Abstract: An electronic ballast with dimming circuit including an electronic ballast dimming circuit receiving an analog dimming signal, the electronic ballast dimming circuit including an input dimming circuit (210) operable to receive the analog dimming signal (252) at an analog dimming signal input (212); and an output dimming circuit (220) operably connected to the input dimming circuit (210), the output dimming circuit (220) being operable to receive a fixed frequency signal (222) having a variable duty cycle and to generate an analog dimming control signal (224) in response to the analog dimming signal (252). Output voltage at the analog dimming signal input (212) is a function of the variable duty cycle of the fixed frequency signal (222) when the analog dimming signal (252) is not present at the analog dimming signal input (212).

Abstract: An electronic ballast with dimming circuit including an electronic ballast dimming circuit receiving an analog dimming signal, the electronic ballast dimming circuit including an input dimming circuit (210) operable to receive the analog dimming signal (252) at an analog dimming signal input (212); and an output dimming circuit (220) operably connected to the input dimming circuit (210), the output dimming circuit (220) being operable to receive a fixed frequency signal (222) having a variable duty cycle and to generate an analog dimming control signal (224) in response to the analog dimming signal (252). Output voltage at the analog dimming signal input (212) is a function of the variable duty cycle of the fixed frequency signal (222) when the analog dimming signal (252) is not present at the analog dimming signal input (212).

Abstract: A light emitting diode (LED) assembly and module including a substrate (48) having opposing first and second sides (50, 52); a capacitor (32) having first and second electrically-conductive plates (44, 46) respectively disposed proximate the first and second sides (50, 52) of the substrate (48); and an anti-parallel LED structure (34) electrically connected to the first electrically-conductive plate (44) and thermally coupled to the substrate (48).

Abstract: A light emitting diode (LED) assembly and module including a substrate (48) having opposing first and second sides (50, 52); a capacitor (32) having first and second electrically-conductive plates (44, 46) respectively disposed proximate the first and second sides (50, 52) of the substrate (48); and an anti-parallel LED structure (34) electrically connected to the first electrically-conductive plate (44) and thermally coupled to the substrate (48).

Abstract: A system and method for open loop bi-level ballast control providing multiple levels of illumination from a ballast-driven lamp. Power to a lamp is adjusted in response to a lamp control signal by adjusting the frequency driving the ballast powering the lamp. Line voltage feeds an AC/DC converter, which supplies DC voltage to a high frequency (HF) ballast. A frequency control circuit responds to a lamp control signal and supplies a ballast frequency signal to the HF ballast, which responds to the ballast frequency signal and adjusts the current supplied to the lamp accordingly. In one embodiment, the lamp control signal can be a bi-level signal providing bi-level illumination.

Abstract: A LED driver includes a high frequency inverter and an impedance circuit. The high frequency inverter operates to produce a high frequency voltage source whereby the impedance circuit directs a flow of alternating current through a LED array including one or more anti-parallel LED pairs, one or more anti-parallel LED strings, and/or one or more anti-parallel LED matrixes. A transistor can be employed to divert the flow of the alternating current from the LED array, or to vary the flow of the alternating current through LED array.

Abstract: An improved high frequency ballast is disclosed. The high frequency ballast establishes a lamp current for a gas discharge lamp during a starting operation of the gas discharge lamp wherein an operating ampere level of the lamp current facilitates a substantial achievement by the gas discharge lamp of a color specification associated with the gas discharge lamp. Thereafter, during a stable operation of the gas discharge lamp, the high frequency ballast applies a frequency modulation to an operating frequency of the lamp current and/or an amplitude modulation of the lamp current.

Abstract: A system and method for open loop bi-level ballast control providing multiple levels of illumination from a ballast-driven lamp. Power to a lamp is adjusted in response to a lamp control signal by adjusting the frequency driving the ballast powering the lamp. Line voltage feeds an AC/DC converter, which supplies DC voltage to a high frequency (HF) ballast. A frequency control circuit responds to a lamp control signal and supplies a ballast frequency signal to the HF ballast, which responds to the ballast frequency signal and adjusts the current supplied to the lamp accordingly. In one embodiment, the lamp control signal can be a bi-level signal providing bi-level illumination.

Abstract: An improved high frequency ballast is disclosed. The high frequency ballast establishes a lamp current for a gas discharge lamp during a starting operation of the gas discharge lamp wherein an operating ampere level of the lamp current facilitates a substantial achievement by the gas discharge lamp of a color specification associated with the gas discharge lamp. Thereafter, during a stable operation of the gas discharge lamp, the high frequency ballast applies a frequency modulation to an operating frequency of the lamp current and/or an amplitude modulation of the lamp current.

Abstract: A LED driver is disclosed. The LED driver includes a high frequency inverter and an impedance circuit. The high frequency inverter operates to produce a high frequency voltage source whereby the impedance circuit directs a flow of alternating current through a LED array including one or more anti-parallel LED pairs, one or more anti-parallel LED strings, and/or one or more anti-parallel LED matrixes. A transistor can be employed to divert the flow of the alternating current from the LED array, or to vary the flow of the alternating current through LED array.

Abstract: An electronic ballast for powering at least two rapid start, parallel connected fluorescent lamps. Associated with each lamp is a serially connected choke and capacitor combination. A train of pulses of alternating polarity having a fundamental frequency, which is generated by an inverter, is applied to each serially connected combination. Each combination is characterized by a resonant frequency which is other than an odd harmonic of and at least two times and preferably .sqroot. 5 times greater than the fundamental frequency. Reduction in filament heating, following lamp ignition, is provided through the addition of voltages applied to each filament which are substantially out of phase with each other.

Abstract: An electronic controller for fluorescent lamps includes a DC to AC converter which supplies high frequency current to the lamps and a preconditioner stage which includes a switched mode power supply connected to accept line power and produce a DC input for the DC to AC converter. The switched mode power supply and the DC to AC converter are synchronized to operate in a fixed phase relationship and/or at the same frequency.

Abstract: A controller operates in pre-ignition and ignition phases to obtain stable and reliable control of operation of a half-bridge DC-AC converter in a frequency range which is offset from a resonant frequency of an output circuit which includes a transformer and capacitors and which couples the converter to a fluorescent lamp load. The converter is supplied with a DC voltage from a switched-mode DC-DC supply of a pre-conditioner circuit which responds to a full-wave rectified AC voltage and which is supplied with pulse-width modulated gating pulses from the controller, preferably at a frequency which is the same as that of the converter. The controller monitors signals from the output circuit and pre-conditioner circuits and exercises control to reliable starting and highly efficient lamp operation and to obtain an in-phase proportional relationship of input voltage and current wave forms.

Abstract: An improved power supply for one or more electric discharge lamps includes a high frequency oscillator-inverter circuit coupled to the output of a full-wave rectifier circuit via a transformer primary winding (25). The rectifier circuit is energized from a low frequency source of AC voltage. The oscillator-inverter circuit supplies high frequency oscillations to the lamp via a frequency-dependent ballast coupling circuit. A regenerative power supply is coupled to the transformer primary winding by means of a secondary winding (62) of the transformer thereby to charge a capacitor (49) operative as a switchable auxiliary supply voltage for the oscillator-inverter circuit. Improved start-up operation is achieved by winding the transformer (25, 62) so as to provide a polarity inversion for the supply of electric energy to the regenerative power supply.

Abstract: A ballast control apparatus for an electric discharge lamp comprises a first series circuit including a first winding of an AC supply voltage transformer, a first winding of a ballast transformer, a lamp current sensing resistor and the lamp. A current sensing transformer has a first winding parallel to the resistor. A second winding of the supply voltage transformer, the ballast transformer and the current sensing transformer are connected in a second series circuit. A signal voltage proportional to lamp power is derived by adding together the voltages induced in the three series-connected second windings. A second signal voltage proportional to lamp voltage is derived across the series combination of the second windings of the ballast transformer and the supply voltage transformer. The voltage induced in the second winding of the current sensing transformer is proportional to lamp current.