USB Soldering Iron: #Teardown and Reverse-Engineer Schematic

USB soldering pens have always been something of an anomaly to me. I have two and they’re not only impressive, they’re sometimes more reliable (for their portability) than my Weller units. In this teardown video by bigclive he not only examines the PCB powering his USB pen, but he reverse-engineers the schematic and explains it – and yes, (spoiler!) that’s a 555 at the heart of this circuit!


When I bought this I was very sceptical that anything powered from a USB port could actually produce enough heat to solder. But here it is, tested and reverse engineered for your viewing pleasure.

Join 4,000+ makers on Adafruit’s Discord channels and be part of the community! http://adafru.it/discord

Learn “How Computers Work” with Bill Gates, Ladyada and more – From Code.org !

CircuitPython in 2018 – Python on Microcontrollers is here!

Have an amazing project to share? Join the SHOW-AND-TELL every Wednesday night at 7:30pm ET on Google+ Hangouts.

Join us every Wednesday night at 8pm ET for Ask an Engineer!

Follow Adafruit on Instagram for top secret new products, behinds the scenes and more https://www.instagram.com/adafruit/

Maker Business — Prototyping PCBs with Particle, a guide from a pro in the field #makerbusiness

Wearables — From mat to hat

Electronics — Even lower power!

Biohacking — Nectome’s Brain Preservation and Backup Service Plan

Python for Microcontrollers — Scott ([email protected]) on the Amp Hour podcast!

Get the only spam-free daily newsletter about wearables, running a "maker business", electronic tips and more! Subscribe at AdafruitDaily.com !


  1. I went ahead and ordered one. Should be perfect for when I’m out with friends at our hobby spaces. That leaves me with two questions is that regular solder you are using or a lower melting one that might of come with the usb soldering iron. And the RGB Controller is it for a bigger project 🙂

  2. I don’t have this exact iron but I have had to use a portable iron in strange places; like to rewire some electronics installed on a ceiling, about 14-16′ off the ground – not easy to get a traditional iron up there! I forget what I used but it was probably 60/40.

Sorry, the comment form is closed at this time.