Hi guys, great advice!
The 1000uF cap at the first WS2812B was a tip from adafruit. Maybe it is only necessary when want to use many leds? At the moment I am playing with only 10 leds. But in the future I will use (many) more. Therefore I want to do it right the first time - even if I can power those 10 directly form my core.
I use small pcb’s with a WS2812B, 100uF cap and a resistor onboard.
Conclusion: The 7805 is inefficient. Big voltage drop and a lot of heat. Shame that I have like 20 of them… So I will only use when I only need a limited amount of current.
So it’s great to know there is an better alternative for the 7805.
- I never heard about a “DC-DC switching converter”. It looks like those things are “plug and play” - so perfect!
- A “switching power supply” is also simple to use. But a bit overkill for the few leds I want to power. I will keep it in mind when I want to power a lot of them! @digixx; also thanks for the tip to power them at least every 5m
I’ve never heard of a Level shifter @BDub. So can you tell me if I got it right?
They are like a bridge. It converts a 3.3v signal (which comes from my spark core) to a 5v signal (to de DataIN of the LEDS).
Like a transistor? But why can’t i use a NPN transistor instead?
Thanks for the (simple) picture, that will help me a lot(!) when I want to use them!
Also an idea: is it smart to put a 1N4001 diode before the vin pin to lower the voltage? (So the LDO on the spark core hasn’t have to work so hard?) The idea came from: https://learn.adafruit.com/battery-power-for-led-pixels-and-strips/diode