Plan your keyboard

The point of this step is for you to have a vision of what you want to make, so you can easily execute on your idea.

#Know your parts

Before you start placing components in KiCAD, it helps to know what everything actually is and how it fits together physically.

#Switches

Switches are the mechanical components under each key, the part you actually press. When you press a key, the switch closes an electrical circuit that the Pico detects.

There are three main types:

• Linear: smooth and consistent from top to bottom, no bump or click. Popular for gaming.
• Tactile: a subtle bump partway through the press gives you feedback that the key registered. Quiet but noticeable.
• Clicky: has both a tactile bump and an audible click. Satisfying, but loud.

This project uses MX-style switches, which is the most common standard. Almost all aftermarket switches, keycaps, and plates are compatible with it.

#Keycaps

Keycaps are the plastic caps that sit on top of each switch, the part your fingers touch. They pull off and snap back on, so they're easy to swap.

Keycaps come in many profiles (the shape and height), but for this project DSA keycaps are a good choice because every key is the same height, which means one set fits any layout without worrying about rows.

#Stabilizers

Wider keys (2u and above, like spacebar, backspace, left shift, and enter) would wobble if held only by their switch. Stabilizers are mechanical brackets that clip onto the PCB and keep both ends of the key moving evenly.

You only need stabilizers for keys that are 2u or wider. Anything smaller uses just the switch.

#The Raspberry Pi Pico

The Pico is the microcontroller, the "brain" of the keyboard. It reads the switch matrix, figures out which key was pressed, and sends that keypress to your computer over USB.

The Pico solders directly onto your PCB through-hole. Its USB-C port will hang off the edge of the board slightly so you can plug a cable in.

It has 29 GPIO pins, which is why we use a matrix. A 60% keyboard has far more keys than available pins.

#Diodes (1N4148)

Each switch has a 1N4148 diode wired in series with it. Diodes only let current flow one way, which prevents "ghosting", a problem where pressing multiple keys at once confuses the matrix and registers phantom keypresses.

These are through-hole components (legs go through the PCB) and are straightforward to solder.

#Optional add-ons

If you want to go further, these parts can be added to your PCB:

These are all optional. You can keep it simple and just build a clean typing keyboard.