Patent application number | Description | Published |
20130187549 | LED AC DRIVING CIRCUIT CAPABLE OF ADJUSTING OPERATING VOLTAGE - An LED AC driving circuit capable of adjusting operating voltage has a rectifying unit, an LED unit, a voltage-controlled transistor, a current detecting unit and a current regulating unit to form a power loop. Further, a resistance adjusting unit is connected to the voltage-controlled transistor in parallel. The current regulating unit detects the operating power of the voltage-controlled transistor. When the detected operating power is zero, the resistance of the resistance adjusting unit is increased for increasing the current flowing through the voltage-controlled transistor. When the detected operating power becomes larger than a maximum rated power, the resistance of the resistance adjusting unit is decreased to reduce the current. Thus, the operating power is maintained between zero and the maximum rated power. | 07-25-2013 |
20130187555 | Flicker-Free LED Driver Circuit with High Power Factor - A flicker-free LED driver circuit with a high power factor has a rectifying unit connected with an AC power source, an LED module connected in series with the rectifying unit, a capacitor module connected in parallel with the LED module, and a constant current circuit connected in series with the LED module and the capacitor module. When the voltage output by the rectifying unit is smaller than a junction voltage of the LED module, the capacitor module discharges to the LED module so that the LED module does not go out, thereby eliminating the flickering. The input impedance of the rectifying unit can be regarded as a capacitive reactance element connected in parallel with a nonlinear resistive element. The internal resistance of the constant current source approaches infinity. Therefore, the power factor of the flicker-free LED driver circuit approximates 1, achieving a high power factor. | 07-25-2013 |
20130200799 | High-Voltage AC LED Driver Circuit - A high-voltage AC LED driver circuit has a rectifier unit, an LED unit, a voltage-controlled transistor, a current detection unit, a control unit and a shunt unit. The shunt unit has a current limiting transistor for limiting a current flowing through the shunt unit to be lower than the working current. The current flowing through the voltage-controlled transistor will be higher than 0 (A) although an AC voltage is boosted. In addition, the voltage-controlled transistor can extend its working voltage and is prevented from being over heated. | 08-08-2013 |
20130222965 | Arrester - An arrester includes a switch and a lightning detection breaker connected to the switch. The lightning detection breaker includes a metal conducting terminal electrically connected to an earth return, a DC power supply terminal, a ground terminal and an output terminal. When the power supply is under a lightning strike, a potential difference of both the DC power supply terminal and the ground terminal of the lightning detection breaker will go up to several thousands of volts. However, a voltage of the metal conducting terminal will not go up because the metal conducting terminal is electrically connected to the earth return. The switch will automatically become open circuit by the lightning detection breaker, and therefore an electronic device connected to the arrester is protected from damage done by the lightning. | 08-29-2013 |
20130257294 | ILLUMINATING APPARATUS AND CONTROL METHOD FOR KEEPING A CONSTANT TOTAL BRIGHTNESS OF AMBIENT LIGHT AND LIGHT PRODUCED BY THE ILLUMINATING APPARATUS - An illuminating apparatus and control method is adapted to keep a constant total brightness of the ambient light and light produced by the illuminating apparatus. The illuminating apparatus has a control module storing an objective brightness and detect the ambient brightness through an optical sensor. The control module turns on a lamp according to a comparison result of the objective brightness and the ambient brightness. Hence, a total brightness of the lamp's brightness and the ambient brightness is adjustable to be equally bright as the objective brightness. The illuminating apparatus of the invention does not provide excessive brightness and accordingly conserves electric power energy. | 10-03-2013 |
20130313991 | FLICKER-FREE LINEAR LED DRIVER CIRCUIT WITH HIGH POWER FACTOR - The flicker-free linear LED driver circuit with high power factor has a rectifier unit, an LED unit, a constant current unit, a storage capacitor and a voltage controlled transistor; the rectifier unit is connected to an AC power and converts the AC power into a pulsating DC power; the LED unit is connected to the rectifier unit and has multiple LED sources; the constant current unit is connected in series with the LED unit to form a first power circuit; wherein current flowing in the LED unit is fixed to a constant value by the constant current unit; the storage capacitor is connected to the rectifier unit; the voltage controlled transistor is connected in series with the storage capacitor to form a second power circuit; wherein the voltage controlled transistor limits current flowing in the storage capacitor under a maximum current limit value. | 11-28-2013 |
20140028203 | LED DRIVER CIRCUIT - A high efficiency AC LED driver circuit has a rectifier unit, an LED light string, multiple voltage controlled transistors, a current detection unit, and a power efficiency control unit. The rectifier unit is connected to an AC power and converts the AC power into a pulsating DC power. The LED light string is connected to the rectifier unit and has multiple LED units. The voltage controlled transistors are respectively and electrically connected to each LED unit and form multiple shunt circuits. The current detection unit is electrically connected to the voltage controlled transistors. The power efficiency control unit is electrically connected to the current detection unit, series nodes between the LED units and the control terminals of the voltage controlled transistors; wherein the power efficiency control unit adjusts loop current based on a voltage drop of each LED unit. | 01-30-2014 |
20140055175 | High-Voltage Driver Integratable with an Integrated Circuit - A high-voltage driver integratable with an integrated circuit has a switching transistor, a switching diode, a first resistor, a second resistor, and a control transistor. The anode of the switching diode is connected to the source of the switching transistor. The cathode of the switching diode is connected to the gate of the switching transistor. When the source voltage of the switching transistor is far greater than the cut-in voltage of the switching diode, the switching diode is forward-biased, and the gate-source voltage of the switching transistor is equal to the negative cut-in voltage. Accordingly, high voltage will not be generated across the gate-source junction of the switching transistor, no junction breakdown will occur between the gate and source thereof, and the high-voltage driver can be integrated with an integrated circuit. | 02-27-2014 |
20140062323 | Linear Light-Emitting Diode Driving Circuit with Voltage-Lowering Serial Capacitor - A linear light-emitting diode (LED) driving circuit with voltage-lowering serial capacitor has a rectification unit, an LED unit, a constant current controller, a series and parallel voltage divider and a controller. The controller is built in with a safe voltage threshold, controls the series and parallel voltage divider to be connected in series to the LED unit when an output voltage of the rectification unit exceeds the safe voltage threshold, ensuring that an average voltage across the LED unit and the constant current controller is stable, and controls the series and parallel voltage divider to be parallelly connected across the LED unit and the ground when the output voltage of the rectification unit does not exceed the safe voltage threshold. Accordingly, a safety standard of voltage for LED driving circuit can be secured and users' safety can be ensured. | 03-06-2014 |
20140159592 | LED LIGHT TUBE COMPATIBLE WITH LIGHT FIXTURE HAVING ELECTRONIC BALLAST OR MAGNETIC BALLAST - The LED light tube compatible with a light fixture having an ballast has a translucent tube and an LED light bar mounted in the translucent tube. and having at least one waveform conversion circuit having multiple rectifier diodes and at least one LED light string connected to the at least one waveform conversion circuit, wherein a recovery time of each rectifier diode is under 1 μs; the ballast determines the at least one waveform conversion circuit and the at least one LED light string as low impedance loads, thus, the ballast does not output a high voltage AC power and burn the LED light tube; a recovery time of each rectifier diode is also short such that the LED light tube can endure a high frequency AC power outputted by the ballast. As such, the LED light tube is compatible with the light fixture. | 06-12-2014 |
20140197748 | LED Lighting Tube - The LED lighting tube that is compatible with an electronic ballast has two snubber circuits, a waveform conversion circuit, and at least one LED light string. The snubber circuits are connected to terminals of the LED lighting tube, and input terminals of each snubber circuit are connected to electrode pins of a corresponding terminal, and each snubber circuit has at least one resistor connected in series between the electrode pins of the corresponding terminal. The waveform conversion circuit has multiple rectifier diodes, wherein input terminals of the waveform conversion circuit are respectively connected to output terminals of the snubber circuits, wherein a recovery time of each rectifier diode is under 2.5 us. Two ends of the at least one LED light string are respectively connected to output terminals of the waveform conversion circuit, wherein each one of the at least one LED light string comprises multiple LED units connected in series. | 07-17-2014 |
20140239814 | LIGHT-EMITTING DIODE LAMP COMPATIBLE WITH AN ELECTRONIC BALLAST GENERATING PREHEATING CURRENT - An LED lamp has two preheating current control units respectively connected to a first electrode terminal and a second electrode terminal of the LED lamp, two lamp-side rectification circuits, and an LED light string. Each preheating current control unit has a ballast-side rectification circuit connected to one of the first and second electrode terminals and a load-varying circuit having a resistive load and a control circuit. The resistive load is serially connected to a DC output terminal of the ballast-side rectification circuit through the control circuit. The control circuit adjusts a resistance of the resistive load. Two input terminals of each lamp-side rectification circuit are respectively connected to one of the electrodes of each of the first electrode terminal and the second electrode terminal. The LED light string has two ends respectively connected to the two output terminals of each lamp-side rectification circuit, and has multiple series-connected LED elements. | 08-28-2014 |
20150049473 | LED TUBE HAVING LONG INTERNAL CREEPAGE DISTANCES - An LED tube has a tube body, an LED light board and two caps. The tube body has a translucent tube shell and a heat dissipating seat. The translucent tube shell has two openings, a gap, two side walls separated by the gap, two first slide tracks and two second slide tracks. The heat dissipating seat is mounted in the gap and has two opposite sides respectively mounted in the two first slide tracks. The LED board abuts the heat dissipating seat and has two opposite sides respectively mounted in the two second slide tracks. The sides of the heat dissipating seat and the sides of the LED light board are separated by the first and the second slide tracks to extend creepage distances between the heat dissipating seat and the LED light board, and further avoid a short circuit between the heat dissipating seat and the LED light board. | 02-19-2015 |
20150049474 | LED TUBE HAVING LONG INTERNAL CREEPAGE DISTANCES - An LED tube has a tube body, an LED light board and two caps. The tube body has a translucent tube shell and a heat dissipating seat. The translucent tube shell has two openings and a gap. The heat dissipating seat is mounted in the gap. The LED light board is mounted in the tube body and has a luminous surface, wherein two opposite ends of the LED light board extend out of the heat dissipating seat. The luminous surface has four electrical connecting parts, wherein each two electrical connecting parts are respectively mounted near a corresponding one of the two opposite ends, thus, the four electrical connecting parts are mounted away from the heat dissipating seat to extend internal creepage distances between the four electrical connecting parts and the heat dissipating seat, and further increase electrical safety of the LED tube. | 02-19-2015 |