JUST HOW DODGY ARE CHEAP USB CHARGERS ANYWAY?
https://hackaday.com/2023/11/03/just-how-dodgy-are-cheap-usb-chargers-anyway/?fbclid=IwAR2dtHu9mUJjrqO9ZLwBR12ogPwyFiBU5I58wmtBR1Cp-mKd5phKb6zi3mc

I was cleaning up and found an old Six-Letter usb charger that I remembered having removed from service but I couldn’t remember why. I opened it up and got a clue right away.

The unpopulated spots on the bottom are for the very important AC line noise filter to keep the high frequency switching pulses from the switch mode power supply from escaping into the house wiring and causing a myriad of interference to tv/radio reception and audio systems (among other things). In many cheap and nasty power supplies that have gone through quality fade, you will find this same issue. What should have been there is a common mode choke that looks like a small transformer, and a safety capacitor.

I opened this unit expecting it to be well built, and it didn’t disappoint. It even threw in a few surprises.

This is IKEA’s smallest USB power supply intended for continuous use to power accessories like lights or ornaments. It only delivers 5V at 1A, so is less suited to high demand items like smartphones and tablets. But it will happily charge and power smaller items.

I’ve always recommended the use of good quality branded USB power supplies for safety reasons. I regard IKEA power supplies as some of the most robust and safest units available. And they’re NOT expensive compared to the fashion brands.

Laturien käyttö altistaa sähköiskulle ja toisessa tapauksessa myös tulipalolle.

https://www.is.fi/digitoday/art-2000009604219.html