Quote:
Originally Posted by Avulon
To properly control brightness an LED driver is used with variable PWM.
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Yep thanks, I have a variable PWM but it's physically big for the job.
Quote:
Originally Posted by Phil-T4
You would need to know the forward voltage of the LED i.e. the voltage that it turns on and also the current rating in mA to drive it, different colour LED's has different forward voltages and current ratings.
Try this for starters... http://led.linear1.org/1led.wiz |
Great link, thanks Phil. The LED is described as 0.1W operating between 6/12V which taken at face value, means an 8mA rating at 12V. If that's correct, then guessing 9V as the forward voltage on the linear1 calculator, produces a 390kΩ resistor. Am I on the right lines? Maybe I should just (re)consider a small PWM.
Dougie.