Imperf3kt wrote: ↑
Wed Oct 23, 2019 9:49 pm
What was wrong with using a 9v charger for a 9v device or a 20v charger for a 20v device? Why must the charger be 'smart' and supply multiple voltages at all?
What happens when some complete nincompoop plugs the 20V charger into the device which requires 3V? Devices are supposed
to include some level of protection against that, but it is rarely 100%. Does the device start overheating, then catch on fire? Once on fire does it short out the power supply and cause it to catch on fire? Does it take an hour to do this, thus giving the person time to go to another room and start ignoring the item and not realize the situation until it is a full on structure fire?
What about when you've got some $random_device and you don't know its power requirement? Do you throw it out due to being unable to figure out an appropriate power supply?
Years back there was at least one attempt to standardize power supplies such that each voltage used had a distinct connector. One of the problems was that there are only so many variants of barrel connector you can make. They were distinct sizes, but the loose tolerances required meant incompatible devices had a distinct chance of being able to be plugged in.
Keeping a device paired with an appropriate power supply is good, but the real world has shown that this never works. What of cellphones? If you're isolated at an airport in the middle of nowhere would you rather be able to borrow someone else's charger or have no way to charge your phone which you forgot the power supply for?