Smart Puck Synaptics Coral Board

Coral Voice-Note Puck

Tap the top or say a wake word, speak a thought, and the puck transcribes it on the Coral NPU. Nothing goes to the cloud. Notes can sync to your notes app (I’m planning to send mine to Obsidian). It’s a small, private, always-ready voice notepad for your desk.

Modular by design: PuckLock
Every module joins with the same 3-lug twist-lock: a 35° turn that clicks into a detent. That means you can stack modules in any order and design your own. An 18 mm channel runs through the center of every module so cables can pass between them.

Modules included

• Top cap: speaker grille for a 40 mm speaker, mic pinhole, and a recessed tap/mute button

• Light ring: print it in clear or natural PETG. An internal LED-strip channel glows to show listening, thinking or done.

• Core: holds the board on M3 standoffs matched to its 65 × 48 mm hole pattern. A recessed rear port bay gives access to USB-A, USB-C, the USER/RESET buttons (pin-poke holes) and a status-LED window.

• Mic boot: a small acoustic duct that clamps under one board screw. It carries sound from the onboard mic straight up to the cap pinhole, which lines up when the cap is locked.

• Battery module: a 1S2P 18650 cradle for the board’s BATTERY connector. There’s also an alternate pocket for a slim USB power bank.

• Foot base: rubber-foot recesses and a USB-C cable exit

Built from the real board
Mounting holes, port positions and component heights come from the official CoralBoard SL STEP model and were checked against board photos. A reference model of the board is included for fit checks.

Suggested hardware

• Synaptics Coral Board (SL)

• 40 mm 4 Ω speaker + I2S amplifier (e.g., MAX98357A) on the I2S2 header, or a mikroBUS speaker add-on

• WS2812 LED strip (about 60 LEDs/m) for the light ring

• 4× M3 × 6 screws or heat-set inserts

• Foam rings for the mic seal (5 mm and 8 mm)

• Optional: 2× 18650 cells with protection (check the board docs for supported battery chemistry and voltage)

• 4× 12 mm rubber feet

Print settings

• PLA or PETG, 0.2 mm layers, 3 walls, 15–20% infill

• Light ring in clear or natural PETG

• Print the top cap upside down (the STL is already oriented)

• Supports are needed only under the rear port bay roof on the core

Honest note
I designed this before getting my hands on a board, so everything is built from the official STEP model and photos. If I win one, I’ll print it, test the fit, and post an update with real photos and any tweaks to the port cutouts and mic seal.

Files
STLs for all parts,and a Blender scene with the renders and an explode animation.