LED driving system and method for variable voltage input

摘要

A plurality of light emitting diodes (LEDs) is driven based on the voltage and current requirements of the LEDs at any given time. The driving of the LEDs is adapted to the input voltage provided. A series of switches (e.g. MOSFETS) is used to selectively illuminate the LEDs according to the input voltage and current, with more LEDs being lit as the input voltage or current increases. In one configuration, the switches are driven to provide a light dimming function. The LEDs can be controlled remotely using, e.g. an X10 communication protocol. A direct current implementation is also provided. In an alternate embodiment, the LEDs are used in photo diode mode for communication with a remote controller or other light bulbs.

主权项

1. A reconfigurable LED system comprising:
a plurality of LEDs electrically connected in series, each of the LEDs having an electrical connection with a first polarity and an electrical connection with a second polarity; a power source with a first polarity and a second polarity; a respective switch connected between said second polarity of said power source and said second polarity of each of said LEDs; and a controller for continuously monitoring at least one of voltage and current supplied to said plurality of LEDs and for selectively controlling switching of said respective switches in response to the at least one of voltage and current supplied; an inductor between said first polarity of said power source and said first polarity of a first of the series connected LEDs; wherein said reconfigurable LED system accommodates voltage variations in said power source by modulating at least one of the switches so as to maintain a desired average current through the plurality of LEDs connected to the power source.