines an inserting groove according to a connector placed above a circuit board. The automatically brightness adjusting module includes a connecting port, and is inserted into the inserting groove. The connecting port is electrically connected to the connector. The light sensing unit is position on the automatically brightness adjusting module, for receiving a light intensity and emitting a signal according to the light intensity. The driving control unit is positioned on the automatically brightness adjusting module, and electrically connected to the light sensing unit and the connecting port, for receiving the signal and emitting a driving signal, thus the light source emits lights of an corresponding illumination intensity according to the driving signal.

Abstract: A sound-controllable illumination device includes a lamp holder, a light source, a voice control module, a voice sensing unit, and a driving control unit. The lamp holder provides a small inserting groove carrying a circuit board connector and the light source is electrically controlled by the circuit board when connected. The detachable and replaceable voice control module includes a connecting port for insertion into the inserting groove. The voice sensing unit is positioned on the voice control module, for receiving preset sounds from a user and emits signals according to recognized sounds. The driving control unit is positioned on the voice control module, and carries warning lights to indicate the respective statuses of all elements.

Abstract: In an LED lamp according to one embodiment of the present invention, a PWM control unit 25 performs PWM control of a current i flowing through an LED unit 24 using by driving a pulse at a frequency higher than a predetermined frequency when a frequency of an external alternating current inputted between input terminal parts 20a, 20b is lower than the predetermined frequency, and does not perform PWM control of the current i flowing through the LED unit 24 when a frequency of the external AC inputted between the input terminal parts 20a, 20b is higher than the predetermined frequency. Accordingly, by replacing a previously mounted fluorescent lamp, the LED unit drives pulses at a high frequency and lights up for illumination, regardless of whether a ballast of an illumination device is of a glow starter, rapid starter or inverter lighting type.

Abstract: An LED lighting device includes a step-up chopper circuit for increasing an input voltage to a prescribed DC voltage, a voltage detection circuit for detecting the DC voltage, a step-down chopper circuit for decreasing the DC voltage to apply it across a light source, a step-down chopper controlling circuit for turning on and off a switching device of the step-down chopper circuit when the DC voltage is a threshold voltage or more, and an inrush current preventing circuit having a parallel circuit of a thyristor and a thermistor. When the DC voltage is less than the threshold voltage, only the induced voltage obtained from the step-up chopper circuit is employed as a drive power supply for the thyristor. When the DC voltage is the threshold voltage or more, only the induced voltage obtained from the step-down chopper circuit is employed as the drive power supply.

Abstract: The present invention provides a light source dimming control circuit, which includes a voltage signal generator for generating a first voltage signal between a predetermined voltage level and a ground level; a reference voltage signal generator for generating a reference voltage signal at an output end according to the first voltage signal and a second voltage signal; a first switch with a first end coupled to an output end of alight source; a first resistor with a first end coupled to a second end of the first switch, and a second end coupled to a ground end; a switch controller coupled to the first switch and the voltage signal generator for controlling on/off states of the first switch according to a sawtooth signal and the first voltage signal; and a current controller for controlling current flowing through the first resistor according to the reference voltage signal.

Abstract: A detection circuit according to embodiments includes a first circuit and a second circuit. The first circuit is turned OFF when an AC voltage to be input to a pair of input terminals is smaller than a prescribed value, and is turned ON when the AC voltage is equal to or higher than the prescribed value. The second circuit detects whether the AC voltage is an AC voltage leading-edge controlled by a dimmer, an AC voltage trailing-edge controlled by the dimmer, or an AC voltage having a continuous phase on the basis of at least one of the value of voltage and a gradient of the first circuit when the first circuit is turned ON while the first circuit is in the OFF state.

Abstract: A load driving apparatus related to an LED lamp and a method thereof are provided. The load driving apparatus includes a PWM-based power converter and a determination circuit. The PWM-based power converter is coupled to the LED lamp, and is configured to: generate a DC operation voltage of the LED lamp; and control a current flowing through the LED lamp in response to a dimming signal, so as to adjust a brightness of the LED lamp. The determination circuit is coupled to the PWM-based power converter and the LED lamp, and is configured to: receive the DC operation voltage; and stop conducting the DC operation voltage to the LED lamp in case that a lamp-off condition of the LED lamp is satisfied.

Abstract: A driving circuit of flat display including a charging circuit path, a discharging circuit path, and a detecting circuit is provided. The charging circuit path has first and second impedance states, wherein an impedance value of the first impedance state is smaller than that of the second impedance state. The discharging circuit path has third and fourth impedance states, wherein an impedance value of the third impedance state is smaller than that of the fourth impedance state. The detecting circuit detects whether the charging circuit path or the discharging circuit path is in an unstable first state or stable second state, controls the charging circuit path to the first impedance state or the discharging circuit path to the third impedance state in the first state, and controls the charging circuit path to the second impedance state or the discharging circuit path to the fourth impedance state in the second state.

Abstract: An apparatus and a method for driving a fluorescent lamp are provided. The apparatus submitted by the present invention includes an LC resonator and an automatic frequency tracing circuit. The LC resonator is used for receiving and converting a square signal to generate a sinusoidal driving signal for driving the fluorescent lamp. The automatic frequency tracing circuit is used for making a frequency of the sinusoidal driving signal automatically following a resonant frequency of the LC resonator according to a feedback signal related to the sinusoidal driving signal.

Abstract: Connector adapters that may allow contacts in a connector insert to form electrical connections with contacts in an incompatible connector receptacle. One example may provide a connector adapter for providing a connection between a connector insert and an incompatible connector receptacle. The connector adapter may be a magnetic connector providing a magnetic connector receptacle at a first end to accept a connector insert having an attraction plate. This connector adapter may further provide a connector insert having an attraction plate at a second end to insert into a magnetic connector receptacle on an electrical device.

Abstract: A lighting arrangement comprises a checking device and a method for the control thereof, with a sensor device containing at least one light source, where the at least one light source radiates light with high radiant power which represents a danger to the eyes of operators or service personnel. A housing, which contains the at least one light source and prevents an emergence of light of the light source, is monitored as to whether the housing is open, where the at least one light source with high radiant power is switched off if there is detected upon the monitoring an opening of the housing, which permits an emergence of light of the light source. It is provided here that a lighting arrangement is switched on at the same time or later which has a radiant power not representing any danger to the eyes of operators or service personnel.

Abstract: Embodiments of the invention provided a driving circuit for powering a light-emitting diode (LED) light source. The driving circuit includes a rectifier, a filter capacitor, and a control circuit. The rectifier converts an AC voltage from an AC power source to a rectified AC voltage. The filter capacitor coupled to the rectifier filters the rectified AC voltage to provide a DC voltage. The control circuit controls power supplied to the LED light source. The control circuit enables a discharging current periodically to discharge the filter capacitor if a switch coupled between an AC power source and a rectifier is turned off and disables the discharging current if the control circuit determines that the switch is turned on.

Abstract: A projection-type display device according to an embodiment of the invention modulates light emitted from a solid-state light source array and projects the modulated light on a screen. The projection-type display device includes a power source device that generates power used for driving the solid-state light source array using power supplied from a power source, an instant interruption detecting circuit that detects an instant interruption of the power source, and a control device that, in a case where the instant interruption of the power source is detected by the instant interruption detecting circuit, performs control of extinguishing the solid-state light source array during at least a part of an instant interruption period until recovery after the detection of the instant interruption of the power source.

Abstract: Portable electric lamp including a lighting module, and a compact case containing a power supply for supplying the lighting module and a limitation device for a current delivered by the power supply, the limitation device including a controlled limitation switch coupled between a reference terminal of the power supply and an output terminal of the lighting module, the limitation device being configured so as to determine a supply voltage between an output terminal of the limitation switch and the reference terminal, and to control the limitation switch so that it is in a closed state when the supply voltage is lower than or equal to a desired voltage.

Abstract: Disclosed is an LED driver adapted to an electronic transformer, where the LED driver can ensure that the electronic transformer meets minimum load current requirements, and operates during an entire AC period by clamping the minimum inductor current. By controlling the LED load current through a current stabilization control circuit, the LED load can operate with relatively high control accuracy and fast response speed. In addition, the LED driver can match various electronic transformers based on traditional circuit structures, and the LED load can operate without flicking.

Abstract: In one embodiment, an LED control circuit is configured to form an LED current for operating an LED light source and configured to form a bias current for a dummy load. The LED control circuit is configured to terminate the bias current responsively to detecting the LED current.

Abstract: According to certain inventive techniques, a method for operating a flickering illumination control device including an electrical input and an electrical output includes receiving an input voltage at the electrical input. A non-flickering output voltage may be provided at the electrical output. While receiving the input voltage and while providing the non-flickering output voltage, a first interruption in current flowing through the electrical output may be detected. In response to the first interruption, a flickering output voltage is provided at the electrical output.

Abstract: An intrinsically safe LED display device with an array of LED circuit cells is provided. Each cell comprises a LED or a group of LEDs, which are individually made intrinsically safe in a conventional way, by limiting a dissipated power through the LED circuit cell by means of a resistor or group of resistors in series with the LED or group of LEDs. In addition a switching type PTCs with a switching temperature between 80 and 125 degrees centigrade are added in each cell, in series with the resistors or group of resistors of the LED circuit cells respectively, in thermal contact with the resistor or group of resistors of the LED circuit cell. In this way intrinsic safety is provided for mutual heating of adjoining LED circuit cells wherein the LEDs or groups of LEDs are short circuited.

Abstract: A power supply device for plasma processing, wherein electric arcs may occur, comprises a power supply circuit for generating a voltage across output terminals, and a first switch connected between the power supply circuit and one of the output terminals. According to a first aspect the power supply device comprises a recovery energy circuit connected to the output terminals and to the power supply circuit. According to a second aspect the power supply device comprises an inductance circuit including an inductor and a second switch connected parallel to the inductor. According to a third aspect the power supply device comprises a controller for causing the power supply circuit and the first switch to be switched on and off. The controller is configured to determine a quenching time interval by means of a self-adaptive process. The quenching time interval defines the time interval during which, in an event of an arc, no voltage is generated across the output terminals.

Abstract: In examples of the embodiment, a surge-proof interface circuit (100) comprises a rectifier circuit (20) which is configured to produce a rectified rectifier output voltage at the rectifier output terminals (20c, 20d), in accordance with a rectifier input voltage at the rectifier input terminals (20a, 20b), and a Darlington circuit (30) which comprises at least two transistors (Q3, Q4). Said Darlington circuit (30) comprises a current path (35) which can be controlled on the output side in accordance with a control signal (62) and said current path (35) which can be controlled on the output side is coupled between the rectifier output connections (20c, 20d).

Abstract: An illumination device includes a transformer, a protection circuit, and a cold cathode fluorescent lamp (CCFL) tube. The transformer is for converting a first alternating current power to a second alternating current power. The protection circuit includes a relay and an over-voltage detecting circuit. The relay is coupled to a first end of the transformer, and the relay includes a contact pin, the contact pin is electrically connected to the first end when the relay is turned off, and the contact pin is electrically disconnected from the first end when the relay is turned on. The over-voltage detecting circuit is for turning on the relay when the second alternating current power is over a predetermined value, and for turning off the relay when the second alternating current power is below the predetermined value. The CCFL tube is electrically connected between the contact pin and a second end of the transformer.

Abstract: A light emitting unit driving circuit may include: an operating voltage supplying unit configured to supply a voltage input for the driving circuit; a driving unit coupled to the operating voltage supplying unit and configured to drive the light emitting unit to make the light emitting unit turn on or turn off; and a feedback control unit coupled between the driving unit and the light emitting unit, and configured to form a feedback loop together with the driving circuit and the light emitting unit to stabilize an operating current of the light emitting unit.

Abstract: A ballast circuit for a light emitting diode (LED) based lamp including power factor correction with protective isolation. The circuit includes a transformer with electrically isolated windings and a power factor correction circuit that receives no feedback from a secondary winding side of the transformer. An LED-based lamp assembly and a method of driving an LED-based light source are also provided.

Abstract: A circuit arrangement for operating a low-pressure discharge lamp may include a voltage source with two terminals; switches; and a series resonant circuit; a controller configured to control the switches such that an AC voltage is applied to the resonant circuit; a PTC thermistor coupled on one side to a circuit point of the resonant circuit and on the other side, at least one of via a diode, to the first terminal of the voltage source and, via a diode to the second terminal of the voltage source; a resistive element connected in series with a diode in the circuit between a terminal of the voltage source and the PTC thermistor; and an evaluation device configured to tap off the voltage drop across the resistive element and being coupled to the controller in order to deactivate the controller.

Abstract: An anti-flicker and anti-glow switchable load apparatus to be installed in the light socket of a commonly powered electronic switching device, such as a motion activated light switch. An energy efficient light bulb or lamp, such as a cathode fluorescent lamp or light emitting diode is then screwed into the apparatus. A first embodiment of the present invention includes a switchable light source, a switchable load, a controller, and a voltage sensor. When the present invention in the first embodiment detects a higher voltage, thus indicating the lamp has been switched from the “off” state to the on state, the switchable load is disconnected, and the current is re-routed to pass through the energy efficient lamp.

Abstract: An LED drive circuit which is connectable to a phase control type light adjuster, including: a first reference voltage generation portion that generates a first reference voltage; a second reference voltage generation portion that generates a second reference voltage according to a phase angle of the light adjuster; an input voltage detection portion that detects a size relationship between an input voltage and a threshold value voltage; a current draw-out portion that draws out a current in accordance with the first reference voltage or the second reference voltage from an electricity supply line that supplies electricity to an LED drive portion; and a switch portion that in accordance with a detection result by the input voltage detection portion, performs switching between an output from the first reference voltage generation portion to the current draw-out portion and an output from the second reference voltage generation portion to the current draw-out portion.

Abstract: A light-emitting-element lighting circuit for dimming a light emitting element having a diode characteristic by a PWM dimming signal is provided. The lighting circuit includes a dimming signal conversion unit configured to generate the PWM dimming signal having a duty ratio corresponding to an emission level specified by an input dimming signal. The lighting circuit further includes a minimum current generating circuit configured to flow a minimum current during an OFF period of the PWM dimming signal generated by the dimming signal conversion unit such that a voltage greater than a threshold voltage designed to allow the light emitting element to emit a light is applied to the light emitting element, and the light emitting element emits a light of a brightness equal to or less than a lowest emission level specified by the dimming signal.

Abstract: A lightning-proof AC LED driving device has a lightning detector breaker connected between a rectifier and an AC LED driver circuit. When lightning strikes, a high voltage enters the rectifier, and the anode and cathode of the rectifier are equipotential, making the lightning detection breaker automatically disconnect the AC LED driver circuit from the rectifier. This interrupts the connection between the rectifier and the AC LED driver circuit. Thus, the AC LED driving device has the lightning-proof function.

Abstract: The present invention is to provide an electronic ballast connected in parallel to two filaments of a fluorescent light tube, which comprises a controller for generating two output signals, two power switches being switched according to the output signals, a resonant circuit oscillating according to switching of the power switches and thereby causing a resonant capacitor thereof to generate a voltage, a voltage sensor connected in series to the resonant capacitor and connected in parallel between the two filaments so as to sense an AC voltage proportional to a voltage across the fluorescent light tube, and a regulator connected separately to the voltage sensor and controller so as to convert the AC voltage into a DC voltage and deliver the DC voltage to the controller. Upon determining that the DC voltage exceeds a preset voltage level, the controller generates an interruption control signal for immediately stopping operation of the controller.

Abstract: A LED driver comprising: a power switch; a transformer comprising a primary winding coupled to the power switch, a secondary winding and a third winding; a current sense circuit configured to sense a current flowing through the power switch and generates a current sense signal; a zero cross detecting circuit configured to detect a current flowing through the secondary winding, and generates a zero cross detecting signal; a compensation circuit configured to compensate the current sense signal based on the current flowing through the third winding; a control circuit configured to receive the compensated current sense signal and the zero cross detecting signal, and wherein the control circuit generates a control signal to control the power switch.

Abstract: According to an example embodiment of the present disclosure, a method is provided for controlling a light-emitting-diode (LED) circuit. The method includes receiving a direct current to direct current (DC-to-DC) control signal at a DC-to-DC converter. A DC voltage is generated from an input DC voltage source. The DC voltage has a voltage level that is set according to the DC-to-DC control signal. The DC voltage is provided to an LED circuit output. The DC voltage level from the DC-to-DC converter is determined. The DC-to-DC converter control signal is generated in response to the determined DC voltage level. The LED circuit is determined to have a short circuit based upon the determined DC voltage. In response to determining that the LED circuit has a short circuit, the DC-to-DC converter is disabled from providing the DC voltage to the output for powering an LED circuit.

Abstract: An apparatus for driving a fluorescent lamp is provided. The provided apparatus includes a power switching circuit, an LC resonator and an automatic frequency tracing circuit. The power switching circuit is coupled between an input voltage and a ground potential, and configured for switching and outputting the input voltage and the ground potential in response to two output signals with a phase difference of 180 degrees so as to generate a square signal. The LC resonator is configured for receiving and converting the square signal, so as to generate a sinusoidal driving signal for driving the fluorescent lamp. The automatic frequency tracing circuit is configured for generating and adjusting the two output signals according to a current feedback signal relating to the sinusoidal driving signal, so as to make the frequency of the sinusoidal driving signal automatically follow the resonant frequency of the LC resonator.

Abstract: A lighting apparatus for a fluorescent tube and a driving method thereof are provided. The lighting apparatus includes a fluorescent tube, an open-loop protection unit and a driving device. The driving device includes an inverter and a power unit. The open-loop protection unit detects and determines an open-loop situation of two nodes of the fluorescent tube to produce an open-loop protection signal. The inverter receives a power voltage to light the fluorescent tube with a dual high-voltage method according to a trigger signal. The power unit coupled to the open-loop protection unit and the inverter provides the power voltage and determines whether to turn off the inverter according to the open-loop protection signal. When the open-loop situation of the fluorescent tube is occurred or driving voltage of the fluorescent tube is greater than a rated operating voltage, the inverter is turned off immediately to avoid components from overheating or burning.

Abstract: A electronic ballast according includes a DC power source circuit for generating a DC voltage from an AC power source, a pair of switching elements, an LC series resonance circuit, an inverter circuit for converting the DC voltage into a high frequency voltage to supply to a fluorescent lamp FL, and means such as a current transformer for detecting a current flowing into the fluorescent lamp FL, wherein oscillation of the inverter circuit is stopped when a value of a current flowing into the fluorescent lamp exceeds a predetermined value.

Abstract: An illumination system has a lighting module, a microcontroller electrically connected to the lighting module and arranged to control the lighting module, and a transistor electrically connected to the lighting module and the microcontroller arranged to allow the microcontroller to monitor a voltage of one of either the transistor or lighting module. A method of controlling a lighting module including powering on the lighting module, providing a current to the lighting module, wherein the current is determined by a global intensity setting for the lighting module, monitoring a voltage provided to the lighting module, and shutting the lighting module down if the voltage reaches a pre-determined level.

Abstract: An LED driving circuit is provided for making it possible to economically drive a serially connected LED circuit by means of a switching device with a relatively low withstanding voltage even if the number of serially connected LED devices increases. In an LED driving circuit provided with a serially connected LED circuit (11) in which many LED devices are serially connected and a switching device (13) serially connected with the serially connected LED circuit (11) to control that an electrical current flowing through the serially connected LED circuit (11) is turned on or off, wherein a circuit device (15), which comprises a resistor, a constant voltage diode, a constant current diode, or the like, is connected in parallel with the switching device to make a minute current flow through the serially connected LED circuit (11) to the extent that the LED devices are not turned on when the switching device is turned off.

Abstract: There is provided a lamp capable of informing a user that the LED lamp is at the end of its productive life and urging the user to replace the lamp reliably with a simple configuration. The lamp includes: a light emitting diode (1) as a light source; and a driving circuit (3) that turns on the light emitting diode (1) by an alternating-current or direct-current power source. The lamp further includes a life detecting element (2) that turns off the light emitting diode (1) following the occurrence of insulation deterioration in a resin material when the light emitting diode (1) has been operated for a predetermined time.

Abstract: This disclosure describes systems, methods, and apparatuses for extinguishing electrical arcs in a plasma processing chamber. Once an arc is detected, the steady state voltage provided to the plasma processing chamber can be reduced, and the current being provided to the chamber decays below a steady state value as the arc is extinguished. When the current falls to or below a current threshold, the voltage can be ramped back up bringing the voltage and current back to steady state values. This technique enables power to return to a steady state level faster than traditional arc mitigation techniques.