Teardown of an IKEA Koppla USB power supply.
Why Hacker News recommends it
Cited as a teardown of a well-made, safe USB charger, and as evidence for why quality chargers matter.
What it is
Big Clive takes apart an IKEA Koppla USB power supply to assess its safety, looking at isolation and transformer construction.
Recommended by 2 HN commenters across 2 different months, 2017 to 2021.
What Hacker News said
Recommends BrailleHunting · 2017-03 · on “Man dies charging iPhone while in the bath”
TL;DR: spend the $19 to buy a real, big brand USB charger because they have more to lose than grey market no brand. Tragic. Probably cheap USB without mains isolation or maybe enough water dripped down length of cable and socket to create a circuit, because USB is supposed to be 5V DC. Watch these USB charger teardown horror-shows to further understand why it's rational to pay for proper, authentic CE+UL, high-low isolation and quality components (ie insulated tape in transformers): [LINK] [this video] [LINK] [LINK] [LINK] [LINK]
Recommends fnord123 · 2017-04 · on “A quick look at the Ikea Trådfri lighting platform”
Also of interest is this teardown of the Koppla USB power supply: [this video] It's also a pretty darn good piece of kit.
Cites Daneel_ · 2021-08 · on “Apple iPhone charger teardown: quality in a tiny expensive package (2012)”
Big Clive also did a fairly comprehensive teardown of the IKEA charger and was pleasantly surprised with the design: [this video] He also confirms that the control chip is a 1699-02.