# Wiring a 5A USB charging port into a 12V circuit

#### EnJoneer

Joined Oct 11, 2016
7
Hi,
This is my first time posting here but I think I might need to ask for a lot of help with an upcoming project of mine.

I have a Huawei P20 Pro and it supports 5A supercharging. I want to wire a 5A USB port into a 12V system I am designing for a campervan conversion. The reason being that I don't want to have to spend loads of money on an inverter for mains power if I don't need to.

I want to know whether it is possible to purchase a 5A USB charging port, and if not then how I might get around this and make my own? I will be running the 12V system off a 12V MPPT controller with a solar feed.

Sorry if my question is a little dumb, I hope you guys can give me some help!!

#### mvas

Joined Jun 19, 2017
538
Can you provide a URL link to the exact device that you are discussing?
Do you have a 5 Amp USB Charger, that only operates from 120 Volts,
and now you need a 5 Amp USB Charger that operates from 12 Volts?

Is there a special protocol for the 5 Amp USB Charger for your Huawei P20 Pro device?

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#### mvas

Joined Jun 19, 2017
538
You can buy a small 12 Volt DC to 120 Volt AC Pure Sine Wave Inverter for (approx) $30.00 #### iONic Joined Nov 16, 2007 1,650 I can understand why you don't want to spend much money after paying for that smartphone. This will do everything for you! 120VAC and USB ports with 4.2A output for$30 just as mvas stated. Trying to design and build something will almost surely cost you more $$and certainly far more time! The Solution #### mvas Joined Jun 19, 2017 538 I can understand why you don't want to spend much money after paying for that smartphone. This will do everything for you! 120VAC and USB ports with 4.2A output for 30 just as mvas stated. Trying to design and build something will almost surely cost you more$$ and certainly far more time!

The Solution
"5 Amp super-charging" over USB is not a Standard, right?
How exactly did they accomplish that?
I would not what to connect any non-certified ( prototype ) charging circuit to my cell phone.

#### iONic

Joined Nov 16, 2007
1,650
"5 Amp super-charging" over USB is not a Standard, right?
How exactly did they accomplish that?
I would not what to connect any non-certified ( prototype ) charging circuit to my cell phone.
The manual I have for a Huawei P20 Pro doesn't even mention "supercharging." Has the battery technology advanced to safely do this? And how good is it for the battery in the long run?

And No, EdJoneer, the question is not dumb.

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#### EnJoneer

Joined Oct 11, 2016
7
Can you provide a URL link to the exact device that you are discussing?
Do you have a 5 Amp USB Charger, that only operates from 120 Volts,
and now you need a 5 Amp USB Charger that operates from 12 Volts?

Is there a special protocol for the 5 Amp USB Charger for your Huawei P20 Pro device?

^^ this is the exact starter kit I will be using. I want to be able to save myself some money and remove the need for an inverter in the system by having a 12V USB charge port for my phone. My phone supports 5A supercharging at 230V with the standard phone charger, I just want to wire a USB charging port into the 12V system that supports the 5A charging capability, but I can't find any products capable of doing so online.
As for the special protocol... I honestly have no idea, I was hoping to find info out from you intelligent people.

Thanks for the quick reply!

#### EnJoneer

Joined Oct 11, 2016
7
You can buy a small 12 Volt DC to 120 Volt AC Pure Sine Wave Inverter for (approx) $30.00 I have considered this, they just looked a bit dodgy. Then again, whatever I end up wiring might not be much better! Thread Starter #### EnJoneer Joined Oct 11, 2016 7 I can understand why you don't want to spend much money after paying for that smartphone. This will do everything for you! 120VAC and USB ports with 4.2A output for$30 just as mvas stated. Trying to design and build something will almost surely cost you more  and certainly far more time!

The Solution
I was considering buying one of these but had read that some devices have complications working from anything but a pure sine wave inverter?
Also, would it cause any problems to just splice the 12V cable on this and wire it into a 12V system directly?
Thanks for your help!

#### EnJoneer

Joined Oct 11, 2016
7
"5 Amp super-charging" over USB is not a Standard, right?
How exactly did they accomplish that?
I would not what to connect any non-certified ( prototype ) charging circuit to my cell phone.
This was a concern of mine, but if the phone supports up to 5A charging, then surely it would be fine providing it is done correctly?

#### sparky 1

Joined Nov 3, 2018
32
Beside selecting the DC to DC step down converter there are a few automotive electric routines to become familiar with. Like the T connector splits off where the interior dome light is located at the fuse box, because it is live when the key is off.

#### EnJoneer

Joined Oct 11, 2016
7
The manual I have for a Huawei P20 Pro doesn't even mention "supercharging." Has the battery technology advanced to safely do this? And how good is it for the battery in the long run?

And No, EdJoneer, the question is not dumb.
I noticed this when I started looking for specs online, but it was one of the key selling points when I was looking for a new phone - the phone will charge from completely flat in 30-45 mins.
I'm assuming it is safe as it is the standard charger sold by Huawei for this model, and the phone battery has worked perfectly without any noticeable deterioration for several months now, so it seems as though it is fine in the long run. Its a great phone, I am really pleased with it.

#### iONic

Joined Nov 16, 2007
1,650
I was considering buying one of these but had read that some devices have complications working from anything but a pure sine wave inverter?
Also, would it cause any problems to just splice the 12V cable on this and wire it into a 12V system directly?
Thanks for your help!
Have you seen this?
5V/5A 30W Quick Charger