[vlovich123]

That's not how standards work. If a cable or charging block is out-of-spec it can easily pose HW damage risks or fire hazards. It's impossible to consider every possible way this stuff can be broken.

Take for example https://gizmodo.com/a-google-engineer-is-publicly-shaming-cr...

OnePlus USB-C cables work fine with OnePlus devices but can damage any other USB-C device.

Another example where a USB-C cable destroyed his USB PD analyzer & his chromebook ports: https://www.amazon.com/review/R2XDBFUD9CTN2R

This was because the cable was completely miswired.

There's also numerous reports out there of how crappy charging blocks are fire hazards if driven at the full level they advertise.

https://globalnews.ca/news/3365247/electronic-charging-devic...

It's not totally unreasonable for a responsible manufacturer to either outright ban charging from unknown blocks/cables or to fallback to a trickle charge that disabled the highest-speed charging.

Since there's so many the only way to do this is to maintain a whitelist of good chargers at the expense of fast charge not working with an arbitrary number of chargers. You could think "well, just warn the user & give them a choice." However, the majority of users would just learn that most of the time it's OK & just hit "OK" blindly even when connecting to new chargers they don't know about. Also the news reporting would still be the same & wouldn't capture the nuance of using a third-party charger since news cycles are more instant & don't allow the necessary amount of time for engineers to receive the unit & perform diagnostics to figure out what happened.

[wnevets]

>https://gizmodo.com/a-google-engineer-is-publicly-shaming-cr...

That's exactly what I thought of when reading the GP. There is some absolute garbage out there being sold.

[jjoonathan]

There are also manufacturers using the existence of such garbage as a scapegoat.

For instance, the fitbit ionic battery plague is caused by shorted MLCCs -- but they still try to blame it on 3rd party chargers every time they get an RMA.

[mark-haus]

That’s why circuit designers almost always create charging and power circuits with over voltage and current protections into fragile electronics. Certainly on a system as fragile and complex as a cell phone. This isn’t an excuse, this is bucking trends of circuit design that has existed for decades. And it’s even easier to prevent in wireless transmissions than physical ones because wireless requires careful tuning of resonance to work efficiently. The circuit to prevent this would be simpler than this handshaking one to detect “ok” chargers.

[shittyadmin]

> Another example where a USB-C cable destroyed his USB PD analyzer & his chromebook ports

That sounds to me more like a shitty design on both of those.

Short of sending hundreds of volts and causing arcing, this should be preventable, should it not?

[Arnt]

That cable supplied voltage on the ground line. Quite some WTF factor on that, but also difficult to protect against.

[zaarn]

You can protect against reverse voltage, ie, voltage from the ground line.

A simple diode is the easiest way, using various power MOSFETs can reduce the voltage drop induced and you can even build a circuit that allows charging the battery and supplying power on the same connectors while also protecting against reverse voltage.

It's neither hard nor expensive.

[Arnt]

TIL.

Are you saying that it's possible to protect against all kinds of shenanigans on the ground line even if the device has no other ground, or only against negative voltage?

[zaarn]

There is only reverse voltage and over voltage.

Ground is basically your reference, if your ground has potential above your voltage input, you're in reverse voltage, if your ground is too far below your voltage input, then you're in over voltage.

Both can be detected and prevented from causing damage via various means on both sides of the usb plug.

Overvoltage can usually be solved by having a Zener diode within acceptable overvoltage short the thing to ground and blow out a fuse, this will cut the circuit and prevent further damage.

I recommend this video from GreatScott: https://www.youtube.com/watch?v=7Tk5ghH_U2s

[discreditable]

Non-shitty devices will behave well, but shitty ones won't. That's the problem.

[Dylan16807]

Some devices will break when you draw advertised levels of power. That's just a fact of life, and isn't something you should try to fix with DRM. It's not a very common thing.

It also doesn't damage the device itself.

The backwards cable is worth noting but not relevant to a system that's fundamentally AC.

Outside of some kind of massive EMP, nothing a wireless charger does should be able to hurt your battery.