Single 5mm Accent Neopixel not Lighting Up while Lighted Switches Work

Proffieboards
1

Hello, I just finished another saber build, and everything is working, minus a 5mm accent LED used for the crystal chamber (5.4mm Micro Pixel Accent PCB). For context, this install includes two lighted switch pcbs (Pixel Switch PCB), in addition to the main blade (Pixel Connector PCB) and crystal chamber. Each have their own unique data line and FETs.

I very recently built another saber with the same wiring (bladePin2, bladePowerPin1, tied into Batt+) using a slightly larger 8mm version of the single neopixel pcb. That saber works fully as expected, including the crystal chamber. Note, that the other install didn’t have the lighted switch pcbs.

I checked the blade configs for the crystal chamber blade, and they’re identical between the two (config for this install attached). I then checked continuity between FET 1 pad on the board and negative on the accent pixel, Batt+ on the board and positive on the accent pixel, and Data2 on the board and Din on the accent pixel. All returned continuity.

I then started looking at the Proffie board, to make sure the FET and data pad I was using were working, according to ProffieOS Documentation: How to test a FET and ProffieOS Documentation: How to test if data pins are working.. The FET returned 3+ VDC, so it seems it’s fine. The data pad readings flucutate wildly across all 4 data pads, but I saw 1+ VAC at points during the readings on Data2 connected to the accent pixel for the crystal chamber.

Having exhausted what I could think of by checking continuity, board components/pads, and config, I’m not sure what else to check. Does anyone have any advice?

MW3-BMF.h (50.0 KB)

2

Have you tried using a different pixel?
It may be that your accent pixel is simply not working.
The links you posted don’t work for me, so I can’t check what kind of pixel(s) you have, but really anything that speaks the WS2811 protocol can be used to test if the board is producing the right signals or not.

3

I have not. That was where my mind was headed next. I don’t have another one on hand. I could add one into my next parts order. Is there a good way to test the accent pixel I’ve got in there to see if it’s the problem? Note: the accent pixel is the 5 mm pcb from Shadowfoil Props.

4

You don’t have any leftover led strips ? Even 1 pixel would do. Just make sure you have a resistor too.

5

I do have some scrap bits of the WS2812X strips I’ve used to make blades. The only resistors I have on hand are some of those 0603 330 Ohm SMD resistors. From what I understand, the resistor in the data line is intended to prevent unwanted current from cooking the pixels via the data line. How important is that for short term tests like this?

6

Data line won’t “cook” the pixel at all. It just might get scrambled on it’s way to the pixel.
Low probability at short range, plus data 1 pad already has a built in resistor, so…

7

Ok. I can hook up one of my scrap strips the way the pixel is hooked up and report back.