CURRENT ROUTING TO MULTIPLE LED CIRCUITS
An illumination module includes a plurality of Light Emitting Diodes (LEDs) located in different zones to preferentially illuminate different color converting surfaces. The flux emitted from LEDs located in different zones may be independently controlled by selectively routing current from a single current source to different strings of LEDs in the different zones. In this manner, changes in the CCT of light emitted from LED based illumination module may be achieved.
1 . An LED based illumination device, comprising:
a first LED string comprising a first plurality of LEDs coupled in series, wherein a current supplied to the first LED string causes a light emission from the LED based illumination device with a first Correlated Color Temperature (CCT);
a second LED string comprising a second plurality of LEDs coupled in series, wherein the current supplied to the second LED string causes a light emission from the LED based illumination device with a second CCT; and
a current router comprising,
a first node coupled to a current source, the current router operable to receive a current signal on the first node,
a second node coupled to the first LED string,
a third node coupled to the second LED string, the current router operable to selectively route a first portion of the current signal to the first LED string over the second node and a second portion of the current signal to the second LED string over the third node based on a property of the current signal.