View single post by Si.
 Posted: Sun Jun 30th, 2019 10:05 am
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Si.



Joined: Thu Feb 23rd, 2012
Location: London
Posts: 5236
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How to recognise the standard 'colour band codes' on most resistors.  :brill:

And calculate what value of resistor is needed for your LED types.  L:








Resistor value in Ohms = VS 'Supply-Voltage' ... MINUS - VF 'Forward LED Voltage' ...

... DIVIDED by the maximum, or desired, LED current in Amps, ie. say 20 mA = 0.020 Amps.

The answer is the 'current limiting resistor' value in Ohms, which can be a 'nearest value'.





An example of 'chaining' LEDs using different resistor values & different Voltages.






:!: :!: :!: :!: :!:



Si.




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