Built and tested circuits that you can incorporate into your custom PCB projects.
Most of these circuits are also part of my listed projects.
Cheap, available and hand-solderable IC.
Embedded ATMEGA32U4, USB hub, matrix wired buttons, encodes and funky switches ++.
Voltage divider circuit to reduce the pin requirements of a 12-position switch to a single analog pin.
An example of chained WS2812 RGB LEDs
Collection of useful circuits, including 4-channel external 16-bit ADC and FE1.1s USB hub with port activity indicators.
A hall sensor circuit with an RC-filter.