The build
This project is a continuation of my previous Wearable Neopixel Stars project.
I created the LED starts about two years ago, and since then my flex PCB design and DFM knowledge has improved so i thought i'd make another version.
The Star is the old version and the hexagon is version 2 of my wearable neopixels.
PCB Layout:
The following picture show the pcb layout:
Top Layout:
Bottom Layer:
3D Layout:
FPC Ordering and Assembly:
I ordered a 2L FPC with a PI stiffener and asked PCBWay to design it in a 2x2 array.
The PCBWay staff was super helpful. They confirmed my flex stackup and material selection, and they even gave me some tips on the adhesive PA material. They also sent me the 2x2 array Gerbers to review before the design was approved.
After a few short weeks i received a stack of 100 FPC hexagons and a solder stencil and it was time to get to work
Stencil:
I checked the FPCs for any defects during IQC inspections, and everything looked good. The coverlay tolerance and drill vias were within spec.
PCB Top:
Each hexagon has 30 WS2812B-2020 leds with data in and data out testpoints so that the the hexagons can be connected in series and daisy chained.
PCB Bottom PI & PSA:
One of the issues i had with the previous LED stars is that the traces would crack very easily so this time i opted to add a PI stiffiner to strength the flexes while still allowing some flex.
I also added a high temperature double sided tape so that the hexagons could be peeled and sticked onto projects.
I was pretty impressed with the PCBWay Flexible PCB quality, both the adhesive and the FPCs heated up really well during my manual SMT process (hotplate) and have held up well against manual reworks.
Assembly:
I used my previous WLED-Pixie project to drive these leds, but this time i printed a new enclosure with loops for straps to mount.
The enclosure features an adhesive wifi antenna on the top and a battery under the PCB
Check out my previous WLED-Pixie project to see more details.
Feild Testing:
I envisioned this to be a project that could be worn on skin or glued to clothing and creates a wearable system that can be networked to sync the led patterns with your friends.
One version i created was a wearable with the WLED (WIFI controller & Battery) worn as a choker and the led hexagons worn as nipple pasties.
