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WITH AUTOMATIC SHUNT AND/OR CUTOUT

Subclass of:

315 - Electric lamp and discharge devices: systems

Patent class list (only not empty are listed)

Deeper subclasses:

Class / Patent application numberDescriptionNumber of patent applications / Date published
315121000 Plural load device systems 152
315127000 Supply circuit current and/or potential actuated switch 56
315125000 Shunt circuit closing 16
315120000 Combined with signal, indicator, or alarm 13
315123000 Plural shunts and/or cut-outs 2
20130069537PIXEL CIRCUIT AND DRIVING METHOD THEREOF - The disclosure relates to a pixel circuit which includes an LED, a storage capacitor, a driving transistor, and first to third switching transistors. The driving transistor is utilized to control connection/disconnection between a power supply voltage and the LED. The first switching transistor receives a first scanning signal for controlling connection/disconnection between a gate of the driving transistor and the power supply voltage. The second switching transistor receives a second scanning signal for controlling connection/disconnection between the storage capacity and a ground voltage. The third switching transistor receives the first scanning signal for controlling connection/disconnection between the storage capacity and a data voltage. The first scanning signal and the second scanning signal are in antiphase to each other. A driving method thereof is also disclosed.03-21-2013
20120280623DIMMING APPARATUS TRANSMITTING CONTROL SIGNALS WITH AC POWER LINE - A dimming apparatus transmitting control signals with AC power line (11-08-2012
Entries
DocumentTitleDate
20110175532SYSTEM AND METHOD FOR SUPPLYING CONSTANT POWER TO LUMINUOUS LOADS - An apparatus is disclosed that is capable of delivering substantially constant power to a luminous load in response to variation in the input voltage and variation in the environment temperature. The apparatus may be further adapted to vary the power supplied to the luminous load in response to changes in the input voltage produced by a dimmer circuit. In other words, during non-dimming applications, the apparatus is able to maintain substantially constant power supplied to the load even though the input voltage and environment temperatures are varying during typical daily operations. Additionally, if the input voltage is changed due to a user controlling a dimmer device to control the brightness of the luminous load, the apparatus is able to control the power delivered to the load in response to the dimmer device.07-21-2011
20100019678CONNECTOR, A LAMP CONNECTOR, A LAMP CONNECTION CHECKING CIRCUIT, AND AN ILLUMINATION DEVICE - A lamp connector allows for checking of a connection between an external electrode of an external electrode tubular lamp and a terminal fitting into which the external electrode is fitted. Because the lamp connector into which an external electrode provided on the outer surface of an end portion of a tubular lamp is fitted includes a terminal fitting which includes a terminal piece and a terminal piece insulated from each other which are to be individually brought into contact with the external electrode, it is possible to easily check conduction between the external electrode and the terminal fitting using a tester. Accordingly, any poor fitting of the lamp into the connector can be readily found and corrected.01-28-2010
20090184647SAFETY STARTER DEVICE - A safety starter circuit for a gas discharge lamp is described, comprising a series arrangement of: a glow switch starter (07-23-2009
20100109534ELECTRONIC BALLAST WITH CONTROLLED FILAMENT PREHEATING USING HALF-WAVE LAMP CURRENT DETECTION - An electronic ballast is provided for controlled preheating of filaments in a discharge lamp. A power converter has a plurality of switching elements and converts DC power from a DC power source into AC power for the lamp. A starting circuit generates a high voltage for starting the lamp. A half-wave discharge detecting circuit detects an absolute value for each polarity peak of a lamp current, calculates an asymmetrical current value from the detected peaks with respect to a predetermined current threshold, and detects a half-wave discharge of the lamp wherein an absolute value of the asymmetrical current value is equal to or more than the current threshold for a predetermined determination time. A control circuit regulates on-times for the switching elements in an filament heating operation wherein the power converting circuit provides a high output frequency for heating each filament of the discharge lamp, and further regulates the on-times to reduce half-wave discharge detected during the filament heating operation.05-06-2010
20100109533ELECTRONIC BALLAST WITH ADJUSTABLE FILAMENT PREHEATING BASED ON OUTPUT CURRENT SYMMETRY - An electronic ballast is provided for adjustable filament preheating of a discharge lamp based on output current symmetry. A power converter receives DC power and outputs AC power. A starting circuit generates a high voltage for starting the lamp. A control circuit controls the AC power output from the power converting circuit. A symmetry determining circuit determines a positive-negative symmetrical state of the AC power output to the lamp with respect to ground. After lamp startup, the control circuit enters a filament heating operation in which the output frequency of the power converting circuit is controlled to a first frequency. At one or more predetermined current detection points during the filament heating operation, the control circuit checks the symmetry state. If the output current is symmetrical at the current detection point, the control circuit ends the frequency heating operation and enters steady state operation with an output frequency of the power converter controlled to a second frequency for maintaining lamp lighting. If the output current is asymmetrical at the current detection point, the control circuit increases the output current to the lamp and continues the frequency heating operation.05-06-2010
20100013393DISCHARGE LAMP LIGHTING DEVICE, AND ILLUMINATING DEVICE - In order to enhance stability of a discharge lamp at the time of dimming lighting even in the case where a light output is lowered, a direct current superimposing circuit superimposes a direct current voltage on an alternating current voltage applied to a fluorescent lamp, and a dimming signal correction circuit receives a detection value of a direct current voltage detection circuit and a dimming signal that is from an outside, outputs a dimming signal higher in level than the dimming signal in the case where the detection value of the direct current voltage detection circuit exceeds a first threshold value, and decreases the level of the outputted dimming signal to the level of the inputted dimming signal in the case where the detection value of the direct current voltage detection circuit falls down below a second threshold value that is equal to or less than the first threshold value. Then, an amount of alternating current power supplied to the fluorescent lamp by an inverter circuit is increased and decreased in response to fluctuations of the level of the dimming signal outputted by the dimming signal correction circuit, whereby the fluorescent lamp is dimmed.01-21-2010
20110006688LED LAMP DEVICE - This invention relates to an LED lamp device which can be applicable to a socket of a general fluorescent lamp, a halogen lamp, an incandescent lamp or the like by embodying an LED illuminating lamp powered by an alternating current (AC) through a simplified rectifier circuit and control of the number of LEDs without a dedicated circuit such as SMPS or the like when constructing the illuminating lamp using the LEDs, and which can reduce manufacturing costs and miniaturize the size of a product.01-13-2011
20090091262Discharge lamp lighting apparatus - There is provided a discharge clamp lighting apparatus including: a transformer, a transformer driving circuit, a control circuit, in which a primary side of the transformer is driven by the transformer driving circuit lighting a discharge lamp connected at a secondary side of the transformer, a discharge sensing circuit, a signal detecting circuit detecting a voltage signal induced in the discharge sensing circuit, and a protection means stopping supply of electric power to the secondary side of the transformer according to the voltage signal detected at the signal detecting circuit, wherein the signal detecting circuit includes a signal discriminating circuit attenuating a component of a voltage signal inputted from the discharge sensing circuit, the component having a frequency equal to or lower than a predetermined value, to be equal to or greater than a secondary high-frequency pass filter, passing only a high-frequency signal caused by an abnormal discharge.04-09-2009
20110037392LED TRAFFIC SIGNAL WITH SYNCHRONIZED POWER PULSE CIRCUIT - An improved LED traffic signal is provided. The LED traffic signal suitably includes a housing with an opening, a printed circuit board coupled to the housing, and a power supply system coupled to the printed circuit board. The power supply system includes a power supply module that receives an AC input voltage from an AC input line and transforms the AC input voltage into a DC voltage with a regulated current to power the LED load, and a synchronized power pulse circuit connected to the power supply that generates a synchronized power pulse representing a power consumption substantially equivalent to that of a halogen or incandescent traffic signal.02-17-2011
20090251055DISCHARGE LAMP LIGHTING APPARATUS - A discharge lamp lighting apparatus includes a first inverter, a second inverter to output a voltage whose phase is opposite to that of a voltage provided by the first inverter, a discharge lamp connected between a first output terminal of the first inverter and a first output terminal of the second inverter, a first current detection circuit arranged between a second output terminal of the first inverter and a common potential and having a first current detection element and a second current detection element that are connected in series, a second current detection circuit arranged between a second output terminal of the second inverter and the common potential and having a third current detection element and a fourth current detection element that are connected in series, and a protection circuit to detect a current abnormality according to a composite signal of outputs of the second and fourth current detection elements and stop the operation of the first and second inverters.10-08-2009
20090009091LIGHTING UNIT AND DISCHARGE LAMP - Provided is a lighting unit and a discharge lamp each of which is capable of causing a capacitor to break down by heat generated in a heat generating component, so that circuit operation is safely terminated without any additional cost. A compact self-ballasted fluorescent lamp is provided with a lighting unit (01-08-2009
20110043115PWM DIMMING CIRCUIT FOR LED - A PWM dimming circuit for a LED load including a LED load connected to the main LED drive circuit, a current loop configured to measure output current from the LED load, a current loop regulation circuit connected to the current loop, a main control circuit configured to receive a signal from the current loop when the LED load produces an output current, and a PWM dimming controller configured to provide a signal to control the current loop regulation circuit and to make the current loop operate in a closed-loop mode when the LED load produces the output current and to provide a shutdown signal to the main control circuit when the LED load does not produce the output current. When the output current is detected, the main control circuit controls the main LED drive circuit to set its output current at a predetermined load current.02-24-2011
20100001649Electronic Ballast with Lamp End of Life Detection and Protection Circuits - An electronic ballast A includes an inverter circuit for converting a DC voltage into a high-frequency voltage, a resonant circuit which is connected between outputs of the inverter circuit and lights a discharge lamp at a high frequency by a resonant action, a dimming circuit for changing an output voltage to the discharge lamp by changing an operating frequency of the inverter circuit, a DC component detecting circuit for detecting a DC voltage component of the discharge lamp and a control operating circuit which detects an output signal of the DC component detecting circuit for every predetermined period to reduce or stop an output to the discharge lamp in the case where the output signal exceeds a predetermined reference value and to prohibit the protection operation when periodic change amount in the output signal reaches a predetermined value or higher.01-07-2010
20110109230Ballast Circuit for LED-Based Lamp Including Power Factor Correction with Protective Isolation - 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.05-12-2011
20110043114LED Device with Simultaneous Open and Short Detection Function and Method Thereof - An LED device with simultaneous open and short detection function includes a plurality of LED strings, a voltage converter, a current driving unit, a loop control unit, an open detector, a short detector and a voltage detector. The open detector and the short detector are utilized for detecting LED open and LED short for the plurality of LED strings, respectively. The voltage detector is coupled to the open detector, the short detector and the voltage converter, and is utilized for generating a reset signal to the short detector according to an output voltage of the voltage converter when the LED open occurs on the plurality of LED strings, so as to initiate the LED short detection for the plurality of LED strings again.02-24-2011
20090179571Method for Detecting Faults During Operation of High-Pressure Discharge Lamp Using Electronic Ballasts - According to the invention, a state automaton is used when operating a high-pressure discharge lamp on a ballast operated by means of a microprocessor in order to prevent certain malfunctions.07-16-2009
20100033097LAMP ABNORMALITY DETECTING DEVICE AND INVERTER, BACKLIGHT DEVICE, AND DISPLAY DEVICE WHICH ARE EQUIPPED WITH THE SAME - One embodiment of the present invention relates to a lamp abnormality detecting device that detects an abnormality in a lamp. A maximum/minimum extraction circuit outputs, as a maximum current, a current having a maximum current value among currents supplied thereto from lamp drive circuits and outputs, as a minimum current, a current having a minimum current value. A subtraction circuit calculates a difference between the maximum current and the minimum current and outputs an amplified difference as a differential voltage. A comparison circuit compares the differential voltage with a predetermined threshold voltage and outputs a result of the comparison as a control signal. A control circuit stops the operation of the lamp drive circuit when the control signal indicates that the differential voltage is higher than the threshold voltage.02-11-2010
20100033098METHOD AND DEVICE FOR DRIVING A GAS DISCHARGE LAMP02-11-2010
20090153062LIGHT EMITTING DIODE DRIVING DEVICE AND LIGHT SYSTEM - A light emitting diode driving device and light system are provided. The light emitting diode driving device drives a light source by a received alternating current voltage. The light emitting diode driving device includes a rectifier, a feedback unit, a protection unit, a switch unit, a timing unit, and a control unit. The rectifier is electrically coupled to an alternating current voltage source and the light source for providing the alternating current voltage to the light source. The feedback unit is used to detect a loading state and generate a feedback signal according the loading state for outputting the feedback signal. The protection unit is used to receive the feedback signal and compare the feedback signal with a reference voltage built in the protection unit for outputting a switch signal. The switch unit is used to receive the switch signal and connect or disconnect the alternating current voltage source and the light source. Therefore, the protection unit can avoid a burnout due to an exceeding current of the light source.06-18-2009
20100117540METHOD OF DETECTING AN ARC IN A GLOW-DISCHARGE DEVICE AND APPARATUS FOR CONTROLLING A HIGH-FREQUENCY ARC DISCHARGE - In a method of detecting arc discharge in a glow-discharge apparatus GD that has a high-frequency power source PS, a cutting pulse is output for time T05-13-2010
20090261733MONITORING DEVICE - A monitoring device for monitoring at least one fluorescent lamp, particularly in areas at risk of explosion, which fluorescent lamp has a lamp tube with electrodes arranged on the ends thereof in the form of coils, and lamp sockets assigned to said electrodes, is improved for preventing large temperature increases in a corresponding fluorescent lamp, particularly in areas at risk of explosion, by complying with the appropriate explosion safety measure, in that the monitoring device has at least one temperature measuring device assigned to a coil, and one electro-mechanical interruption device with which the energy supply to the fluorescent lamp can be interrupted upon reaching a preset critical temperature value.10-22-2009
20080252219IGNITION CONTROL DEVICE - The invention provides an ignition control device and a killing control device correspond. An ignition control device comprises an ignition circuit module and a killing control device corresponds. The ignition circuit module comprises a killing control device including a killing switch and a timing retard circuit module connected to the ignition circuit module. When the killing control operates, the ignition circuit stops igniting. The invention has following advantages: reasonable structure, low cost, stable control circuit and safe operation and so on.10-16-2008
20090121639CONTROL DEVICE FOR DISCHARGE LAMP - The present invention refers to a driving device of a discharge lamp (05-14-2009
20100001650Lamp End of Life Protection Circuit and Method for an Electronic Dimming Ballast - A electronic ballast includes an inverter circuit for converting a DC voltage into a high-frequency voltage, a resonant circuit connected between outputs of the inverter circuit so as to light a discharge lamp by a resonant action, a control circuit for controlling the inverter circuit, a dimming circuit for continuously changing an output voltage to the discharge lamp by changing an operation frequency in the inverter circuit, a DC component detection circuit and a voltage comparator for detecting whether or not the discharge lamp is at the end of the life at predetermined intervals and outputting an end of life detection signal upon detection of the end of the life state, and a frequency control circuit and a driving circuit for reducing or stopping an output to the discharge lamp by controlling switching elements in response to a life end detection signal inputted from the voltage comparator.01-07-2010
20100259173Electronic ballast protection - An electronic ballast powers at least one fluorescent tube or lamp which has a power source; a DC power supply having an input connected to the power source; an oscillator connected to an output of said DC power supply so as to be driven therefrom; a driver means; and a protection means that deactivates the oscillator when the output reaches a predetermined abnormally high voltage. The protection means includes a transformer; a plurality of windings disposed on the transformer, a delegated winding disposed on the transformer. The protection means includes a sample point for sampling voltage. The protection means deactivates the delegated winding disposed on the transformer for the magnetizing the transformer and stopping oscillation when the sample point reaches a predetermined abnormally high voltage.10-14-2010
20120194076LIGHTING CONTROL DEVICE - The lighting control device provides technology that, by means of a simple configuration, enables the disconnection of a light-emitting element to be detected with high accuracy during PWM dimming. The lighting control device for controlling lighting states of a light-emitting element, includes current supply unit for supplying a current, which is obtained by superimposing a bias current of a predetermined value on a pulse-shaped current whose size periodically fluctuates, to said light-emitting element, and a detection unit which detects a conductive state of said light-emitting element.08-02-2012
20110057567ILLUMINATION DEVICE WITH A SAFETY FEATURE - An illumination device includes a light source, an AC power source and a balance sensing switch. The AC power source is adapted for supplying an alternating current to the light source. The balance sensing switch is connected between the light source and the AC power source for automatically cutting off an electrical connection between the light source and the AC power source when the illumination device topples down.03-10-2011
20100127625Surge Protection Module for Luminaires and Lighting Control Devices - A luminaire can comprise an electronic circuit, such as an LED driver or electronic ballast. A surge protection device in the current path between a power supply and the luminaire components can be configured to protect the electronic circuitry by absorbing and/or redirecting energy of a surge by switching into a low-impedance state while maintaining the protected circuitry (including its internal protective components, if any) in a high-impedance state. The surge protection device can comprise a MOV stage and a filter stage, for example. The surge protection device can be configured as a replaceable module, with the luminaire including an assembly designed to receive the module and allow for easy replacement over the useful life of the other components. Use of fuses or thermal components may cause the surge protection device to interrupt power flow if protection is lost due to internal failure, indicating when module replacement is needed.05-27-2010
20100123398Led based precision approach path indicator - A precision approach path indicator system (PAPI) including multiple LHA indicators and power sources. Each LHA indicator comprises several assembly modules, with each module made up of several red and white LEDs, several collimating lens, one optical combiner, and one projection lens set. From a side view of the module, the red LEDs are placed on top of white LEDs, with a collimating lens in front of each LED. The optical combiner is in front of both the red and white LEDs, slightly above the white LEDs in vertical placement. The optical combiner has a reflective coating on the bottom surface, and a red light filter coating on the projection surface. The combined beam of light is projected out through a projection lens at front of the assembly module.05-20-2010
20120194075LIGHTING DEVICE AND LUMINAIRE - According to one embodiment, a lighting device includes a power supply circuit and a control circuit. The power supply circuit lights a light source. The control circuit determines a threshold based on an output from the power supply circuit to the light source, and controls the power supply circuit to cause a protecting operation to be performed when an output voltage of the power supply circuit deviates from the threshold.08-02-2012
20100194284CIRCUIT ARRANGEMENT FOR OPERATING A CONVERTER - A circuit arrangement for operating a converter, which comprises a bridge circuit having at least a first bridge switch and a second bridge switch and a first bridge center point and a second bridge center point is provided. The circuit arrangement may include a current differential amplifier, the first input of the current differential amplifier being coupled to a first comparison signal input, the second input of the current differential amplifier being coupled to a second comparison signal input, the output of the current differential amplifier being coupled to a control electrode of a first electronic switch.08-05-2010
20100315005BACKLIGHT MODULE WITH DYNAMIC OPEN-LAMP PROTECTION AND RELATED DRIVING METHOD - In order to provide open-lamp protection to a backlight module, a pseudo open-lamp voltage is first generated according to the current flowing through a light source. If the backlight module receives a mode signal corresponding to a high contrast mode, a compensation voltage is added to the pseudo open-lamp voltage for generating a reference voltage. If the reference voltage is larger than a feedback voltage received from an input node of the light source, a driving voltage is outputted to the light source.12-16-2010
20110241550Inrush Current Protection - Methods of protecting an electrical device, such as a ballast, from damage due to an inrush current, and devices incorporating such methods, are disclosed. A loss of input power received by the ballast is detected. In response, the ballast is entered into a standby mode. The ballast is able to remain in the standby mode for a standby period of time. The input power is monitored during the standby period of time to measure a start time. Measurement of the start time is triggered by the ballast receiving input power again. The ballast is entered into an active mode when the measured start time exceeds a protection time. The protection time corresponds to an amount of time needed for an inrush current to dissipate following input power again being received by the ballast, protecting the ballast from possible damage due to the inrush current.10-06-2011
20110084613END-OF-LIFE PROTECTION CIRCUIT AND METHOD FOR HIGH INTENSITY DISCHARGE LAMP BALLAST - An apparatus and method thereof for igniting and operating a high intensity discharge (HID) lamp during an in service life, and powering down the lamp when an end-of-life (EOL) lamp condition is detected. The apparatus and method defines a series of thresholds of lamp voltage asymmetry, or rectification thresholds, and monitors the lamp rectification from ignition through normal operation. The detection scheme is masked off for a predetermined period of time when the lamp is initially started. Thereafter, the rectification threshold of the lamp voltage asymmetry is gradually reduced over time, until a defined minimum rectification threshold level is reached and maintained. The method continuously monitors the lamp voltage and records whenever the lamp voltage asymmetry is higher than the rectification threshold level at any lamp voltage cycle. An EOL lamp condition is determined to exist when a certain number of high asymmetrical cycles occurs in selected total number of lamp voltage cycles during a rolling measurement window.04-14-2011
20110210669END-OF LIFE CIRCUITRY - An LED light bulb which turns itself permanently off when it reaches the end of its useful life, and more particularly, to a scheme which slightly varies the end-of-life condition from unit to unit.09-01-2011
20110068693LIGHTING APPARATUS AND THE METHOD FOR USING THE SAME - A lighting apparatus receives a regulated AC line voltage as an input voltage and comprises a light emitting diode array and a driving circuit. The light emitting diode array is composed of at least one light emitting diode set connected in parallel. The driving circuit has a plurality of outputs corresponding to the light emitting diode sets, and each output has a predetermined value for controlling the brightness of the light emitting diode set. Each light emitting diode set is conducted automatically and in sequence for a fixed time interval based on the output of the driving circuit and the amplitude of the regulated AC line voltage, and is turned off based on the predetermined signal of the driving circuit.03-24-2011
20080231198Circuit for driving and monitoring an LED - Described herein is technology for, among other things, a circuit for controlling a current through an LED. The novel circuit includes a regulator for providing the current to the LED, an LED voltage monitoring circuit for monitoring a voltage drop across the LED and for providing a voltage reading signal based on the voltage drop. The novel circuit further includes a data converter logic circuit coupled with the regulator and the LED voltage monitoring circuit. The data converter logic circuit is operable to control the regulator to adjust the current based on the signal.09-25-2008
20110260624Lighting System Having Photocontrol and Fault Monitoring Capabilities - A photocontroller operates one or more lamps, such as a GU24 compact fluorescent lamp, based on ambient light to provide dusk-to-dawn operation. The photocontroller includes a photosensor for detecting the level of ambient light. The photosensor provides a signal to a photocontrol circuit that controls a switching device to selectively provide power to the lamp based on the level of ambient light detected by the photosensor. A fault detection circuit monitors the level of ambient light and the status of the lamp to determine whether the photocontroller is operating properly. The fault detection circuit determines the status of the lamp based on current flow to the lamp as determined by a current sensor. In addition, the photocontroller can include a processor for performing certain photocontrol and fault monitoring functions.10-27-2011
20120146513LED LAMP - The invention relates to an LED lamp (06-14-2012
20120306373ORGANIC EL ILLUMINATING APPARATUS - Disclosed is an organic EL illuminating apparatus which can detect a short-circuit when the short-circuit is generated in one area between the anode and the cathode. The organic EL illuminating apparatus is provided with: an organic EL illuminating device (12-06-2012
20100096994Error Detector in an Operating Device for Lighting Devices - A control circuit for an operating device for lighting devices, wherein a return signal is supplied to an input of the control circuit by the lighting device, and the control circuit has an error detection block that recognizes at least two different types of lighting device errors by means of the return signal applied at said input.04-22-2010
20100096995DIMMING ELECTRONIC BALLAST WITH LAMP END OF LIFE DETECTION - 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 value04-22-2010
20110156592END OF LAMP LIFE PROTECTION CIRCUIT WITH BI-LEVEL DETECTIONS FOR THE ELECTRONIC BALLAST AND METHOD THEREOF - The configurations of an end of lamp life protection circuit for a ballast and a method thereof are provided in the present invention. The proposed circuit includes a voltage-dividing circuit receiving an input voltage and outputting a first and a second divided voltages and a switch apparatus raising the first divided voltage when the second divided voltage is less than a first pre-determined threshold value and turning off the ballast when the first divided voltage is higher than a second pre-determined threshold value.06-30-2011
20090267520LIGHTING CONTROL DEVICE - A lighting control device includes a current driving portion for DC-controlling or PWM-controlling an LED unit, and a disconnection detection portion for detecting disconnection of the LED unit. The disconnection detection portion has a latch circuit and a reset portion. The latch circuit provides a disconnection detection signal after it is detected that disconnection has occurred for a prescribed time. The reset portion resets the disconnection detection signal based on prescribed conditions.10-29-2009
20110181189LIGHT EMITTING DEVICE AND DRIVING METHOD THEREOF - The light emitting device has a limiter transistor which is connected to a monitoring element, and an inverter an output terminal of which is connected to a gate electrode of the limiter transistor and an input terminal of which is connected to one electrode of the limiter transistor and the monitoring element. In the case where the monitoring element is short-circuited, the limiter transistor can be turned off by the inverter to correct a defect of the monitoring element.07-28-2011
20120161634Light Emitting Module Driving Circuit and Related Method - A light emitting module driver circuit utilized for driving a light emitting module includes a voltage dividing module, a short circuit detection module, and a driving module. A method of performing short circuit protection in the light emitting module driver circuit includes disabling the driving module during a dimming off cycle of the light emitting module driver circuit, enabling the voltage dividing module during the dimming off cycle, dividing a voltage of the light emitting module to generate a divided voltage during the dimming off cycle, and generating a short circuit protection signal according to the divided voltage during the dimming off cycle.06-28-2012
20110204792CURCUIT ARRANGEMENT AND METHOD FOR OPERATING AN OLED - A circuit arrangement for operating an OLED may include a current source to supply the OLED with power; an OLED voltage measuring device configured to provide at its output a signal which is correlated with the voltage dropping across the OLED; an evaluation device configured to provide at its output a first signal if the voltage dropping across the OLED lies above a specifiable threshold value, and to provide a second signal if the voltage dropping across the OLED lies below the specifiable threshold value; an electronic switch having a reference electrode, a working electrode and a control electrode; and at least one ohmic resistor; wherein the series connection of the at least one ohmic resistor and the working electrode-reference electrode section of the electronic switch is connected in parallel with the OLED.08-25-2011
20120074845AUTOMOBILE LED DRIVING DEVICE - An automobile LED driving device includes a current setting portion to set multiple reference currents independently from one another for multiple respective current setting resistors connected externally, a current controller to select one of the multiple reference currents based on a control signal provided from outside, and an output transistor to control an output current to an automobile LED connected externally based on the reference current selected by the current controller.03-29-2012
20100270932FAULT DETECTION AND SHUTDOWN CONTROL CIRCUITS AND METHODS FOR ELECTRONIC BALLASTS - An electronic ballast is capable of inhibiting ballast shutdown caused by erroneously determining a fault condition. The ballast includes a DC power supply circuit for outputting DC power, a power conversion circuit that appropriately converts DC power outputted by the DC power supply circuit and outputs it to a discharge lamp, a DC voltage droop detection circuit for determining existence/absence of a fault condition in the DC power supply circuit 10-28-2010
20120262067BATTERY OPERATED DEVICES - A battery operated device such as a road stud comprises a micro-controller, a battery, and a light source. The micro-controller is configured to operate the battery to provide a train of power pulses to the light source, and each power pulse has a characteristic pulse period and a characteristic duty cycle comprising an on-cycle and an off-cycle. The micro-controller is turned on during the on-cycle and turned into a power saving or sleep mode during the off cycle. Setting the micro-controller into the power saving or sleep mode during the off cycle of the power pulse means substantial battery power saved to extend the operation time per charging of the battery.10-18-2012
20120299482LIGHT EMITTING DEVICE, DISPLAY DEVICE, AND METHOD OF DRIVING ORGANIC ELECTROLUMINESCENT DEVICE - According to one embodiment, there is provided a light emitting device including an organic electroluminescent device that includes a first electrode, a light emitting layer arranged above the first electrode, and a second electrode arranged above the light emitting layer, a drive circuit that supplies a drive current between the first electrode and the second electrode to drive the organic electroluminescent device, and a drive stop circuit that stops the driving of the organic electroluminescent device when a value of the drive current falls below a predetermined value.11-29-2012
20110037393METHOD AND CIRCUIT ARRANGEMENT FOR OPERATING AT LEAST ONE DISCHARGE LAMP - A method for operating a lamp, wherein in the preheating phase a first value of the voltage drop correlated with the reciprocal of the electrical resistance of a coil of the lamp is determined across a resistor at a first instant, and a second value of the voltage drop is determined at a second instant, may include: a) determining the difference between a first and the second value; b) b1) if the difference is greater than a first threshold value: carrying out an algorithm for lamp-type recognition; b2) if the difference is not greater than the first threshold value: c1) if the difference is greater than a second threshold value: d1) if the second value is greater than a third threshold value: determining a coil short circuit; d2) if the second value is not greater than the third threshold value: operating the lamp with the current set of operating parameters.02-17-2011
20110037391Power Supply Control Device for Lamp - A power supply control device for lamp includes a control unit, the control unit receives a forward voltage signal and a reverse voltage signal simultaneously from a zero-crossover sampling circuit and determines if a connected load is an LED lamp, then the control unit turns on a tri-electrode AC switch (TRIAC) after an operating voltage for the LED voltage is reached, thereby outputting the AC power to an outlet for illuminating the LED lamp; since the TRIAC can be turned on with the forward voltage or the reverse voltage, the LED lamp is powered with a stable power supply to prevent the LED lamp from blinking.02-17-2011
20120286667LED DRIVING CIRCUIT AND PROTECTING CIRCUIT THEREOF - An LED driving circuit for driving an LED module is provided. The LED module is coupled to an inductor and a flywheel unit to provide a continuous current conduction of the inductor. A terminal of a converting switch is coupled to the LED module, and another terminal thereof is coupled to ground through a current detection unit that generates a current feedback signal to a controller, so as to stabilize a current flowing through the LED module. The LED driving circuit also includes a protecting circuit, which detects a potential of one end of the LED module to generate a detection signal and makes/has the converting switch to be turned off responsive to the detection signal. If the converting switch is turned off, driving of the LED module is stopped.11-15-2012
20100181917METHOD FOR DRIVING A LIGHT SOURCE, DRIVING APPARATUS FOR DRIVING THE LIGHT SOURCE AND LIQUID CRYSTAL DISPLAY APPARATUS HAVING THE DRIVING APPARATUS - According to one or more embodiments, an inverter provides a light source with an input voltage. A protection circuit shuts down the inverter based on an overvoltage protection level that is detected based on the input voltage. A protection circuit control part shuts down the operation of the protection circuit during a predetermined interval. Abnormal operation of the protection circuit caused by a high voltage provided when the light source is turned on may be prevented. Therefore, a turn-on defect of the light source may be prevented.07-22-2010
20100090604LED DRIVE CIRCUIT, LED ILLUMINATION COMPONENT, LED ILLUMINATION DEVICE, AND LED ILLUMINATION SYSTEM - An LED drive circuit is an LED dive circuit that receives an alternating voltage to drive an LED, and includes a current remove portion that removes a current from a current supply line that supplies an LED drive current to the LED. If an input current to the LED drive circuit is an unnecessary current, the LED does not light because of current removal by the current remove portion. If the input current to the LED drive circuit turns into the LED drive current from the unnecessary current, the current remove portion decreases the amount of current removed.04-15-2010
20110273095FREQUENCY CONVERTED DIMMING SIGNAL GENERATION - There is provided a lighting control circuit comprising a duty cycle detection circuit, an averaging circuit, a waveform generator and a comparator circuit. The duty cycle detection circuit generates a first periodic waveform having a duty cycle and frequency corresponding to an input waveform duty cycle and frequency. The averaging circuit generates a first signal having a voltage level corresponding to the duty cycle of the first periodic waveform. The waveform generator outputs a second periodic waveform having a frequency different from the input waveform frequency. The comparator circuit compares the second periodic waveform with the first signal to generate an output waveform having a duty cycle corresponding to the input waveform duty cycle and a frequency corresponding to the frequency of the second periodic waveform. Also, there are provided methods.11-10-2011
20130134882Universal-Voltage Self-Heating Thermal Detector - A self-heating thermal protector operates to disconnect a load control device for a lighting load from an AC power source when insulation is present around the insulation detector independent of the magnitude of an AC mains line voltage of the AC power source. The insulation detector comprises a temperature-sensitive switch and a constant power circuit that are located in a thermally-conductive enclosure. The temperature-sensitive switch is coupled between the AC power source and the load control device and is rendered conductive and non-conductive in response to a temperature inside the enclosure. The constant power circuit is coupled in parallel with the AC power source and dissipates a constant amount of power independent of the magnitude of the AC mains line voltage when the temperature-sensitive switch is conductive. Restricted airflow over the thermal protector causes the temperature inside the enclosure to increase, such that the temperature-sensitive switch is rendered non-conductive.05-30-2013
20130147353LIGHT SOURCE PACKAGE - A light source package for selectively interrupting power to a light source is provided. An optical element is positioned to reflect a reflected portion of the light from the light source. The reflected portion impinges upon a base that includes a roof panel with a light source side and a sensor side that is opposite to the light source side. The light source side of the roof panel receives the reflected portion of the light and transmits a transmitted portion of the light through the roof panel. The sensor side of the roof panel includes a recess in which a sensing component is located. The sensing component receives the transmitted portion of the light and is be configured to interrupt power to the light source when the transmitted portion of the light is below a threshold.06-13-2013
20130147354ILLUMINATION CONTROLLING CIRCUIT AND ILLUMINATION SYSTEM - The invention discloses an illumination controlling circuit coupled between a household electricity input and an illumination lamp. The illumination controlling circuit includes a dimmer module, a sampling-and-holding circuit, a differential circuit, an integrator circuit and a clamping circuit. The dimmer circuit is used for generating a dimming signal which includes a plurality of waveform pulses. The sampling-and-holding circuit samples from the dimming signal, so as to obtain an average waveform pulse. The differential circuit is used for extracting a voltage difference of the average waveform pulse. The integrator circuit performs integration on the average waveform pulse according to the voltage difference, so as to generate a direct current voltage signal. When a level of the direct current voltage signal exceeds a threshold voltage level of the clamping circuit, the direct current voltage signal is used for driving the illumination lamp.06-13-2013
20100308733APPARATUS AND METHOD FOR CONSTANT POWER OFFLINE LED DRIVER - A single-stage integrated circuit drives LED sources in a constant power mode to eliminate the need for LED current sensing, while reshaping the waveform of the inductor current near line zero crossing to achieve high power factor. The integrated circuit achieves substantially constant input power my maintaining a constant voltage at a power factor corrector controller through an input voltage feedforward system. Accordingly, the disclosed circuit provides a high power factor, high efficiency, simple, and cost-effective solution with substantially consistent input power for both isolated and non-isolated offline LED applications.12-09-2010

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