Laptop battery charging circuit

[fauzanmint]

Re: Laptop battery charging circuit

Thank You

[FaissalDZ]

Re: Laptop battery charging circuit

Very helpful information, thanks

[lazaro.089]

Re: Laptop battery charging circuit

Thank you @Piernov!

I have a question. I have 2 identical laptops (HP Pavilion Gaming Laptop 15-dk011la)

1 does charge the other doesn't. Both batteries charge in one laptop. Both adapters are recognized in both laptops.

But one of them refuses to charge the battery. What should I check first?. The battery is detected correctly in the laptop that doesn't charge (powercfg /batteryreport OK). It discharges just fine. But charging doesn't work.

Aný ideas?

[Cuboy]

Re: Laptop battery charging circuit

Thank you for the post.

[antunes.jrca]

Re: Laptop battery charging circuit

Thanks for this very good topic.

[emirich]

Re: Laptop battery charging circuit

Thanks

[fabio fanesi]

Re: Laptop battery charging circuit

Thank you so much for the precious informations!!

[Weelcup]

Re: Laptop battery charging circuit

Thanks a lot

[lappyfixer]

Re: Laptop battery charging circuit

thank you for the detailed post piernov, exactly what ive been searching for...

[Gomez2969]

Re: Laptop battery charging circuit

Thanks so mush

[piernov]

Re: Laptop battery charging circuit

Yes indeed, some platforms only have the AC adapter connected to the DCIN/VCC pin of charger IC, and others have the DCIN/VCC pin of the charger IC connected to both battery and AC adapter (through a dual diode).
I don't have a definitive explanation about it.
It makes sense to have the battery connected to it if you still use some features of the charger IC like current sensing on battery only, but at the same time some platforms provide these features on battery only even though the DCIN/VCC pin is not connected to the battery. So I assume they take the power internally from the battery rail.

[Greg81]

Re: Laptop battery charging circuit

Hello,

I have a question to the following:

DCIN/VCC: input voltage from the AC adapter, should be close to AC adapter voltage

Does the input voltage always come from the AC Adapter? Is the charger IC inactive when running from battery? I was trying to understand the input voltage for Quanta FH5 mainboard, there seems to be no connection to the battery rail although in every IC charger datasheet you read about input from battery and in other schematics VCC is connected to the battery input.

[dhan]

Re: Laptop battery charging circuit

Thank You for this informative thread

[DavidThijs]

Re: Laptop battery charging circuit

I have a question for a problem with the two n-channel mosfets - which I already replaced to be on the safe side. The BQ24725 emits every 1.3 seconds a very short pulse with an amplitude of approx 11v on the gates of the two N channel mosfets. When does the charge controller go in such a mode ? On battery alone, the mainboard correctly powers up. On the DC jack alone, I get nothing unless I bridge the 1st mosfet. Then the power button starts the laptop. Having both battery and a lab power supply connected to the DC jack won't start the laptop unless I bridge again the 1st mosfet. But then the current limiter of the lab psu kicks in for good reasons. Any ideas would be appreciated.

[kalilinux25]

Re: Laptop battery charging circuit

new ideas noted keep sharing

[stingerchamp]

Re: Laptop battery charging circuit

Hello, good morning thanks for accepting me I have a question
It had a board in which there was no scheme but its input mosfets were channel N, the charger source was the Bq25a, therefore the charger activated the gates to the mosfets, however, in the gates of the mosfets there was no voltage, now the charge ic was powered it had the acdet = 2.41, the acin was 0v and the regn = 0v but the capacitor that goes in that Regn line was beeping on both sides, I took the capacitor to measure outside and it was fine to feed the plate without that capacitor and in the regn terminal had no voltage, my query is, could the ic charger be bad?
I also took out the second mosfet to measure it outside and it's ok, thanks

If charging ic is not generating REGN and charging ic vcc is ok and acdet is normal then yes you are right otherwise check logic and signal state Active on low or high

If you read sheet there you will find comparing circuit read it for more information

[kadi144]

Re: Laptop battery charging circuit

thamks

[jessy]

Re: Laptop battery charging circuit

Hello, good morning thanks for accepting me I have a question
It had a board in which there was no scheme but its input mosfets were channel N, the charger source was the Bq25a, therefore the charger activated the gates to the mosfets, however, in the gates of the mosfets there was no voltage, now the charge ic was powered it had the acdet = 2.41, the acin was 0v and the regn = 0v but the capacitor that goes in that Regn line was beeping on both sides, I took the capacitor to measure outside and it was fine to feed the plate without that capacitor and in the regn terminal had no voltage, my query is, could the ic charger be bad?
I also took out the second mosfet to measure it outside and it's ok, thanks

[ruletero]

Re: Laptop battery charging circuit

Thank you for the information, is very usefull.

Now, in case of battery not detected and not short in SMBUS SDA and SCL lines, what other thing can cause the fail?

[nassih]

Re: Laptop battery charging circuit

very important topic tanks