The Cree-Board Combines LEDs with a Keyboard to Create a Unique Macropad
This nine-key macropad features Cree LEDs that function as keys when pressed, illuminating the underside of the user’s finger.
Macropads, 9-key or 10-key peripherals are great to have on hand for any number of applications, including video and photo editing, music mixing, gaming and more. Most pads feature a series of keys outfitted with either mechanical or rubber dome switches, but occasionally a platform comes along that separates itself from the others. That’s the case with Matt Deeds' unique Cree-Board, which replaces conventional switches with super bright Cree LEDs that illuminate the underside of the fingertips when pressed (well, sort of*).
“Why use COB LEDs as keyboard keys? They look cool and are the perfect shape and size for keyboard keys,” Deeds states in his project blog. “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).”
The board is based on an ESP32-C3 microcontroller for wireless communication with a PC equipped with an additional ESP32 board via the ESP-NOW protocol.
The LED buttons are glued to a 3D-printed shell with thin plastic that acts as a springboard for conventional tactile switches* positioned below. When the LED is depressed, it activates the spring switch below to complete the circuit and illuminate the LED. Think of it as similar to a mechanical keyboard with LEDs on the PCB; in this case, each LED is affixed to the switch itself.
Because the Cree LEDs are insanely bright (CRI 3000k), Deeds has them at half power; otherwise he runs the risk of melting the macropad’s 3D-printed case. It should also be noted that he’s using a dongle he made from a previous project as the receiver for the Cree board, which has a USB connector and power regulator.
Deeds has provided a complete walkthrough of his build here.
