help needed with BQ24737 ACOK

[rookieme]

Hello,
I have a dell that fails to charge batteries.
The charger circuit is BQ24737 [the schematic shows different part, also I could only find a datasheet of BQ24735].
I could narrow my search at the fact that ACOK is 0V [the pull up resistor PR4434 is ok and gets the 3D3V_AUX_S5].
ACDET is 2,44V
VCC is 19,55V
SRN is 2,6V [without battery]


datasheet says:
voltage on VCC is 275 mV above voltage on SRN pin, indicating a valid adapter is present to start charge
but this makes no sense as VCC is much above the battery voltage.

what am I missing?

[ktmmotocross]

Re: help needed with BQ24737 ACOK

It is not 735

For me it looks like 707

https://cdn.badcaps-static.com/pdfs/...107dc7e515.pdf

[meritosari]

Re: help needed with BQ24737 ACOK

ktmmotocross was right, ACOK should be LOW, because the signal should not trigger PWR_CHG_ACOK to pulling down to GND.

[smali]

Re: help needed with BQ24737 ACOK

you should check the resistor PR4416? is it OK?

[rookieme]

Re: help needed with BQ24737 ACOK

the PU4404 is marked clear with BQ737

PR4416 has been measured ok - I have never seen one fail as it's a load resistor

[raajkumar]

Re: help needed with BQ24737 ACOK

Your attached schematic shows on page 98 & 97 are BQ24717 and BQ24715. But both are same. In my experience I Replaced for BQ24736 by BQ24725. It is working on a HP Probook 450 G2 Laptop.

[rookieme]

Re: help needed with BQ24737 ACOK

also noticed at page 43 close to down right corner mentions BQ24707

so what is the correct charger ic for this?
am I having charging issue from that ic?

[raajkumar]

Re: help needed with BQ24737 ACOK

also noticed at page 43 close to down right corner mentions BQ24707

so what is the correct charger ic for this?
am I having charging issue from that ic?

BQ24707 also same Data on all pin so no problem if you want to replace it you can use 707, 717, 715, 725, 735, 736, 737 also same pin arrangement.

[ktmmotocross]

Re: help needed with BQ24737 ACOK

r u kidding right?

[meritosari]

Re: help needed with BQ24737 ACOK

BQ24707 also same Data on all pin so no problem if you want to replace it you can use 707, 717, 715, 725, 735, 736, 737 also same pin arrangement.

AFAIK:
BQ707, BQ727 need ACOK LOW
BQ725, BQ735 need ACOK HIGH

Check datasheet again!

And a few different the pin out also I think New of the IC only for support Turbo Boost Mode.

[raajkumar]

Re: help needed with BQ24737 ACOK

Yes you are correct. I used the datasheet to check pinout for BQ735 to BQ725 it is working without any problem. Actually i didn't check for BQ707, 717, 715. I checked for 725, 735 only its using 1 to 4 cell batteries.

[ktmmotocross]

Re: help needed with BQ24737 ACOK

707 and 735 cannot be interchanged.

[rookieme]

Re: help needed with BQ24737 ACOK

So in my case could somebody replaced 707 with 735 before?
The 707 seems the correct one?

[ktmmotocross]

Re: help needed with BQ24737 ACOK

maybe u post wrong schematic

[meritosari]

Re: help needed with BQ24737 ACOK

http://notebook1.ru/forma1/viewtopic...767636#p767636
https://drive.google.com/open?id=0Bz...WNGSmtxalJKY3M

[rookieme]

Re: help needed with BQ24737 ACOK

that picture confirms that the 737 is the correct one

[JLCurve]

Re: help needed with BQ24737 ACOK

Hi!
Did you successfully replace the 24737 for a 24707 (available at DK)?

I also have a board (NM-A032) that has a 24737 charger that does not seem to want to do anything. All voltages seem fine, including the 6V ldo output but it does not start charging.

The board had a shorted capacitor on VIN ..

Thanks,
Joseph.

[hrfam]

Re: help needed with BQ24737 ACOK

hi ....test gate on p1 &p2 mosfet ...if have 19v acprn is missing //check acprn {acok} block under schematic page

[Faijul Hasan]

Re: help needed with BQ24737 ACOK

any one give me bq24736 datasheet

[Sametbey]

Re: help needed with BQ24737 ACOK

Especially for the Dell notebook, the adapter is important. original adapter (contains the thin pin adapter information of the adapter socket). Without the proper adapter, charging may not start. similar charging circuit. The 737 to 735 ACDRV differ.