ACER Notebook Spin 7

[mferna14]

Hi all, need help in repairing this notebook. Any help across the world will be greatly appreciated. I am working on ACER Notebook Spin 7 Model SP714-51-M5H3 logic board. The notebook is working fine but only problem is the battery does not charge. The battery is brand new. On the first instance one of the Battery charge MOSFET blew out. I replaced it & started to get voltages on the battery terminals of the main logic board. But this voltage is 18.5 voltage not the regular 11~12volts & when I plug in the new battery the Mosfet turns hot. Then I replaced with original MOSFET (A5 GNE) & checked the other mosfet (AON7410), they were all good but no difference with the voltage still 18~19volts DC. Checked the Schematics (Acer VN7-592G Rayleigh 15292-1) & the charging chip BQ24780S. I noticed on Pin 27 ("Phase" PWR_CHG PH) its generating 18.5V whereas the voltage on this pin should be 11.5 ~13V. Then I replaced this chip with a brand new, NO LUCK., voltage is not getting under 18v. Checked all the components nearby, all diode & resistors seem to be ok. Any help or tips to repair this board will be greatly appreciated. Thanks in advance

[piernov]

Re: ACER Notebook Spin 7

Replace the high-side MOSFET that feeds the battery charging rail from B+

[mcplslg123]

Re: ACER Notebook Spin 7

yes, agree with piernov.

[mferna14]

Re: ACER Notebook Spin 7

PIERNOV., Thank you so much for the reply & understanding my problem... Can you pls. guide what do you mean by "replace the high-side MOSFET" or what is "high-side", appreciate your help

[mferna14]

Re: ACER Notebook Spin 7

mcplslg123... thanks buddy, which will be the"HIGH-SIDE" MOSFET

[mferna14]

Re: ACER Notebook Spin 7


Hope I have attached the Schematics right., can you pls. identify me the MOSEF to check or replace on page 37 & Page 38, I would appreciate

[on/off]

Re: ACER Notebook Spin 7

I believe what Piernov means is PU4404.

BTW thanks for schematic.

[mcplslg123]

Re: ACER Notebook Spin 7

mcplslg123... thanks buddy, which will be the"HIGH-SIDE" MOSFET

Yes PU4404 is your high-side mosfet

[mferna14]

Re: ACER Notebook Spin 7

Thanks., PU4404 this is the first MOSFET I checked & even replaced with original one., but still can't get the voltages lowered, still 18volts on the source whereas this volt on the source should be 12volt... any other tip will be greatly appreciated.

[brew99]

Re: ACER Notebook Spin 7

Take another good look at your charger IC (BQ24780S) and make sure pins 26/27 not shorted together. Maybe try replacing that again. There isn't many places the 18V can be coming from if you are sure that the high side FET is good.

[piernov]

Re: ACER Notebook Spin 7

Check PU4402 as well.
If it's not PU4402, replace charger IC and PU4404 at the same time, making sure charger IC is sitting flat on the board without solder bridges.

[mferna14]

Re: ACER Notebook Spin 7

Thanks for all your replies. I checked the pin 26/27 & they are not short., checked under the microscope to see if I did not solder the chip right but all is fine.. Did a good ultra sonic cleaning to the chip & nearby components. This seriously has become a challenge for me.. Check the photo pls. of the replaced MOSFET & the location where I am checking & troubleshooting., & if one observes the inductor PL4401., it was draining so much amps when I installed the brand new battery that it became very hot & lost its color. But this was happening before with the old battery too, this is why the old battery does not give out any voltage on any of its battery terminal pins.. & if one observes the schematics, I see that pic of PU4402 is a PNP FET & when I actually check the PDF of this FET TPCC8103-GP, it clearly is a NPN channel. On the Gate & Source of this FET PU4402 I get 19Volts & on drain I should be getting around 12volts, whereas this is 19v too. So confusing!!!

[brew99]

Re: ACER Notebook Spin 7

The TPC8103 shows a P-channel when I looked it up, so matches the sch. The other charging FETS (HI/LOW) are N-ch.

https://www.digikey.ca/product-detai...-CT-ND/2310694

Have you replaced PU4402?

I had a similar issue where the battery wouldn't charge, but it would work with either battery or AC, and it ended up being the BQ24780S charging IC. I swore it was soldered correctly and even measured out the same to a known good board (diode mode). I eventually replaced the IC again and it worked.

[mferna14]

Re: ACER Notebook Spin 7

No, not replaced PU4402 as it shows good, I replaced the chip before too., but first I will replace the FET PU4402., maybe it shows good & there might be some internal switching problems. So you are saying that this is P-Channel MOSFET as per the schematics & as per the link you send. If so, then here lies the problem, MFG Have used AON7410 x 2 & the high side MOSFET is A5 GNE, all 3 N-Channel FETs. But this NB was untouched, only I did all the soldering & replaced parts. Let me try.

[brew99]

Re: ACER Notebook Spin 7

I think the schematic you have is incorrect, or not the right one for your MB.

As per the BQ24780S pdf, the FETs are suppose to be N-ch. (1st page of attachment), including the BATFET (PU4402 in your case). All the FETs you have on the MB are N-ch as you have found out

I would still be looking at the PU4402, and also the BQ chip.

[mferna14]

Re: ACER Notebook Spin 7

brew99., you are great & very helpful.... thank you buddy.. today I was bored enough to work on this motherboard again as I had others to look into. Tomorrow first thing in the morning I will go through the chip's PDF file & see what wrong am I doing... So you are saying to go with the BQ24870S schematics pdf to figure out the problem. "Brew99" I will run through the Application information of this chip's pdf 8.1 & 8.2 to see where am I wrong... Yes I think I have got the wrong schematics.. Does anyone have the right schematic for this motherboard ACER Spin 7 VN7-592G Rayleigh SLS 32bit 15292-1 ??? Thanks to all who are helping me out & figure out the problem...

[mferna14]

Re: ACER Notebook Spin 7

Good morning., I replaced all the N-Channel MOSFETs & even the BQ24780s chip but still no luck... Still generating 18v., it works fine with the battery & I notice that when on battery the FETs turn a bit hot, but when I plug in the original ACER power adapter, it burning hot. Any more tips will be greatly appreciated., I need to repair this, its become a challenge now... hope we all come up with a solution. Help me please.... Thanks

[zhang]

Re: ACER Notebook Spin 7

try to remove pu4402 and try with adaptor
does it still have 19v in drain?
if it still remain the same, remove PL4401 and check the voltage on pr4417 ( on adaptor )

[zhang]

Re: ACER Notebook Spin 7

I think the schematic you have is incorrect, or not the right one for your MB.

As per the BQ24780S pdf, the FETs are suppose to be N-ch. (1st page of attachment), including the BATFET (PU4402 in your case). All the FETs you have on the MB are N-ch as you have found out

I would still be looking at the PU4402, and also the BQ chip.

as for the schematic, I think it is correct, although from datasheet shows that adaptor fet and bat fet should be N-channel, but the function has been converted through pq4401? "just deduction"

[shibu]

Re: ACER Notebook Spin 7

hi, please check the connection between pu4401 drain to pu4402 gate both fet's are p channel as per the diagram