Constant Current Bright LEDs
For most of my LED applications a very special circuit was designed to run the LEDs at a “constant current”. This provides a constant amount of power to the LEDs and also provides a constant amount of light for a longer period of time. This circuit also allows the LEDs to run on almost any normal voltage above 4 volts. This means you can use multiple sources of power for the same light, a few AAA batteries, or even a car battery .
   Constant Current Bright LEDs
More detail on Constant Current Bright LEDs website
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