Something that bugging me about USB-C fast charging

BUDFORCE

BUDFORCE

BUDFORCE

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OK so, first of all, in the scheme of things this isn't a huge problem, just something that has been niggling me and I cant figure it out.

Basically I have a LG Nexus 5x which has a USB-C connector and supports fast charge.

The OEM charger that came with the phone states output values of 3 amp @ 5v (or 15w) - when I plug that charger in, my phone displays "charging rapidly" on it, and charges, pretty damn quick.

I have struggled to find chargers that will charge my phone as fast, eventually found this:

Qualcomm Usb Quick Charger QC 3.0 18W Quick charge Portable Charger USB Wall Charger

I am not sure if links to 3rd party websites are allowed here but if you search on the big river, you'll find it. Anyway, that charger specifies output values of 3 amps at 5v, so in theory, puts out exactly the same amount of juice as the original charger, however, when I plug in that one, my phone just displays "charging" (note - not rapidly charging).

So why the difference?

I am using a high grade dedicated charging cable, so shouldn't be that.

Is it possible LG have put some kind of software in the phone to so it knows that it isnt the official charger?

Possible the output values on that Qualcomm charger are BS?

Help me, this is driving me up the wall!!!
 
There are a few different standards for fast charging including propitiatory variants - it is a bit of a mess and probably the reason some USB-C chargers and accessories keep being withdrawn from sale, etc. probably due to discovering a dangerous (maybe just hardware damaging) flaw when used with some devices which expect to be charged via a certain setup :(
 
Yup you are right, after a fair amount of digging I found this:

http://www.phonenews.com/intel-qualcomm-and-why-your-nexus-5x-6p-cant-quickcharge-with-usb-c-30860/

Basically the Nexus 5x and 6P although both made by different manufacturers are "sponsored" for lack of a better term by Google. For whatever reason, Google didnt include the Qualcomm Quickcharge (QC 2.0) standard on these phones. the QC 2.0 standard is a software handshake for both device and charger that can do all sorts including increase voltages down a standard micro USB cable connector.

Now the funny thing is, the Nexus 5x has a USB-C connection, which can naturally handle 3amp and 5v - however - because the phone doesnt adapt the QC 2.0 standard - the 3rd party charger cant make that handshake, and thinks the device isnt suitable, and as a safety feature, throttles the output down to 2amp.

That explains why for love nor money I have not been able to find a charger that will "fast charge" my device. I have also verified this just now using the ampere app. I plugged in the OEM charger and got a reading of around 1750ma. Plugging my Qualcomm charger in, I got about 1200ma. (Battery was around 60%)

I put in the serial number on the OEM charger and they are sold by LG electronics at guess what, £25 a go.....

Apparently there are a few 3rd party chargers that will fast charge a Nexus 5x (probably due to lack of the safety feature!) but they are few and far between.

Well I learned something new today anyway.
 
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BUDFORCE said:
Yup you are right, after a fair amount of digging I found this:

http://www.phonenews.com/intel-qualcomm-and-why-your-nexus-5x-6p-cant-quickcharge-with-usb-c-30860/

Basically the Nexus 5x and 6P although both made by different manufacturers are "sponsored" for lack of a better term by Google. For whatever reason, Google didnt include the Qualcomm Quickcharge (QC 2.0) standard on these phones. the QC 2.0 standard is a software handshake for both device and charger that can do all sorts including increase voltages down a standard micro USB cable connector.

Now the funny thing is, the Nexus 5x has a USB-C connection, which can naturally handle 3amp and 5v - however - because the phone doesnt adapt the QC 2.0 standard - the 3rd party charger cant make that handshake, and thinks the device isnt suitable, and as a safety feature, throttles the output down to 2amp.

That explains why for love nor money I have not been able to find a charger that will "fast charge" my device. I have also verified this just now using the ampere app. I plugged in the OEM charger and got a reading of around 1750ma. Plugging my Qualcomm charger in, I got about 1200ma. (Battery was around 60%)

I put in the serial number on the OEM charger and they are sold by LG electronics at guess what, £25 a go.....

Apparently there are a few 3rd party chargers that will fast charge a Nexus 5x (probably due to lack of the safety feature!) but they are few and far between.

Well I learned something new today anyway.
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Well, Qualcomm standard is proprietary and non-compliant with the USB standards.

There's a bunch of USB-C chargers with 5v/3a and PD support on Amazon which will work at a much lower cost though.
 
Mr Paul said:
Yes, you need a charger with USB C "PD".
Click to expand...
I think the 5X is actually not 'PD' enabled, which is a 'negotiation' between charger and phone. It's just using the standard 5v/3a enabled by the USB-C standard which was not legitimately allowed by USB 2/3 protocols before (hence the proprietary quick charge standard).

USB-C chargers with PD are more futureproof though and allow for even higher wattages than 15W. My Pixel 2 XL charges at 18W for example, at 9V/2A which isn't a USB-C standard but a specific PD agreed volatage/current agreed between phone and charger.

It's a bloody minefield out there :p
 
You need USB-PD chargers. I have the 5 port Anker USB C USB-PD charger and it charges my N6P rapidly. USB-PD and QC 3.0 and below sadly are not compatible. It's QC 4.0 however that can support both, but I've yet to see any chargers that supports it.
 
USB-C doesn't officially support QQC - if it's implemented, it isn't a certified cable. USB-C has its own fast charging method - power delivery. That's what your nexus device uses, along with the pixels and other devices (macbooks, new iPads).

You would need a charger that supports USB-C PD.
 
Orcvader said:
You need USB-PD chargers. I have the 5 port Anker USB C USB-PD charger and it charges my N6P rapidly. USB-PD and QC 3.0 and below sadly are not compatible. It's QC 4.0 however that can support both, but I've yet to see any chargers that supports it.
Click to expand...

MrRockliffe said:
USB-C doesn't officially support QQC - if it's implemented, it isn't a certified cable. USB-C has its own fast charging method - power delivery. That's what your nexus device uses, along with the pixels and other devices (macbooks, new iPads).

You would need a charger that supports USB-C PD.
Click to expand...

Sorry to nitpick but the 5X does NOT support USB-PD

It has the USB 3.1 enhanced power delivery specification which supports 5v/3a - USB-PD chargers will support this but you don't NEED a USB-PD charger to allow it. The OEM 5x charger was 5v/3a but not PD.

TBH OP would be best served picking up a USB-PD charger anyway so I don't know why I'm arguing :D
 
chanjy said:
Sorry to nitpick but the 5X does NOT support USB-PD

It has the USB 3.1 enhanced power delivery specification which supports 5v/3a - USB-PD chargers will support this but you don't NEED a USB-PD charger to allow it. The OEM 5x charger was 5v/3a but not PD.

TBH OP would be best served picking up a USB-PD charger anyway so I don't know why I'm arguing :D
Click to expand...

That's really strange, because I've used my 6P charger to charge my Pixel 2XL and it says "charging rapidly" - I thought the Pixel 2XL needed a charger with PD to fast charge
 
It still counts as PD, the annoying thing is there's different voltage profiles and it's not required to support all of them. The 5X/6P supports only the 5v profile, while the Pixel is both 5v and 9v. The Nintendo Switch charger uses 5v and 15v. I think Apple's one supports 5v 9v and 20v if I remember correctly.
 
FWIW, I have replaced various plug sockets in my home with the BG USB sockets, rated at 3.1A. These charge both my Nexus 5x "Rapidly".
However, they don`t always say charging rapidly straight away. Sometimes it will say "Charging" for a few moments, before switching over to "Rapid Charging" once the display sleeps.
 
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