[sdiy] LEDs and noise

[Oren Leavitt]

On 5/7/2015 6:32 PM, David Moylan wrote:
> If you're dealing with a lot of "blinkenlights" what's the best way to
> handle them?  Is it better to power them between the + and - rails or
> from one rail to ground?  Is it worth using a "dirty ground" scheme, or
> is the noise induced on the supply rails itself?
>
> Thanks.
>
> Dave


I personally like to put LEDs, each with a driver transistor, on a 
separate board with its own + rail and dirty ground.
If a separate + rail is not handy, you can decouple the LED + rail from 
your main + rail with a low R (say 10 ohms) and an electrolytic cap (47 
uF). R between main + rail LED + rail. Cap from LED + rail to ground.

- Oren