I Reverse Engineered a BLDC Motor (No Datasheet!)

Reverse Engineering a Brushless DC Fan Motor (No Datasheet!) Everyone uses brushless DC fans. Very few people actually stop and ask how they work. In this video I tear one apart and reverse engineer it from scratch. No application notes. No magic. Just an oscilloscope, comparator circuits, a pile of test equipment, and a lot of curiosity. We dig into: • How the stator is wound • Ring magnet pole arrangement (NNSS vs NSNS) • Back-EMF generation and what it actually looks like on the scope • Building a comparator circuit to detect the magnetic field and create clean switching signals • Measuring timing, pulse width and electrical angle • How these motors can be driven with surprisingly simple electronics once you understand what's happening Along the way I also blow up a few assumptions (and maybe a few components). The goal isn't just to make the fan spin. It's to actually understand why it spins. If you've ever wanted to design your own BLDC controller instead of treating it like a black box, this series is for you. Equipment used • Oscilloscope • Signal generator • LM393 comparator experiments • Custom test fixtures • Bench power supplies • Lots of coffee If you enjoy real engineering—not just Arduino tutorials—consider subscribing. I'm documenting everything I learn while designing RF hardware, power electronics, embedded systems, and test equipment. No gatekeeping. Just building cool stuff. #electronics #engineering #bldc #brushlessmotor #motorcontrol #backemf #oscilloscope #embedded #reverseengineering #hardware #electricalengineering #electronicswithjoe