Do I need a capacitor and resistor? Really want to get things rolling, but not sure if I can proceed without capacitor + resistor, came across this: https://learn.adafruit.com/adafruit-neopixel-uberguide/best-practices and they suggest to use them.
I’m trying to setup Adalight
Here’s what I have:
2x 60/1M - SK9822
5v 10a DC Power supply
Thanks guys! Also want to say, this is the best Google+ forum I’ve been to, you guys have helped me so much so far!
You don’t need a capacitor, but it might help on large power draws / brightness settings. Just start playing you will know later based on performance if you need the resistor or capacitor.
I would put them in, after all it is best practice.
If the resistor is to protect from a spike in voltage on the data line and the capacitor to help out on the current end during sudden draws. It seems like cheap insurance to include to help ensure proper function.
Best practice is to connect short, large gauge wires directly from the power supply to the LEDs. Often a capacitor is suggested because the power supply is weak or long, higher resistance wires are used. If only short duration pulses of higher current are needed, but big capacitor can help. But keeping the wires large and short, and run directly to the LEDs (not first to the controller) is by far the best way.
I’ve destroyed my first strip when I started. Later I found out that my power supply generates high voltage peaks when I turn it on or on heavy load fluctuations. A reasonable big capacitor solved this for me.
I also had problems with strange flickering on long data wires. The resistor solved this too.
If the power supply is switching (most low cost ones are), a cap will help make sure you don’t have weird power issues as well.
It’s best practice for a reason.
Can add that the lab I previously worked with (of software engineers!) blew out the first pixel of a good number of strips before they started using big capacitors on the power lines.
NUM_LEDS=59 and NUM_LEDS=143 were very much in vogue that summer…
Alright, thanks guys! I couldn’t wait and finished soldering everything and got FastLED working! I’ll go ahead and order the capacitor, is there a place you guys recommend to buy one?
Do I get a 1000uF 6.3v one like the post? I’m running ~111 SK9822 LEDs with a 5v 10a power supply and sending data via a pro micro.
Also when I get it, do I attach it to the + and - of the barrel jack like the adafruit post has?
missing/deleted image from Google+
Mouser is a reliable source in my opinion; get a 1000uF (or bigger) that can handle the forward voltage needed by your LEDs. http://Mouser.com has good candidates in the $0.60 range for quantity one, and almost half that for quantity 10. I hook mine up exactly per the Adafruit guide.
Alright thanks! I’m still a bit lost on the voltage rating though, since I have a 5v 10a PSU running 111 strips, that’d be like 6.6 amps right? What do you suggest? Should I just get the 6.3v or go higher?
For the 1000uF cap, get 16V as it’s a good idea to have something with a voltage rating of 2-3 times whatever voltage is being used, and it will give you a larger safety margin.
Here’s a post with some good info.