Xiaomi Redmi Note 4X (Snapdragon - Mido) charging current
crok - crok.bic @XDA - crokbic @TelegramTL;DR: no, it won't be beneficial to use a QC3.0 compliant charger,
it won't charge better / quicker your Xiaomi Redmi Note 4X (Snapdragon - Mido)
- But an important and often overlooked item is the chargin cable - use a decent one!
- And temperature: cool down the phone as much as possible because current means heating, heating can cause Li-Poli damage -> hardware in the battery is safeguarding itself -> it will decrease the current to prevent damage.
- And battery level: at low and at high battery percentages the phone (the PM IC and the IC in the battery) will decrease the current for the above mentioned reasons (protecion, that's how Li-Poli battery chargers are working).
Disassembly guide for pics:
http://en.miui.com/thread-554086-1-1.html
PMM8952 Power Management Module
https://developer.qualcomm.com/download/sd600/pmm8920-power-management-module-device-specification.pdf
Chip is limited to 5V and 2A max if everything is ideal
but in real life.. it is never ideal
below 20% and above around 70..75 it is limited (generally speaking).
Around between 30..70% the max (ideally) around 1.5..1.6A in case of the Mido.
Max. was 1.9A if I recall correctly (measured with a USB measurement tool
and depends on the kernel and environmental conditions).
The chip cannot do more than QC2.0+ in this phone.
That is more than QC2.0 but way less than QC3.0,
it's fancy marketing BS name was "USB Fast Charge"
when Mido has been introduced.
This (I mean fast and quick charge functionality)
was a distinguisher function / feature between
budget and mid-range phones of Xiaomi back in 2017.
The chip itself would be able to work at 5V*3A or 9V*2A
but the actual power management chip in the phone
is not able to use 9V, only 5V
(forcefully regulated by the manufacturer,
probably because of heat dissipation, marketing and
licensing to Qualcomm (Xiaomi did not pay for it..))
and not able to go above 2A
and you should consider the thermal dissipation as well,
that's why the chip is going way below 2A, it's heating up..
and thus the PM chip is regulating the current
(max. 1.9A as far as I remember my actual measurement values
and around 1.3A when it's already on charger for about 10..20 mins
(heating up a bit and the battery is between 30..70%)).
Hope this helps - but probably not.
PS: facts are facts, you cannot bend physics nor engineering with software mods.