iPhone 8/Plus Is a usb c to lightning required for fast charge?

[dukebound85]

I see many adapters for higher watt chargers. It has both a usb a and usb c output with the following specs:
Output USB C(PD): 5V-3A; 9V-3A; 12V-2.5A;
Output USB A(QC): 5V-3A; 9V-2A; 12V/1.5A;
Total Output(USB C + USB A): 45W

Some questions:

- Is fast charging on iPhone only supported from usb c to lightning that has PD?
- Does the iPhone only support certain charging profiles? or will any combination of voltage/amps work?
- Is any "faster" charging accomplished with the USB A interface?
- Does anyone have apps that measure power of charger as charging?

Thanks!

 

[Slartibart]

I googled that for you… ?

 

[Shirasaki]

The only app that could measure charging power was coconutbattery back in 2014 or so. Dunno what’s happening now.
As for cable, USB-C port has more pins for power than USB-A, hence potential for delivering more power. It’s just so much so that a phone don’t really need 100W power delivery so there doesn’t seem to have much difference. This is also the reason why when connecting your USB-C port iPad to a computer that has USB-A port, iPad won’t be recharged.

 

[dukebound85]

I googled that for you… ?

that doesn't answer my questions. I have read that prior to posting

if a iPad charger (higher wattage usb a) does charge iPhone faster, would even higher wattage usb a charges charge faster?

 

[Shirasaki]

that doesn't answer my questions. I have read that prior to posting

if a iPad charger (higher wattage usb a) does charge iPhone faster, would even higher wattage usb a charges charge faster?

No. Instead, the power control chip inside your device will limit the power sent into your device for recharging in order to avoid heat and overcurrent. Power brick itself may also include chips to negotiate with target device so a safe charging can be performed.

 

[now i see it]

An iPhone can only charge as fast as its design spec. Charging with a 200 watt charger will charge the battery with the same amount of current as when using a 20 watt charger.
All iPhones can accept a charge greater than the output of the old dinky 5 watt charger - up to a point. When they hit their limit, they can't charge any faster

 

[dukebound85]

An iPhone can only charge as fast as its design spec. Charging with a 200 watt charger will charge the battery with the same amount of current as when using a 20 watt charger.
All iPhones can accept a charge greater than the output of the old dinky 5 watt charger - up to a point. When they hit their limit, they can't charge any faster

do you know what charging profiles are supported?

apples says min of 20W that supports PD spec

If charger is say 30W that is PD, will iPhone charge at 30W? and so on as long as meets PD spec? hence one of my initial questions

 

[now i see it]

It depends on each iPhone. The newer ones can charge much faster than the old iPhones.

 

[Slartibart]

D

that doesn't answer my questions. I have read that prior to posting

if a iPad charger (higher wattage usb a) does charge iPhone faster, would even higher wattage usb a charges charge faster?

USB-C can handle higher data transfer rates and higher current/voltage.
Power Delivery (PD) is a specification for handling higher power and allows a range of devices to charge quickly over a USB connection. It operates by facilitating a conversation between two devices to negotiate a power contract so they can determine how much power can be pulled from the charger. Power Delivery starts at the 5V setting and is configurable up to 20V. Using a standard USB-C cable, it can handle up to 60W, and will go up to 100W using a designated EMCA cable.
USB-A-to-Lightning will run at lower voltage.

This is also the reason why when connecting your USB-C port iPad to a computer that has USB-A port, iPad won’t be recharged.

It charges. Just way slower.

 

[Slartibart]

- Does anyone have apps that measure power of charger as charging?

more accurate is something like this.

 

[now i see it]

Yeah, charging and discharging current was always available for developers to display in their battery apps up to iOS 9, then Apple took the privilege away in iOS 10 and never gave it back. The info is still available to apple but nobody else. Such nice helpful guys.

 

[MacCheetah3]

Some questions:

- Is fast charging on iPhone only supported from usb c to lightning that has PD?
- Does the iPhone only support certain charging profiles? or will any combination of voltage/amps work?
- Is any "faster" charging accomplished with the USB A interface?
- Does anyone have apps that measure power of charger as charging?

Thanks!

- No, USB A is also capable of fast charging. Although, as some members already mentioned, the maximum speed limit (i.e., power transfer) will vary by device, cord/cable, connector, and adapter (“brick”) combination
- I’m not certain, however, I assume the adapter must conform to either standard USB or USB-PD spec.
- Yes
- coconutBattery does show a charging rate when an iPhone/iPad is connected. How accurate? ¯\_(ツ)_/¯

Without any technical measuring, using a 10 watt adapter (Apple original for iPad 2) the time required for a full charge indeed appears about half as long as when using the 5 watt adapter. Using the charger (USB-A connector) included with my Samsung Galaxy Tab S5e purchase, my iPhone’s charging rate seemingly increases another 10 or so (i.e., more than the Apple 10 watt) — which may be an iPhone X fast charging limit as well as that of the adapter.

 

[NT1440]

I was always able to charge faster from my iPad charging going back to the 6s, however I think that only meant it would use 12w instead of 5/10w from the iPhone charger.

The “fast charging” feature is a little bit of a different beast however and I’m not certain what the upper limit in wattage is when everything else is within spec. Obviously there’s a compromise that has to be made between the fastest possible charging and the overall lifespan of the device m.

 

[MacCheetah3]

@NT1440 Well, up to 1.5 hours vs. up to 3.5 hours to charge (probably 12W vs. 5W) certainly feels like fast charging to me. Any who… You’re correct though about...

the “fast charging” feature is a little bit of a different beast

Twelve watts isn’t even at the minimum for the latest iPhones — or so is the fast charging power adapter requirement.

2. You need a 20W or higher power adapter to fast charge your iPhone 12.

Fast charge your iPhone - Apple Support

Fast charge some iPhone models.

support.apple.com

 

[dukebound85]

I am reading that a usb a power adapter >20watts for instance having QC 3.0 may very well only charge at the 5A/1V rate due to not having the QC 3.0 in the iphone

I wonder why the iPad charger increases the charge rate when using usb a? I imagine this increase in charge rate os only from apple power adapters?

 

[1BadManVan]

that doesn't answer my questions. I have read that prior to posting

if a iPad charger (higher wattage usb a) does charge iPhone faster, would even higher wattage usb a charges charge faster?

It didn’t answer any of your questions if you didn’t bother to read it.

Quote from that link ”Fast charging works when you use an Apple USB-C to Lightning cable and one of these adapters”

So will it charge faster over a 10 watt charger vs 5? Yes. But to get the actual advertised fast charge, you need a USB c to lightning with a properly supported charging brick

 

[dukebound85]

It didn’t answer any of your questions if you didn’t bother to read it.

Quote from that link ”Fast charging works when you use an Apple USB-C to Lightning cable and one of these adapters”

So will it charge faster over a 10 watt charger vs 5? Yes. But to get the actual advertised fast charge, you need a USB c to lightning with a properly supported charging brick

I read it...you didn't understand my question

official "fast charge" aside that requires usb c, you say a 10W charges faster than a 5w, ok. Now will a 20w charge faster than a 10w over usb a? what about a 30w? at what point is it not going to charge faster?

We all recognize the 12watt iPad charger charges a phone faster than the 5watt over usb a. When does this stop being the case?

 

[MacCheetah3]

When does this stop being the case?

I found the following, a very interesting article performing charging tests using Apple’s 61W adapter.

Which USB PD fast charger is needed? iPad Air3/Mini 5 charging test

On the 2019 Apple special event in March, there was no hardware product released. But before the event, Apple quietly put two new iPads on the official website, namely iPad mini 5 and iPad Air 3. Both the iPad mini 5 and the iPad Air 3 use the powerful Apple A12 processor. In addition to the...

www.inviolabs.com

In summary, the max charge rate essentially correlated to the included/internal battery’s power transfer capability.

For example, the iPhone 12 Pro Max has a 14.13-watt-hour battery, hence the 20W adapter (general) requirement to fast charge an iPhone 12… or the iPad Air (4th generation) with its 28.6-watt-hour battery seemingly can’t benefit beyond a 30W adapter for max charging speed… and so on.

 

[Slartibart]

I read it...you didn't understand my question

official "fast charge" aside that requires usb c, you say a 10W charges faster than a 5w, ok. Now will a 20w charge faster than a 10w over usb a? what about a 30w? at what point is it not going to charge faster?

We all recognize the 12watt iPad charger charges a phone faster than the 5watt over usb a. When does this stop being the case?

As it was written several times before, it depends on all parts involved. The basic gist of how it works is that two USB-PD enabled devices negotiate a power contract, or a handshake, when they’re plugged into each other. They discuss how much power the source can support, as well as how much power the device being charged can handle. The standard for USB-C devices without PD is 5V/3A, but the voltage is configurable depending on the device and can go as high as 20V/5A (with an EMCA cable). Then they settle on a compatible rate which both the supply and device support and the charging (or discharging) begins.

just connecting a charger with a higher max W output will not simply charge any device with a USB-PD supported connection faster (btw. Qualcomm’s Quick Charge isn’t compatible to USB-C spec. PD).

Here - I googled again ? - maybe this helps.

 

[TheIntruder]

I read it...you didn't understand my question

official "fast charge" aside that requires usb c, you say a 10W charges faster than a 5w, ok. Now will a 20w charge faster than a 10w over usb a? what about a 30w? at what point is it not going to charge faster?

We all recognize the 12watt iPad charger charges a phone faster than the 5watt over usb a. When does this stop being the case?

There's no way to feed an Apple device with 20W via USB-A. QC3 is capable of 36W, but Apple has not employed QC, and is unlikely to adopt Qualcomm's proprietary standard over USB-PD. QC4 is capable of higher power, and is compatible with PD, but via USB-C, not A. Just as notable is the fact that QC3 over USB-C violates USB spec, so any product that claims that capability is best avoided.

As a practical matter, no iOS device (i.e. not MacBooks) has been demonstrated to draw more than ~30W sustained, and that is the 2018 and later iPads Pro via USB-PD. That is the limit, and only via USB-C.

So the answer to the original question is yes, a USB-C source is required to fast charge an Apple device.

 

[HDFan]

charging and discharging current was always available for developers to display in their battery apps up to iOS 9,

There are hardware devices that you can purchase that will give you the current information. This is what I use, but it is discontinued:

PLX Devices Legion Meter USB Power Meter with Integrated OLED Display. Accelerate Your Charge Speed up to 92% Faster.

PLX Devices Legion Meter USB Power Meter with Integrated OLED Display. Accelerate Your Charge Speed up to 92% Faster.

www.amazon.com

just connecting a charger with a higher max W output will not simply charge any device with a USB-PD supported connection faster

Maxtech has a video about the differences between various charging methods. More watts does not necessarily mean a faster charge. Screen shot from 3:37:

 

[MacCheetah3]

Helpful video. His tests remind:

• Wireless is much less efficient
— Need I say more? Okay. If every bit of speed is very important, wired is best.
• “Fast charge” is only up to 50% of the battery capacity
— The charging rate significantly ramps down at 50% then at 80% to preserve battery health
• Not all power adapters are the same
— How much and quickly/often they negotiate the rate with the device varies by device and adapter
• Performance varies by device model
— Each iPhone model has a different battery with different capability (i.e., an iPhone 12 mini can’t charge as fast as a 12 Pro Max)
— This is also shown in tests in the article I linked to earlier.