Acer Nitro 5 AN517-52-5744 - Not Powering On

[Vesko356]

Re: Acer Nitro 5 AN517-52-5744 - Not Powering On

I injected 1v and did not see anything until I raised it slowly to 2v and then 3v. I found PU301 to heat up quite a lot. What chip is this? I also see pin 2 of this chip is about to break off.

Silergy SY8288BRAC

https://www.badcaps.net/forum/showth...00#post1136600

Page 86

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[mon2]

Re: Acer Nitro 5 AN517-52-5744 - Not Powering On

US $7.92 20%OFF | 10pcs SY8288BRAC SY8288B SY8288 (BAB5ZD BAB5ZD BAB6HA BAB...) QFN-20
https://a.aliexpress.com/_mtKUXnQ

[gnug85]

Hi bialag when you replaced the PU301 IC did this fix your issue ? I have the same problem with the same board. But it looks like pin 1 and 2 are about to come off. and i think there is a crack in my chip. Is this chip BGA or is there a version with pins on the sides ?

[mon2]

PU301 is a QFN package. You can view the exact view of this part using 'QFN 20 package' on google to see the bottom side view. In summary, it is a leadless part with solder pads on its bellyside. You must take a clear pic (as you have done) of the top view so that the replacement can be aligned in the same way. You will need proper tools (hot air soldering; flux tweezers) or work with a local cell phone repair store that can do the same.

Before proceeding, do take measurements of this part of the schematic with a multimeter and sharp probes so they do not short out other pins. The solder joint from the shared pic looks to be ok.

https://itecnotes.com/electrical/ele...package-sizes/

[gnug85]

OK i did measure the voltage on that chip and was not receiving 3V on pin 1. I do have all the tools you mentioned. Anyway the issue with the board won't power up.

[mon2]

Start with the usual dcin mosfets. See the above sticky on charger circuits by piernov.

need to confirm the adapter is ok and then mosfet voltages to ground.