The Cree-board

Description

The cree-board is a wireless nine key keyboard/macropad using Cree CXA1304 LEDs as the buttons. Just like your RGB gamer keyboard, each key lights up when pressed but not with a weak 3v RGB led. Each key press on the cree-board lights up your finger with a super bright glow of 93 CRI 3000k white light.
Why use COB LEDs as keyboard keys? They look cool and are the perfect shape and size for keyboard keys. The bright white and translucent orange look really nice together, like little square sunny-side up eggs. Also the rubbery orange center feels really nice to press (even though the datasheet says not to do this).
It communicates wirelessly using an ESP32-C3 to a another ESP32 connected to the computer over the ESP-NOW protocol but it still needs plugged in to the wall with a 9v power supply. The LED buttons are glued to a 3d printed shell. The thin plastic under the LEDs act as a spring over standard tact switches. The board also contains a USB type B connector for programming.

Details

Accessing hackaday.com with one bright key press.

This definitely isn't a super practical project but I thought of the play on words with "cree" and needed to make it a reality. Someday I'd like to try and build some cherry mx keycaps with these COB LEDs embedded in them so they can fit on standard mx keyboard switches. This project was a first test of the concept. It might not be feasible to build a large keyboard like this because of the cost of these LEDs. Plus the brightness might be distracting if you were actively typing on it. I’m limiting the current to a fraction of the max current that these LEDs can handle. I wanted to avoid melting the PLA case and burning my eyes and fingertips. I chose to use 38 awg enameled copper wire to connect the LEDs to the pcb. This is mainly an aesthetic choice to keep the front of the keypad looking clean.

I'm using a usb dongle I made for previous project as the receiver for the cree-board. The dongle is just a ESP32-S2 module, usb connector, and power regulator. The ESP32-S2 has USB hid support which works perfect for this project. I've also include the files for the dongle in this project page.

Files

base.STL

case bottom section

Standard Tesselated Geometry - 326.64 kB - 07/04/2022 at 00:59

Download

top2_v2.STL

case top section

Standard Tesselated Geometry - 160.14 kB - 07/04/2022 at 00:59

Download

ESP32-S2_v4_dongle.sch

receiver dongle eagle schematic file

sch - 153.03 kB - 07/02/2022 at 21:49

Download

ESP32-S2_v4_dongle.brd

receiver dongle eagle board file

brd - 65.97 kB - 07/02/2022 at 21:49

Download

creeboard_receiver_demo_had.ino

demo arduino sketch for receiver esp32-s2 connected to computer

ino - 2.76 kB - 07/02/2022 at 21:47

Download

Components

9 × Cree CXA1304 LED COB 3000K WHITE

9 × DMN2056U-7 N-Channel MOSFET

1 × Barrel Jack 2.1X5.5MM

1 × ESP32-C3 WROOM Module

1 × USB B Connector

Discussions

Florian wrote 07/04/2022 at 23:16

Using COB as a light/keypad combo is something I would never have thought of. Interesting concept. But as a former lighting fixture engineer who worked with COB, when I saw that photo of your finger directly pressing the light emitting surface I heard Michael Scott screaming "No God no" in my head. XD

Are you sure? yes | no

Matt Deeds wrote 07/06/2022 at 20:59

lol, yeah it's definitely not a manufacturer approved use case

Are you sure? yes | no

The Cree-board

Description

Details