diy Fast charging

[Doubt asker]

I know it's quite weird doubt ; how to activate fast charge state in adapter without phone as I saw adapter switches to 12v when charged with a compatible phone. I want to do it myself to see if I can vary the speed of cooling fan with this. 

 

Adapter is Moto G4+ 32gb compatible one

[Doubt asker]

Nothing just some diy stuff for the future

[Huntsman]

There's 2 types of fast charging: simple high current draw by the device or charger provides higher voltage.

 

If it's the first one, it's up to the device to decide how much current to draw, the charger merely provides information about how much power it could provide.

 

The later requires complicated communication between the device and the charger to negotiate/verify that both parties are capable of that high voltage.

[r4tch3t]

It's not too complicated, mearly different voltages on the data lines.

Link

link To PDF  for a charger IC  shows the voltages you need for the different output voltages.  page 9 I think

[Doubt asker]

On 06/11/2016 at 0:45 PM, Huntsman said:

There's 2 types of fast charging: simple high current draw by the device or charger provides higher voltage.

 

If it's the first one, it's up to the device to decide how much current to draw, the charger merely provides information about how much power it could provide.

 

The later requires complicated communication between the device and the charger to negotiate/verify that both parties are capable of that high voltage.

Yeah I understand but is there any way to communicate with the charger by some DIY stuffs like with an IC if yes I need an IC number. Thanks really appreciated. 

[Huntsman]

Don't think there is (legally) any chips that handles the communication on the receiver side on sale. This is all Qualcomm's proprietary tech supported on the chipsets itself. Think you would have to reverse engineer and emulate the communication on a microcontroller to get it.

 

Looking at this article. Seems like Quick Charge 2.0 only supports 5v, 9v and 12v, whereas 3.0 supports 3.2v up to 20v but not sure about the increment resolution. But alas, total power output is 18W.

 

Btw, why a phone charger? Would be so much easier with a cheap chinese variable voltage adapter.