If you’re testing a power supply or battery pack, an electronic load is a nice tool to have. By watching the voltage as you crank ... hang additional hardware or sensors on.

Drive the gate of the FET with an op-amp that maintains either constant current or constant voltage. Control everything with a DAC, and you have a programmable load controlled by an Arduino.

This post is in response to a reader who asked about detecting mains electricity using a microcontroller. The easiest and safest way to detect mains electricity using a microcontroller is with an ...

The hardware is consists of an Arduino microcontroller (here an Arduino Uno R3) and a pre-wired soil moisture sensor module ... for driving high-current/high voltage loads like water pump motors ...