Can anyone tell me which U2 IC(charging ic) will support my at&t iphone 5s

Hi everyone,

I purchased my iphone 5s in between july to august 2014 recently I went to a tour where I used to charge it with portable charger which resulted in dead U2 IC(charging ic) as I was out of country I get it repaired with a local guy which brought it to life but now my phone heats up a bit and battery back up is only 10 hours on stand by 😟. I read on net that it might be because my board is not supporting new U2 IC.

I am now planning to replace U2 IC myself as I have all tools available and have repaired my old phones.

Can anyone tell me how to know which U2 IC(Charging IC) will support my at&t iPhone 5s.

Thanks