Abstract: An analog AC driven fully dimmable circuit that reduces the gap between peak current and a minimum current to improve dimming properties and provide additional functionality to a lighting device. The circuit provides ancillary circuitry that bypasses an analog step driving section of the circuit without the use of an ancillary transistor. The ancillary circuitry bypasses the analog step driving section of the circuit and has a capacitor to continuously Provide current to the first series interconnection such that the first series interconnection continuously emits light during operation of the circuit.
Type:
Application
Filed:
August 18, 2017
Publication date:
April 5, 2018
Applicant:
Once, Inc.
Inventors:
Zdenko Grajcar, David Natarelli, Hoa Huynh
Abstract: Apparatus and associated methods reduce harmonic distortion of a excitation current by diverting the excitation current substantially away from a number of LEDs arranged in a series circuit until the current or its associated periodic excitation voltage reaches a predetermined threshold level, and ceasing the current diversion while the excitation current or voltage is substantially above the predetermined threshold level. In an illustrative embodiment, a rectifier may receive an AC (e.g., sinusoidal) voltage and deliver unidirectional current to a string of series-connected LEDs. An effective turn-on threshold voltage of the diode string may be reduced by diverting current around at least one of the diodes in the string while the AC voltage is below a predetermined level. In various examples, selective current diversion within the LED string may extend the input current conduction angle and thereby substantially reduce harmonic distortion for AC LED lighting systems.
Abstract: A method and lighting system for promoting survival of larvae from a plurality of eggs within a containment unit. The lighting system includes at least one lighting device emitting light energy in a pre-determined narrow range of wavelengths and a pre-determined lighting intensity that promotes the survival of the larvae within the containment unit.
Abstract: A circuit having a series interconnection of a light-emitting diode (LED) group, a first transistor, a second transistor and a first resistor. The series interconnection has a cathode coupled to a drain terminal of the first transistor and a source terminal of the first transistor is coupled to a first terminal of the first resistor wherein voltage across the first resistor to provide a biasing voltage for the first transistor. A source terminal of the second transistor is coupled to a first terminal of the first resistor wherein voltage across the second resistor provides a biasing voltage for the second transistor and ancillary circuitry bypasses the series interconnection. The ancillary circuitry has a capacitor to provide current to the series interconnection to increase the amount of light emitted during an electrical excitation cycle.