CrossRoads:
The LED is the combined driver+LED module WS2812B, there is a cap next to the part.If you're going to turn on more than a few (and 36 is well more than a few), I would strongly suggest a separate power supply for the strip.
So just to be sure I’ve got this;
I don’t need decoupling capacitors as the strip has them built in.
I do need the resistor (470 ohm?) on the data line.
I do need a (1000 microfarad?) capacitor across +5v and GND.
Ideally I should use a separate power supply for the LEDs.
I can’t do a lot about the last one. The project requires a simple, single socket power supply. Even if I provided two, very few users are going to plug two in; I know there are things like lipo packs that could be used, but the project is limited in both space and cost, so would not accommodate them.
Given that, could you clarify what the actual risk is of not doing so and if there is any other way to mitigate it? As I said I’ve run my demo versions of these for hours at a time over the last six months with neither capacitor, resistor or any other protection and not lost any LEDs, controllers or had any other adverse situations. I realise I may just have “got away with it” and hence if the cost is only a few pence (cents) I can happily add, but if it’s a few £ ($) it becomes a problem.
Thanks all!