Help identifying chip

[Jordanaudio]

Definitely a beginner with a lot to Learn. I’ve got a Dell D6000 Dock that is shutting down the charger which I take to mean a short somewhere.  I saw on my thermal camera this chip getting hot quickly before the charger shuts down.  I believe this chip to be a MOFSET. I have searched for EMA2182 datasheet and come up dry.

Charger no longer shuts down with this chip off the board. With DMM in diode mode, red on the pad/pins 5-8 and black on 1-4 in order I read 0.481 V, for 1-3 and open for 4.  Then I go back to pin 1 and the readings are 0.002V for pins 1-3. With black on pins 5-8 it’s open.

Resistance measures black on 5-8, red OL on 1-4. Red on 5-8 black on 1-3, 9.2 Mohm, 4 OL. Then 1-3 measure 1.6 Ohm. 

This seems like 4 is a gate being opened to ground?

Is there an equivalent replacement for this chip?

Thanks for your help!

[aliarifat794]

Maybe it's a custom-made chip.

[Ranayna]

Looks like this one or very similar:
https://alltransistors.com/adv/pdfview.php?doc=emb09p03v.pdf&dire=_1

B09P03 was my searchterm.

Edit: clarified link

[Jordanaudio]

I’m willing and trying to learn. I’m fairly confident in that I don’t know enough to even know what I don’t know, if that makes sense. But all of my various “can I fix it?” electronics projects are “nothing to lose” propositions.  The devices would just get thrown out anyway.   

With no schematics available that I can find, should I consider the possibility that this chip is doing what it’s supposed to do, opening to ground? Is that a thing?  That would mean the short would be somewhere else after this chip. I’m willing to keep probing with the DMM but I’ll be doing so blindly.

[Jordanaudio]

That’s interesting and begs the question, which may already be answered somewhere in this forum so apologies if it has, how do you know which of the numbers to search? I’ve struggled in the past with this issue on these “larger” chips that have multiple lines of text

[Ranayna]

That’s interesting and begs the question, which may already be answered somewhere in this forum so apologies if it has, how do you know which of the numbers to search? I’ve struggled in the past with this issue on these “larger” chips that have multiple lines of text

In this case, it was easy. You already tried the lower line of text and found nothing.
That this is very likely a MOSFET, as you said, is obvious due to the layout.

So my google term was "mosfet b09" and at that point google already suggested b09a03 and b09n03. Both find MOSFETs very similar to yours, including packaging and manufacturer logo, so it is easy to deduce that "p03" is a relevant part of the partnumber.

[MarkT]

Looks like its EMB09P03V p-channel power mosfet, 30V, 9.5 milliohm.  https://alltransistors.com/mosfet/transistor.php?transistor=49933