How to find maximum input voltage and maximum input current supported by an android phone?

[smarty3010]

Hello,
Is there a way to know maximum input voltage and maximum input current supported by an android phone?

As an example, If the output voltage of a charger is 9V but the android phone supports only maximum of 5V input voltage then this would damage the battery.

If the output current of a charger is more than the maximum input current supported by the android phone then this would not damage the battery but knowing the maximum input current supported will help to buy a charger having the output current equal to or more than the maximum input current supported so that the phone can be charged as fast as possible.

(Please correct me if I am wrong in any of the above statements)

Thank you.

 

[AugieTN]

I'm a little confused on what you are asking. As far as I know all phones input voltage is 5 volts. There may be a couple of phones, like a satellite phone or radio phone that have a different input voltage

Maximum input current is normally listed in the specs. GSMarena normally has the specs for the battery. Here's an example. The Pixel 7 battery is rated at 20 watts
Google Pixel 7 - Full phone specifications
It won't hurt the battery to use a 30 watt charger when the battery is rated at 20 watts

Did that answer what you are asking?

 

[Fox Mulder]

9V is used for fast charging on capable devices. A fast charge adapter will usually be able to provide either 5V for standard charging or 9V for fast charging depending on what the device can accept and how it is set. Most likely you won't damage a non-fast-charging phone by plugging it into a fast-charge adapter but it's best to check the specs first.
We don't know what phone you have but on my Samsung, under Settings/About Phone/Status there is an item "Rated" which shows DC 9V 1.67A and that indicates it's capable of fast charging.

 

[AugieTN]

Thanks for posting that @Fox Mulder

I found something interesting in PCMag

.....Most phones and other devices are capable of handling 5V/2.4A. For fast charging, manufacturers bump the voltage up from 5V to 9V or 12V and beyond, or increase amperage to 3A and above. The introduction of USB-C helps accomplish this with support for up to 100W and 20V, which makes faster charging speeds possible....

What Is Fast Charging?

 

[smarty3010]

Thank you AugieTN and Fox Mulder for your replies.

1. Power (W) = Voltage (V) * Current (A). Knowing the maximum input power (watts) supported, one cannot know the maximum input voltage supported. The example given by Fox Mulder is where the charger has options of 9V or 5V output [Image attached] , so maybe you can use the term "backwards compatible" for such chargers where the charger will be automatically set to 5V output for phones which support only 5V input charging. But, as an example, if the charger has ONLY 9V or 12V or 20V output and the android phone has ONLY 5V input charging supported then this will damage the battery.

2. [Ways to know maximum input power/voltage/current supported] I have two phones currently. First, Realme Narzo 30 Pro 5G: Realme Narzo 30 Pro 5G - Full phone specifications where 30W is stated. Some similar sites have also stated that maximum input power is 30W. I have the original charger which has output: "5V * 2A or 5V * 6A Max" so fastest charging (5V * 6A = 30W) is possible and hence I also know that at least 5V input voltage is supported. But whether higher voltages are supported, that I don't know. Second phone I have is Samsung Galaxy On8 (quite an old phone): Samsung Galaxy On8 - Full phone specifications where maximum input power/voltage/current supported is NOT stated. I have also checked specs for Samsung Galaxy On8 in other sites but maximum input power/voltage/current supported is again NOT stated. Also I don't have the original charger. In both the phones I can't find the maximum power/voltage/current supported in any Android Settings, Battery apps, Device Info apps etc. Hence for the second phone (Samsung Galaxy On8), I can't find a way to know the maximum input power/voltage/current supported!!

@Fox Mulder: Which Android Version are you using on your Samsung phone?

Thank you.

 

[Dannydet]

Well if you knew all that, why did you ask in the first place?

 

[smarty3010]

@Dannydet
I was only aware of chargers having options of 9V or 5V output. I didn't knew that a charger having options of 9V or 5V output would automatically set to 5V output for phones supporting only 5V input charging. I have implied that from Fox Mulder's reply "A fast charge adapter will usually be able to provide either 5V for standard charging or 9V for fast charging depending on what the device can accept and how it is set. Most likely you won't damage a non-fast-charging phone by plugging it into a fast-charge adapter". Again someone can correct me if it is wrong. (Extremely sorry, I should have written in my previous post that I am implying from... and correct me if wrong)

I also didn't knew that some websites like GSMarena would provide information for maximum input power. I came to know that from AugieTN's reply "GSMarena normally has the specs for the battery ...."

I also didn't knew that there are chargers with 12V or 20V or higher. I came to know from AugieTN's reply "...For fast charging, manufacturers bump the voltage up from 5V to 9V or 12V and beyond, or increase amperage to 3A and above. The introduction of USB-C helps accomplish this with support for up to 100W and 20V..."

(hence word added in my previous post by editing it)

I have merely summarized the information 'we' have all posted here in the first and second point of my reply for convenience of all readers. At the same time, I am still asking questions like whether one can know the maximum input power/voltage/current supported from any Android Settings (depending on Android Version), from any Android apps available on Play Store or in any other way. Someone with knowledge of the chargers presently available can post here whether chargers having output: 12V or 20V etc also have 5V output to support phones having only 5V input charging etc etc...

 

[Hadron]

I don't think I'd bother checking precise voltage+current combinations. What's important is what charging standard(s) the phone supports. So for example my phone supports USB-PD up to 25W. In practice this means that any USB-PD charger should work with it. In fact three of my four PD chargers are rated higher than 25W, two of them substantially higher, but that's not a problem as the phone controls how much power is delivered. So basically "what standard does the phone use?" "what power does it accept?" and find a charger that ticks both boxes. Job done.

The more important question is "do I trust the manufacturer to have implemented the standard correctly and built the charger to a decent quality?". My PD chargers are 2 Ankers, an Apple Macbook Pro power adapter and the charger from my old Pixel 2, so the answer for each of those is "yes". But if I found some supposed high-power PD charger on Alibaba or eBay for a fraction of the price of the Ankers I'd most definitely not touch it, regardless of what specifications it claimed.