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# of LEDs off of a Keywhiz Eco
NoBonus:
I want to run one or more LEDs off of the 5v output on my KeyWhiz Eco, however, I am not sure how many the 5v output could push in parallel without causing any problems. Any ideas? I am leaning towards using 3.6v white or blue LEDs(with appropriate resistors), but how many will I need to successfully light my blue translucent trackball and not burn anything up?
Thanks
Buddabing:
Here's an informative page.
I have read that you should not pull more than 100 mA through a keyboard port. If each LED draws 15-20 mA, three or four LEDs should be safe enough.
You should ask Randy.
NoBonus:
I see a lot of talk about the negatives of using LEDs in parallel withonly one resistor, but recommendations about parallel with one resistor per LED. Unfortunaly, I see no info on hooking up LEDs in parallel with individual resistors. Do you know where I can find this info?
NoBonus:
I also noticed that at lsdiodes, I can get a 5mm Blue THC3 11000mcd LED that uses 80 to 100 mA or I can get 3 or 4 5mm Blue - 5900mcd LEDs that use 20 to 30 mA... which is the better pick? Am I better off with a single, brighter light or a few dimmer lights to light a translucent blue trackball?
NoBonus:
Also, do I run the LEDs at "TYP" or "MAX"? Will "MAX" fry them?