Yup. Usually the device being charged can scale down the power throughput so it’s not getting 60W+ if it’s not able to handle it.
That’s the core of charging management: The charged device controls the process, not the charger.
Anything else won’t work if you think about it.
In this thread: people who don’t understand what power is.
Power isn’t something that is “pushed” into a device by a charger. Power is the rate at which a device uses energy. Power is “consumed” by the device, and the wattage rating on the charger is a simply how much it can supply, which is determined by how much current it can handle at its output voltage. A device only draws the power it needs to operate, and this may go up or down depending on what it’s doing, e.g. whether your screen is on or off.
As long as the voltage is correct, you could hook your phone up to a 1000W power supply and it will be absolutely fine. This is why everything’s OK when you plug devices into your gaming PC with a 1000W power supply, or why you can swap out a power-hungry video card for a low-power one, and the power supply won’t fry your PC. All that extra power capability simply goes unused if it isn’t called for.
The “pushing force” that is scaled up or down is voltage. USB chargers advertise their capabilities, or a power delivery protocol is used to negotiate voltages, so the device can choose to draw more current and thus power from the charger, as its sees fit. (If the device tries to draw too much, a poorly-designed charger may fail, and in turn this could expose the device to inappropriate voltages and currents being passed on, damaging both devices. Well designed chargers have protections to prevent this, even in the event of failure. Cheap crappy chargers often don’t.)
Great write up! Definitely filled in the info I only know a little about.
In this thread: people who don’t understand what power is.
Oh, please enlighten us, oh wise one. You might want to google “power draw” before you reply.
I guess he should have included the subtitles.
Have you ever heard the story of Darth Plagueis the Wise?
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.
Usually
Is there some exception to USB-C im not aware of? Am i putting myself in danger using high power chargers to charge low power devices?
No, they do a handshake through the USB connection and negotiate the best charging wattage.
And to add : if the handshake fails, or no common voltage can be decided, it will stay at 5v
If you use really cheap 3rd party chargers there is a possibility.
i charge most things with usb-c. for everything else, there’s mastercard.
I am a usb-pd believer. My phone, laptop, soldering iron, … All usb type-c with usb-pd capability, all running from my laptop charger that can do 5,12,19 and 20v
I’m waiting for a 138kV three phase USB-C for EV instant charging.
I’m waiting for the MagSafe variant myself.
Miniware TS80?
I’m with you, usb c all the things. Can you recommend a good pd powerbank?
I’ve got one of these and it works pretty well. I’m sure there are better ones out there and a second USB c port would be nice, but it’s affordable. https://a.co/d/9JzWOi4
Pine64’s pinecil v2 actually. But it uses the same tip as miniware’s soldering irons.
Cant help with powerbank though haha
I have a 65W usb c charger that I use for basically everything
Im charging everything with my Steam Deck’s charger. Having to take care of only one charger makes life a lot easier
Yes, but my phone negotiates a slower speed with the laptop charger than its own.
I’ve charged numerous devices with the Nintendo Switch charger too.
I’ve been paranoid to do that since I’d heard that the switch charger is non-standard, but that may just be Nintendo propaganda.
No, this is correct. The switch and adaptor use voltages that arent standard to the usb-pd protocol. However, using the adaptor on your phone should be fine as both need to accept the voltages before it switches
It doesn’t matter, USB-C won’t use a voltage that’s in excess of the voltage the receiving device can accept, so even if the cable is theoretically capable of a higher voltage it won’t matter. Just like you can’t overcharge your phone battery anymore, the charging will just stop automatically at 100%.
The switch cable won’t carry data which is odd, but it won’t break your phone and you probably don’t need data most of the time anyway.
I charge my headphones with a laptop charger
Yep, best thing ever, I bought a GaN charger, 100W 3 USB-C and 1 USB-A. It’s small and light. I carry it around everywhere. I even bring it at my client’s office instead of the power brick they gave me since it’s so small.
Just make sure you have plenty of wattage. For instance, my job laptop uses a 65W adapter. If I want to charge this at the same time as my phone, I would need at least 90W to cover everything (65+25). So I have more power than necessary In order to be able to charge everything at once. Also, make sure to. Heck the adapter on how it distributes power trough the ports. My configuration could not be supported on a 3 port if for example they decided to split the power 55+45. But mine is 65+35 with 2 ports so I’m fine.
Having my mouse (Logitech mx something) currently on my 135W Lenovo usbC laptop charger with no problems. I try to charge everything with type C usb-pd.
my laptop charger is round and my phone is usb-c
my laptop has usb-c but it doesn’t seem to charge it
I have a dell laptop. Barrel charging port, but the USB-C port will charge it too… Just very slowly with a 33W phone charger instead of the 130W laptop charger.
What is that picture?
Explosion
Ah… I thought it was some kind of hamster
It was
Do you charge your hamster with a usb c cable?
My laptop doesn’t even have an usb type c charger
Yes. Also vice-versa.
I would … after I guy this year’s iPhone … and a new laptop.
Seriously, though, why not? I did get my kid one of the Anker gallium arsenide chargers so he could do exactly that
But I’ll also go the other way - who charges their phone on the lowest power charger? I have a dual charger with total 2.1a, and it fully charges both my phone and watch overnight
I mean, for overnight charging you could probably go as low as 0.5A. Slow charging is better for your battery in the long run, afaik.
I have ACCA installed on my rooted Android phone and have it set to charge at 700mAh, to go easy on the battery. So no matter what charger I use, it always charges slowly lol.
I’ve got wireless charging pads/stations/car holder everywhere. Super convenient to just drop your phone down and keep it charged.
My phone’s usb C port got so loose after ~2.5 years that cables would just fall out, so I fully committed to QI charging to preserve whatever is left of that port for things like data transfer.
