Abstract: A Direct Current, DC, voltage source arranged for providing a DC voltage based on an input voltage between two input terminals, wherein said DC voltage source comprises a transformer arranged for receiving a supply current, at a first side of the transformer, and for transforming said supply current to a circulating current at a second side of the transformer, a first and a second input terminal for receiving an input voltage for setting a DC voltage to be provided by said DC voltage source, a first diode, wherein an anode of said first diode is connected to a first end of said second side of said transformer, and wherein a cathode of said first diode is connected to said first input terminal, a current regulator circuit for assuring that an amount of current circulating current is shunted from the first diode.

Abstract: A double ended retrofit LED lighting device having two connecting terminals (L1, L2) at a first end for connection to a power source and two further connecting terminals (R1, R2) at a second end for further connection to said power source, the LED lighting device comprising: —at least one LED (D1) for emitting light, —an LED driver arranged for receiving an AC current from said power source and for driving said at least one LED based on said received AC current, —a filament circuit (RfilL) connected between said two connecting terminals (L1, L2) for supporting a filament current circulating back to said power source for indicating a presence of said LED lighting device to said power source, and—a pin-safety circuit comprising two pin-safety switches (SwLa, SwLb), wherein each pin-safety switch is connected to a respective separate terminal of said two connecting terminals (L1, L2) and comprises a changeover contact, wherein said changeover contact comprises: —a central node (CC) arranged to be connected to sa

Abstract: An LED driver for an LED lamp, which also comprises an LED load. The LED driver is adapted to connect to an input source at a first and second terminal. The LED driver comprises a switching arrangement configured to enable a controller to control at least a magnitude and phase of the voltage between the first and second terminals. The phase of the voltage between the first and second terminals may be defined to control an amount of power that flows from the input source to power the LED lamp.

Abstract: A Direct Current, DC, voltage source arranged for providing a DC voltage based on an input voltage between two input terminals, wherein said DC voltage source comprises a transformer arranged for receiving a supply current, at a first side of the transformer, and for transforming said supply current to a circulating current at a second side of the transformer, a first and a second input terminal for receiving an input voltage for setting a DC voltage to be provided by said DC voltage source, a first diode, wherein an anode of said first diode is connected to a first end of said second side of said transformer, and wherein a cathode of said first diode is connected to said first input terminal, a current regulator circuit for assuring that an amount of current circulating current is shunted from the first diode.

Abstract: An LED driver that is operable with two different types of power source originally designed for a high-intensity discharge lamp. The LED driver directs current of an input power provided by the power source down a first current path if it is determined that the power source comprises a functional ignitor. The LED driver directs current of an input power provided by the power source down a second current path if it is determined that the 5 power source does not comprise a functional ignitor.

Abstract: A device for determining a type of a power source for powering a LED lighting unit, wherein one possible type comprises a ballast originally designed for a high intensity discharge lamp and repurposed for use with an LED lighting unit. The power source type determiner monitors at least one electrical parameter of either a load or the power source itself after a power drawn by the load whose characteristic is set to a critical value. A value of the electrical parameter is used to identify a type of the power source. A value of the electrical parameter is the pulse generated by the traditional ballast for gas discharge lamp, which pulse is detected to determine the type of the power source.

Abstract: An LED driver for an LED lamp, which also comprises an LED load. The LED driver is adapted to connect to an input source at a first and second terminal. The LED driver comprises a switching arrangement configured to enable a controller to control at least a magnitude and phase of the voltage between the first and second terminals. The phase of the voltage between the first and second terminals may be defined to control an amount of power that flows from the input source to power the LED lamp.

Abstract: A double ended retrofit LED lighting device having two connecting terminals (L1, L2) at a first end for connection to a power source and two further connecting terminals (R1, R2) at a second end for further connection to said power source, the LED lighting device comprising: —at least one LED (D1) for emitting light, —an LED driver arranged for receiving an AC current from said power source and for driving said at least one LED based on said received AC current, —a filament circuit (RfilL) connected between said two connecting terminals (L1, L2) for supporting a filament current circulating back to said power source for indicating a presence of said LED lighting device to said power source, and—a pin-safety circuit comprising two pin-safety switches (SwLa, SwLb), wherein each pin-safety switch is connected to a respective separate terminal of said two connecting terminals (L1, L2) and comprises a changeover contact, wherein said changeover contact comprises: —a central node (CC) arranged to be connected to sa

Abstract: An LED driver that is operable with two different types of power source originally designed for a high-intensity discharge lamp. The LED driver directs current of an input power provided by the power source down a first current path if it is determined that the power source comprises a functional ignitor. The LED driver directs current of an input power provided by the power source down a second current path if it is determined that the 5 power source does not comprise a functional ignitor.

Abstract: A circuit is for generating a DC voltage supply from a higher voltage AC signal. A first capacitor (C1) is in series between an input (12) and a first node (N1), a first diode (D1) is in forward direction between the first node and a DC voltage supply node (Nout), a second capacitor (C2) is between the DC voltage supply node and a reference terminal, and a second diode (D2) is in forward direction between the reference terminal and the first node. This defines a general charge pump architecture. A third capacitor (C3) is then provided between the first node and a second node (N2) and a controllable voltage supply (60) defines the voltage at the second node (N2). This adjustable node voltage improves the efficiency of the circuit, in that excess current can be dissipated efficiently, and it can be implemented with a simple circuit.

Abstract: A device for determining a type of a power source for powering a LED lighting unit, wherein one possible type comprises a ballast originally designed for a high intensity discharge lamp and repurposed for use with an LED lighting unit. The power source type determiner monitors at least one electrical parameter of either a load or the power source itself after a power drawn by the load whose characteristic is set to a critical value. A value of the electrical parameter is used to identify a type of the power source.

Abstract: A circuit is for generating a DC voltage supply from a higher voltage AC signal. A first capacitor (C1) is in series between an input (12) and a first node (N1), a first diode (D1) is in forward direction between the first node and a DC voltage supply node (Nout), a second capacitor (C2) is between the DC voltage supply node and a reference terminal, and a second diode (D2) is in forward direction between the reference terminal and the first node. This defines a general charge pump architecture. A third capacitor (C3) is then provided between the first node and a second node (N2) and a controllable voltage supply (60) defines the voltage at the second node (N2). This adjustable node voltage improves the efficiency of the circuit, in that excess current can be dissipated efficiently, and it can be implemented with a simple circuit.

Abstract: A control circuit, of a control loop, for a lighting driver. The lighting driver is adapted to controllably connect an electronic ballast to an LED light source or lamp. The control circuit comprises a biasing circuit having an adjustable impedance. A tuning circuit adjusts the impedance of the biasing circuit so as to tune a parameter of a frequency response of the control loop and thereby of the lighting driver.

Abstract: A switch mode power converter has a transformer for isolating the output and an opto-isolator for providing both voltage and current feedback. A light source of the opto-isolator is in series between first and second adjustment signals, wherein one is based on current sensing and the other is based on voltage sensing. A light detector of the opto-isolator provides an isolated feedback signal for controlling the converter.

Abstract: A control circuit, of a control loop, for a lighting driver. The lighting driver is adapted to controllably connect an electronic ballast to an LED light source or lamp. The control circuit comprises a biasing circuit having an adjustable impedance. A tuning circuit adjusts the impedance of the biasing circuit so as to tune a parameter of a frequency response of the control loop and thereby of the lighting driver.

Abstract: The invention relates to a light emitting device (2) for retrofitting a fluorescent lamp comprising two sets of connecting pins (21, 23, 21?, 23?) for connecting the light emitting system (1) to a lighting fixture, one first (611) and one second (613) filament unit, encapsulated in a bulb and fed through it, electrically coupled to the connecting pins (611, 613) and a solid state light source connected between the filament units.

Abstract: A lighting device is configured to receive a first voltage signal, and includes: a first circuit coupled to input terminals for receiving the first voltage signal, the first circuit including: rectifying diodes for rectifying the first voltage signal and supplying a second voltage signal, a first capacitor for buffering the second voltage signal, and a second capacitor coupled in parallel to one of the rectifying diodes of the first circuit; a second circuit receiving an input voltage signal, corresponding to the second voltage signal, and converting the input voltage into an output signal; and a light circuit receiving the output signal of the second circuit and including at least one light emitting diode, wherein the first circuit includes a fourth circuit in parallel to the second capacitor, the fourth circuit including at least two fourth circuit diodes and being connected by a fourth capacitor to one of the input terminals.

Abstract: This invention discloses a method and apparatus managing a voltage applied to a load. The method comprises determining generation of an electrical arc, the electrical arc being determined based on detecting a high frequency signal; isolating and filtering the high frequency arc signal; generating a signal having a frequency proportional to the frequency of the arc signal; and altering a frequency of the voltage applied to the load in response to the frequency of the signal.

Abstract: Lighting device suitable for multiple voltage sources, comprising a first circuit (1) with diode circuits coupled to input terminals (2, 3) for receiving first voltage signals from first circuits (21) such as voltage-to-voltage converters. The diode circuits comprise diodes (11-14) for rectifying the first voltage signals and are coupled to output terminals (4, 5) for supplying second voltage signals. First capacitors (15) are coupled to the output terminals (4, 5) for buffering the second voltage signals and for offering buffered second voltage signals to second circuits (22) such as voltage-to-current-converts for feeding light circuits (30) comprising one or more light emitting diodes. Second capacitors (16, 17) coupled in parallel to one of the diodes (11-14) provide a charge-pump effect to improve performances of the first and second circuits (21, 22) and the light circuits (30).

Abstract: The present invention provides a lamp driving circuit. When it is used to drive a number of lamps arranged in a hybrid serial-parallel configuration, the lamp driving circuit eliminates the parasitic current in series branch circuits by using an inverse transformer, which makes the current passing each of the lamps in each of the series branch circuits consistent and consequently eliminates the imbalance of each of the lamps.