Exceptionally Good LED Power Tutorial
A seriously talented person wrote this article and it's for beginners! http://led.linear1.org/why-do-i-need-a-resistor-with-an-led/
Forum Discussion
Most LED assemblies have the needed regulators in them, either a simple resistor or a current regulator (Which may be nothing more than a 3 terminal voltage regulator with a resistor) ...
His info is for those who BUILD the assemblies themselves.. IE: ME.
And it is a good start. You also need to know Mr. Ohm's Law.. you know, Resistance is futile.. Oops. that was Davros' Law. Ohm's is I=E/R so R = E/I you also need to know the forward bias voltage drop for the LED. By my calcs a JUMBO High Brightness LED from Radio shack needs about 450 Ohms for a RV. The standard size LED in my light up grab bar cane with a 150 Ohm. and promptly burned out from too much current.. So did the one I repalced it with, Then I metered the resistor and upgraded it and have not replaced one since. NOTE teh Jumbo High Brightenss led sucks a bit more current than the standard ones.
His info is for those who BUILD the assemblies themselves.. IE: ME.
And it is a good start. You also need to know Mr. Ohm's Law.. you know, Resistance is futile.. Oops. that was Davros' Law. Ohm's is I=E/R so R = E/I you also need to know the forward bias voltage drop for the LED. By my calcs a JUMBO High Brightness LED from Radio shack needs about 450 Ohms for a RV. The standard size LED in my light up grab bar cane with a 150 Ohm. and promptly burned out from too much current.. So did the one I repalced it with, Then I metered the resistor and upgraded it and have not replaced one since. NOTE teh Jumbo High Brightenss led sucks a bit more current than the standard ones.
