Sometimes, rather than going the commercialistic route, it can be nice to make a gift for that personal touch. [Mahesh Venkitachalam] had been down this very road before, often stumbling over that common hurdle of getting in too deep and missing the deadline of the occasion entirely. Not eager to repeat the mistake, help was enlisted early, and the iCE bling earrings were born.
The earrings were a gift for [Mahesh]’s wife, and were made in collaboration with friends who helped out with the design. The earrings use a Lattice iCE40UP5k FPGA to control an 8×8 grid of SMD LEDs. This is all achieved without the use of shift registers, with the LEDs all being driven directly from GPIO pins. This led to several challenges, such as routing all the connections and delivering enough current to the LEDs. The final PCB is a 4-layer design, which made it much easier to get all the lines routed effectively. A buffer is used to avoid damaging the FPGA by running too many LEDs at once.
It’s a tidy build, which makes smart choices about component placement and PCB design to produce an attractive end result. LEDs naturally lend themselves to jewelry applications, and we’ve seen some great designs over the years. Video after the break.
We love seeing a thing get used effectively for other than its intended purpose, and this DIY LED Earrings project is a great example. [IdunnGoddess] liked the idea of making light-up LED earrings powered by a small coin cell, but an enclosure and power connection for the battery were sticking points. The solution? A googly eye after a few minor modifications turned out to be perfect.
A googly eye resembles a thin, flat, hollow plastic bulb. Choose one that’s just a bit bigger than the coin cell, and cut a slot in one end and a small hole in the other. The LED leads go into the hole, and the coin cell slides into the slot. The result? A lightweight battery holder for an attached LED, and as a bonus the hacked googly eye is a clean and super smooth surface that can easily be painted or decorated to make it part of the design. The video embedded below demonstrates the process and showcases a few sample designs.
Settle back and watch [mitxela]’s miniature wizardry in the video below, but be forewarned: it runs 36 minutes. Most of the video is necessarily shot through a microscope where giant fingers come perilously close to soldering iron and razor blade.
The heart of the project is an ATtiny9, a six-legged flea of a chip. The flexible PCB is fabricated from Pyralux, which is essentially copper-clad Kapton tape. [Mitxela] etched the board after removing spray-paint resist with a laser engraver – an interesting process in its own right.
After some ridiculously tedious soldering, the whole circuit wraps around a CR927 battery and goes into a custom aluminum and polypropylene case, which required some delicate turning. Hung from off-the-shelf ear hooks, the 12 multiplexed LEDs flash fetchingly and are sure to attract attention, especially of those who know Morse.
The HackPhx Winter 2014 hackathon was held at Heatsync Labs hackerspace in Mesa, Arizona, USA. The advertised theme was “Arduino Wearables”. Participating attendees were randomly placed on teams evenly distributed by their disclosed skills across all teams. There were 10 teams with 4 to 5 members per team competing for two winning spots.
Top prize was the Judges’ prizes for the best completed and documented Xadow wearable team project. The second prize was the Jury’s prize given to the team project that the other teams liked the most regardless of event criteria.
Read more about the winning teams and watch their presentations after the break.