Can anyone identify this chip on a DAX31MB1AA0 (HP X360 13-AC041TU)

[joshAU]

Hi all.
Motherboard is a DAX31MB1AA0 Rev A.
When this notebook is connected to the USBC charger, this chip quickly gets too hot to touch.
No other signs of life.

Its labelled MS6VD.
I cannot find any datasheets or other information online.
Any ideas as to what it is?

I do not have any schematics or boardviews for this model, however I have just requested them on the schematics forum here.

I have removed the chip and the chip doesn't appear to have any shorts/be connected, to any other pin on it.
With the chip removed, there also seems to be no shorts between any of the pins to any other pin.

The central, "U" shaped pad connects to the ground on the motherboard.
No other pads on the board are connected to ground.

Any suggestions?
Any help/advice greatly appreciated.

[mcplslg123]

Re: Can anyone identify this chip on a DAX31MB1AA0 (HP X360 13-AC041TU)

SY8208BQNC=MS

You can refer to hp Y11A schematic as its used there for details or download a datasheet. Check whether LDO pin is shorted or showing low resistance.

[joshAU]

Re: Can anyone identify this chip on a DAX31MB1AA0 (HP X360 13-AC041TU)

SY8208BQNC=MS

You can refer to hp Y11A schematic as its used there for details or download a datasheet. Check whether LDO pin is shorted or showing low resistance.

Thank you mcplslg123 for the information, and suggestion.
That helps a lot.

With the chip removed, I checked the resistance to the ground pin on pin 5, the 3.3v LDO output, and it is not connected to ground at all.
Even when measuring on the 20MOhm setting.

None of the corresponding pads on the motherboard show a short to ground, other than the ground pad of course.

Pad 5, where the 3.3v LDO would be connected, shows a 180 Ohm resistance to ground.
I have no idea if that is a normal value.

Pad 8 on the board shows 12.57v.
Pad 6 shows a very low and decreasing voltage... i.e. 0.2 volts but rapidly drops.

No other pads show any volts.

[mcplslg123]

Re: Can anyone identify this chip on a DAX31MB1AA0 (HP X360 13-AC041TU)

Pad 5, where the 3.3v LDO would be connected, shows a 180 Ohm resistance to ground-This is not normal. You have some leaky/shorted component on +3V rail. The resistance should be atleast a few Kohms here.

PS: You powered the mb without this IC soldered?? If yes, i'm afraid there may be severe damage to the mb.

[joshAU]

Re: Can anyone identify this chip on a DAX31MB1AA0 (HP X360 13-AC041TU)

Hi again mcplslg123
Thanks again for the advice.

I guess I'll have to look at the +3v rail then... but, unfortunately, I guess, yes, I did power this board without the chip in place.
I did not realise that powering on the board without this chip could cause any further damage?
That's not good...

When I did power it without this chip attached, pad 8 showed 12.57v, which seemed way higher than it should be.

Game over, do you think, or should I continue checking the +3v rail?

[skynetto]

Re: Can anyone identify this chip on a DAX31MB1AA0 (HP X360 13-AC041TU)

PIN 8 is VIN. The component is a step-down regulator which accepts VIN from 4 to 28V.
So is not game over as VIN is within range.

[joshAU]

Re: Can anyone identify this chip on a DAX31MB1AA0 (HP X360 13-AC041TU)

PIN 8 is VIN. The component is a step-down regulator which accepts VIN from 4 to 28V.
So is not game over as VIN is within range.

Hi Skynetto, and thanks for your input.
That's good to hear.
For some reason I thought that pin was meant to be 3.3V.

I found the another regulator, labelled MU3V7, from another, different board, which I assumed is the same specs, but could find no info on it.
I swapped it out.
This one does not heat up at all, unlike the original, that immediately got so hot it hurt.
However, still no sign of life.

[mcplslg123]

Re: Can anyone identify this chip on a DAX31MB1AA0 (HP X360 13-AC041TU)

MU & MS-two different IC. Dont swap an IC without being sure. It can make the whole process unrepairable. You need to first fix resistance being low on pin5 and then solder a new IC. Without solving the low resistance on +3VLDO, it wont give any result and the new IC will also heat up same way .

[joshAU]

Re: Can anyone identify this chip on a DAX31MB1AA0 (HP X360 13-AC041TU)

MU & MS-two different IC. Dont swap an IC without being sure. It can make the whole process unrepairable. You need to first fix resistance being low on pin5 and then solder a new IC. Without solving the low resistance on +3VLDO, it wont give any result and the new IC will also heat up same way .

Thanks again mcplslg123.
I'll remove that IC then.
I couldn't find details, on either chip online, except for your earlier advice on the first chip.
I'll remove it and try to work on the +3VLDO.

[joshAU]

Re: Can anyone identify this chip on a DAX31MB1AA0 (HP X360 13-AC041TU)

Hi again mcplslg123.
I removed the incorrect chip, and retested the 3.3v LDO output.
It is not connected to ground, nor are any other pins connected to ground.
This makes me think its a fault with the chip itself?