Not exactly schematics, but [Duckman] has some Arduino pinout diagrams he made using ASCII-art. These could be useful when pasted into source code as comments, documenting the pinouts for your ...

Sometimes, you'll also encounter Arduino tutorials in the wild that include links to a Wokwi circuit as creators and developers typically create one to show the project's schematic diagram. Other ...

Looking at the schematic, it looks like using the DS18B20 temperature sensor (and the infrared receiver module) requires a bit of research. As indicated in the top silkscreen layout, the flat (labeled ...

The resistor values (R1&R2) in the circuit diagram provide some over-voltage protection then measuring low voltages. Keep it in mind that any input voltage higher than about 55V could fry the Arduino.

There’s a few open source options out there for creating electrical schematics. KiCad and Fritzing are two that will take you from schematic capture to PCB layout. However, there’s been… ...