Osram Sylvania Inc.

Osram Gmbh

Osram Ag

Warren Paul Moskowitz

Joseph Allen Olsen

Philip E Moskowitz

Joachim Muehlschlegel

Norwin Von Malm

Bernhard Siessegger

Marijan Kostrun

Lori R Brock

Joachim Mühlschlegel

Nanu Brates

Hubert Maiwald

P Bruce Newell

Techniques and corresponding circuitry are disclosed for providing active current sharing in lighting applications. In some embodiments, an active current sharing circuit is provided that includes a series-pass sub-circuit, such as a transistor or transistor circuit (or other active series-pass circuit), for each LED string. In addition, each string has a current sense sub-circuit for sensing current of that string. A monitor and control sub-circuit operates in conjunction with the series-pass sub-circuit to maintain the sensed current equal to a common reference level. In some embodiments, the common reference level is controlled to maintain the lowest series-pass element voltage close to or equal to zero volts (&#x2212;0.25 VDC to +0.25 VDC).

Current sharing circuit for LED lighting

An optoelectronic component device includes a first group of optoelectronic components including at least one first optoelectronic component, wherein the at least one first optoelectronic component provides electromagnetic radiation of a first color valence, a second group of optoelectronic components including at least one second optoelectronic component, wherein the at least one second optoelectronic component provides electromagnetic radiation of a second color valence, and a phase dimmer, wherein the phase dimmer is designed in such a way that a first operating mode and a second operating mode are provided, wherein the phase dimmer actuates the first and the second group of optoelectronic components in such a way that, in the first operating mode, a first array of optoelectronic components of the optoelectronic component device is energized and, in the second operating mode, a second array of optoelectronic components of the optoelectronic component device is energized.

Optoelectronic component device

A system for directly driving light emitting diodes (LEDs). A string of LEDs is coupled across an input voltage and includes a plurality of separate groups of LEDs. Each of a plurality of switches is coupled in parallel with an associated one of the groups of LEDs for controlling current flow through the associated group of LEDs in response to a control signal from a controller circuit. A switch protection circuit is associated with at least one of the switches. The switch protection circuit is configured to place the switch into a conducting state in the event of failure of an LED in the associated group of LEDs.

Directly driven high efficiency LED circuit

A device, system and method to drive light emitting diodes (LEDs) are disclosed. An exemplary system may include a string of LEDs coupled across a voltage source configured to provide an input voltage. The string of LEDs may include a plurality of separate groups of LEDs and a plurality of switch circuits. Each of the switch circuits may include a switch coupled in parallel with an associated one of the groups of LEDs to control current flow through the associated group of LEDs in response to a control signal from a controller circuit. A switch protection circuit may be associated with at least one of the switches. A steering circuit may also be coupled in series and associated with each of the groups of LEDs.

High efficiency, low energy storage driver circuit for solid state light sources

A system and method including self oscillating feedback for acoustic operation of a discharge lamp. The system includes a ballast configured to receive a modulation input and modulate a lamp power signal in accordance with the modulation input. A photodetector senses the optical output of the lamp to provide an electrical feedback to a feedback circuit. The feedback circuit filters the feedback to couple a portion thereof corresponding to a selected acoustic resonance mode of the lamp to the ballast as the modulation input thereby causing self-oscillation at the selected acoustic resonance mode.

System and method including self oscillating feedback for acoustic operation of a discharge lamp

A circuit arrangement for supplying a lamp wattage on a high-pressure gas discharge lamp in the form of an alternating current having an operating frequency, said operating frequency being frequency-modulated within large limits such that no acoustic resonances are embodied in the lamp. Amplitude modulation through the frequency response of an interface is compensated by modulating an amplitude of a supply voltage.

Circuit arrangement and method for the operation of high-pressure gas discharge lamps

An LED reflector lamp is provided wherein the lamp has a concave reflector substantially symmetrically arrayed about an axis, the reflector further having a focus and a bottom. A subassembly is coaxially aligned with said axis and comprises a light guide having a proximal end positioned outside of said reflector and a distal end positioned within said reflector at said focus. A first light source comprising at least one light emitting diode (LED) is positioned at said proximal end and operable to emit a first radiation when energized. A second light source comprising at least one phosphor is positioned at said distal end and operable to emit a second radiation having a different wavelength than said first radiation when energized by said first radiation from said first light source.

LED reflector lamp

An electronic control gear for a HID lamp receives an input signal for operating the lamp and frequency modulates the input signal to generate a frequency modulated output signal that drives an arc of the lamp. The frequency modulation of the output signal sweeps continuously between a low frequency modulation and a high frequency modulation, the low frequency modulation being a frequency fin a range of 125 kHz to 150 kHz and the high frequency modulation being a frequency fin a range of 230 kHz to 300 kHz, where ffis at least 0.4*f. A power amplifier changes an amplitude of the frequency modulated output signal during the low frequency modulations so that a current amplitude of the frequency modulated output signal is substantially constant, and a variable gain transformer adjusts a voltage of the frequency modulated output signal during starting of the lamp.

Frequency modulation method and device for high intensity discharge lamp

An electronic control gear for a HID lamp receives an input signal for operating the lamp and frequency modulates the input signal to generate a frequency modulated output signal that drives an arc of the lamp. The frequency modulation of the output signal sweeps continuously between a low frequency modulation and a high frequency modulation, the low frequency modulation being a frequency fin a range of 125 kHz to 150 kHz and the high frequency modulation being a frequency fin a range of 230 kHz to 300 kHz, where f-fis at least 0.4*f. A power amplifier changes an amplitude of the frequency modulated output signal during the low frequency modulations so that a current amplitude of the frequency modulated output signal is substantially constant, and a variable gain transformer adjusts a voltage of the frequency modulated output signal during starting of the lamp.

An arc discharge lamp () has a lamp envelope () and an arc discharge vessel () mounted within the envelope (). An arc centering structure () is positioned within the arc discharge vessel for substantially centering the arc. The centering structure () is preferably fixedly mounted within the arc discharge vessel () and preferably comprises a metal annulus () that incandesces during lamp operation and adds to the light output of the lamp. In a preferred embodiment, the lamp is suitable for vertical or horizontal operation.

Arc discharge vessel having arc centering structure and lamp containing same

A circuit () for powering a high intensity discharge lamp () comprises first and second input terminals (), first and second output terminal (), first and second inverter switches (SW,SW), a transformer (), first and second buck capacitors (C,C), first and second low-side capacitors (C,C), an ignitor (), and a diode subcircuit (). Transformer () includes a primary winding () and a secondary winding (). During operation of circuit, primary winding () functions as a buck inductor, while secondary winding () operates in conjunction with diode subcircuit () to provide enhanced low frequency open circuit voltage (OCV) during the lamp starting phase and during steady-state powering of the lamp (). Circuit () also allows for a lamp current having a non-zero average value. Circuit () is realizable with first and second low-side capacitors (C,C) having a relatively low capacitance value.

Circuit for powering a high intensity discharge lamp

The arc of an alternating current discharge lamp may be magnetically straightened by including a small direct current component to the lamp current. The lamp may then be operated substantially as an alternating current lamp, but with out the need to synchronize the magnetic field with the alternating lamp current. The minor inclusion of the direct current component enables the lamp to be magnetically deflected effectively for arc straightening, optical positioning of the arc, offset positioning from the envelope wall to preserve lamp life, and other useful functions.

Magnetically deflected arc lamp

A system and method for the operation of a mercury free high intensity discharge lamp is disclosed which provides lamp longevity and improved photometric results regardless of the orientation of the lamp. To this end, an acoustically modulated ballast without off-time and low power time is supplied to the lamp.

System for and method of operating a mercury free discharge lamp

An AC discharge lamp having a constricted arc, and powered through a unidirectional ballast with a unidirectional current, is described. The AC lamp operates as a DC lamp. One method of achieving the constriction of the arc of this lamp is to modulate the DC input power to the discharge lamp to reduce the adverse effects of DC operation. The mechanism mixes the chemicals with an acoustically induced flow.

Method of DC operation of a discharge lamp with ARC stabilization

Methods of operating a discharge lamp by amplitude-modulating and pulsing the lamp input power waveform. The techniques control both the arc stabilization and color characteristics of the lamp, respectively. The alternating current (AC) input waveform is amplitude-modulated to stabilize the arc with a swept AC periodic wave (such as a sine wave, sawtooth wave, square wave, etc., or a combination thereof). The swept wave can be generally swept from about 20 kHz to 60 kHz, with a preferable band sweep of from approximately 40 kHz to 50 kHz. The sweep can also be patterned (such as allowing the sweep to have stepped rises and falls within the sweep cycle). The sweep may also contain multiple-frequency sweeps that are bundled together to modulate the carrier wave. These modulation forms are used to center, constrict and stabilize the arc. In addition to this stabilization, the lamp input waveform is pulsed to control and regulate the color characteristics of the lamp.

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Ipswich, MA, United States of America

Warren Paul Moskowitz