Not usually, but all the time. It’s part of the USB standard to negotiate the power that the device and even the cable can handle.
When all USB could do was 5V I already didn't trust any charger but mine - I couldn't believe people dared to connect their devices to charge into any public USB chargers.
Now that they can go up to 20V, and we have to trust everything will work with the negotiation and wiring to get the right voltage, it's even scarier!
Will go up to 48V (240W) with the next USB-PD standard.
But as long as it's reputable hardware that actually implements the starndard, I'm not too worried.
48V and we're back to POTS (plain old telephone system) voltages :-)
I agree, but that's the problem even from reputable sources, glitch happens. Old 5V-only chargers would need much more things to go wrong to fry our devices. A 20V (or 48V !) one is just a small (sw or hw) glitch away to zap a device that doesn't support such voltages.
The USB standard is usally really robust and the changes of SW errors is small. If you have a good brand laptop it will probably come with very reliable charger as well. I really don't worry about it.
Not usually, but all the time. It’s part of the USB standard to negotiate the power that the device and even the cable can handle.
When all USB could do was 5V I already didn't trust any charger but mine - I couldn't believe people dared to connect their devices to charge into any public USB chargers.
Now that they can go up to 20V, and we have to trust everything will work with the negotiation and wiring to get the right voltage, it's even scarier!
Will go up to 48V (240W) with the next USB-PD standard.
But as long as it's reputable hardware that actually implements the starndard, I'm not too worried.
48V and we're back to POTS (plain old telephone system) voltages :-)
I agree, but that's the problem even from reputable sources, glitch happens. Old 5V-only chargers would need much more things to go wrong to fry our devices. A 20V (or 48V !) one is just a small (sw or hw) glitch away to zap a device that doesn't support such voltages.
The USB standard is usally really robust and the changes of SW errors is small. If you have a good brand laptop it will probably come with very reliable charger as well. I really don't worry about it.