Is this why you need a capicitor?

[Squimboos]

So I recently had time to get to building these things. Anyway, first go around a capicitor wasn't needed on my neopixel blade. Now something odd is happening. Using a tcss neopixel adapter, 24 awg on power lines, and 28 awg on data (470 ohm resistor), the board boots fine and the blade ignites. But now, after a few seconds and with color changing and lock up effects, some parts of the strips will act goofy. The strips will stop lighting up half way up on one side. The colors will lock or even stay on after powering down.

I've rewired the connector on both sides and I thought I fixed it until I charged up my battery completely. Turns out I only get functional strips when the battery is low. From reading a troubleshooting guide I've found that the power lines voltage can only be 1.43 times the data line voltage or esle the strips go wonky. So I'm imagining that with the battery fully charged the power spikes are causing the power voltage to be over 1.43x the data.

Am I on the right track here? Is this why a capicitor is needed to smooth out the power to the strips?

Thanks for reading. I'd love to know if this is the issue.

[Meatsweats]

What battery are you using?

[Squimboos]

The tcss protected 10 amp 3200 mah

[Meatsweats]

I’ve build 4 neopixel blades and I haven’t used a capacitor yet. The only time I’ve had the leds act like that is when I messed up the wiring or the strip itself was bad. Maybe someone else can chime in...

[Squimboos]

Yea it's possible it's still a wiring issue. I'll probably do a little rewiring here in a bit.

[hutch009]

Can somebody explain why a capacitor would be needed on the neopixels in general ?

@Squimboos can you provide a link to the Neopixel troubleshooting guide you mentioned in your first post?

[RavenXp]

Can somebody explain why a capacitor would be needed on the neopixels in general ?

@Squimboos can you provide a link to the Neopixel troubleshooting guide you mentioned in your first post?

Direct quote from the PRIZM 5.1 manual;
"While a proper battery will be able to supply the strip(s) current transient upon boot,
another great and common practice with the strips is to add a 330 to 470µF
electrolytic capacitor next to the strip (it can be easily hidden and stored within the
blade tube)."

Going by that, I think it's to buffer the load from the battery while the strips light up.

[jbkuma]

Going by that, I think it's to buffer the load from the battery while the strips light up.

This is correct. Here's another source for information on general "pixel" usage https://learn.adafruit.com/adafruit-...ic-connections

The issues described in the OP would more likely be a bad joint or other problem with the signal line. The pixels are pretty tolerant and will tend to correct the signal if it's close enough. Try using a 220ohm resistor.

[Squimboos]

Is there any reason why my strips would only work with a low battery charge?

[hutch009]

To everyone that replied to my question, thank you for the information. I want to try making my own Ledstrip saber down the road but right now I am still in the learning stage. I am not completely comfortable with the concept of what a capacitor is or how it actually works so it is back to the electronics books to read up. Any recommendations?
@Squimboos have you found a solution to your led strip problem?