They all have a designed max current that they will operate at. If you have a 5 volt 2 amp power supply, the most you will get out of it is 2 amps, regardless of what the load will accept. Of course, up to the max it can supply, it does no regulation. So, rather than regulation, lets just say it is a hard limit.
Quite true. But it becomes just a matter of semantics. Some refer to these as chargers, some simply power bricks. Yes the better term is power supply. Which I try to remember to use. Sorry for the lapse. But common use means that for USB, the charger and power supply terms are used interchangeably.
If the supply is designed correctly and regulated properly, it will limit current based on keeping the voltage at the correct level. Yes I have seen them that just shut off to keep from a melt down… but even that is a very simple kind of regulation. Right? Bottom line is it will not harm the device being charged by giving it more current than it can accept. As an example, I have connected devices that will accept 20 volts at 5 amps to a supply that has a max rating of 5 volts at 2.5 amps. My meter shows it is delivering 5 volts at 2.4 amps…or less. It does not shut down and keeps the voltage relatively close to 5 volts. I guess that means it is regulating the max current to stay within it’s design limits.
I fully agree. 100%. I thought I was trying to say just that. Sorry if I was not clear.