Official Power Supply Question

[gtechn]

Hello. I know this is a really, really odd question. I have a new official Raspberry Pi power supply coming, and I am wondering what would happen if I wasn't using my Pi and used it to charge a phone (or if someone got it mixed up as a phone charger). Phones charge at about 2.1A, but the charger outputs 3A. Will it step down the voltage to 2.1A or 1A automatically, or will it always output 3A at slight risk of damaging a phone?

[jbudd]

I don't know about the new PSU because my phone has micro USB not USB-C.
However my phone will not charge from the original official Raspberry Pi power supply. It doesn't blow up either, just doesn't charge

[W. H. Heydt]

Hello. I know this is a really, really odd question. I have a new official Raspberry Pi power supply coming, and I am wondering what would happen if I wasn't using my Pi and used it to charge a phone (or if someone got it mixed up as a phone charger). Phones charge at about 2.1A, but the charger outputs 3A. Will it step down the voltage to 2.1A or 1A automatically, or will it always output 3A at slight risk of damaging a phone?

Any device will only draw as much current as it--wildly anthropomorphizing here--wants. You could hook up a 100A supply to your phone or a Pi and the phone or Pi would still only draw 2A to 3A. (In practice, don't do this. If there is any sort of electrical fault in the device, it could short the 100A PSU and the results would be...spectacular. And not in a good way.)

Many's the time I've used Pi PSUs to change phones or tablets with no issues at all. Indeed, given the price and quality, I wouldn't be surprised if a great many Pi 3A PSUs aren't bought specifically to be used as chargers.

[solar3000]

the pi supply won't fast charge your phone though. if you plug it in, your phone might complain.

[hardwaremack-orginal]

my Samsung note 8 will only charge at max 300ma with this new usb c 3a charger... annoying... but expected.
my Dollar Tree $1 dollar 1000ma 110v plug in charger pulls 1047ma!! lol with my phone... go figure.
if dollar tree ever sells these again i will buy a whole case.

[Andyroo]

my Samsung note 8 will only charge at max 300ma with this new usb c 3a charger... annoying... but expected.
my Dollar Tree $1 dollar 1000ma 110v plug in charger pulls 1047ma!! lol with my phone... go figure.
if dollar tree ever sells these again i will buy a whole case.

Watch Big Clive on YouTube and as of 3rd July, he describes his channel in part as

The trashiest electronic channel on YouTube. We test and use affordable electronic soldering equipment and tools to build, teardown, modify (and sometimes destroy) random electronic stuff.

Though based this side of the Atlantic he tests a lot of cheap power banks and saved me a fortune over the years

[rpdom]

Though based this side of the Atlantic he tests a lot of cheap power banks and saved me a fortune over the years

Clive has cost me a fortune with some of the stuff he reviews. I just had to go out and buy it (but not "Fanny Flambeaux" ).

[Andyroo]

...
Clive has cost me a fortune with some of the stuff he reviews. I just had to go out and buy it (but not "Fanny Flambeaux" ).

Oh - I had forgotten that one

As for buying things - I need some new lights in the loft and he just reviewed some today - perfect timing

[B.Goode]

Phones charge at about 2.1A, but the charger outputs 3A. Will it step down the voltage to 2.1A or 1A automatically, or will it always output 3A at slight risk of damaging a phone?

The 'A' in expressions like 2.1A is an abbreviation for Amperes, often contracted to 'amps'. An Ampere is a unit of current, not voltage.

[rpdom]

As for buying things - I need some new lights in the loft and he just reviewed some today - perfect timing

Those LED strip lights looked pretty good and not too expensive. IIRC the 20W version he reviewed was around 8 quid.