Please Help me to identify this component.

[AdrianM55]

Hello
Does anyone recognises this component? (Goes up to 140 degrees C)



It's a u3 but don't know if it's 1N5EF or IN5EF either doesn't exist on the internet.

[antonis]

Judging from pins number, I vote for a voltage-current regulator..
(something like L200 or so..)

[Rob Strand]

It's one of those "modern" day regulators for sure.

At first the inductor and cap made me thing ik was a switch-mode.

This one is likely.  Many variants.  5EF marking = UM37519S = 1.9V
http://www.union-ic.com/Upload/Datasheet/Datasheet_UM375xx_Rev07.pdf

If it's hot you could have a short, eg. shorted tantalum cap.  It could also be the device is fried
but my first bet goes with a fault elsewhere.

[bluelagoon]

My Gues is it to be something like a    SOT23-5
IC REG LINEAR 5V
something akin to
https://www.digikey.com.au/en/products/detail/diodes-incorporated/AP2204K-5-0TRG1/4470810
Good luck with the final analysis.

[AdrianM55]

It's one of those "modern" day regulators for sure.

At first the inductor and cap made me thing ik was a switch-mode.

This one is likely.  Many variants.  5EF marking = UM37519S = 1.9V
http://www.union-ic.com/Upload/Datasheet/Datasheet_UM375xx_Rev07.pdf

If it's hot you could have a short, eg. shorted tantalum cap.  It could also be the device is fried
but my first bet goes with a fault elsewhere.

Oh yeah it's roasting! Temp goes up to 140C.
I'll check where the Via goes and will try to locate the short if that's the case.

It happens to have audible fx after 5-10 secs. So at first I thought it might be the caps on the bottom side of the board (these are the small explosive SMD cans). Checked the voltage and it's around 14v and after the chip gets hot voltage starts to fluctuate between 11~14v.

[Rob Strand]

Checked the voltage and it's around 14v and after the chip gets hot voltage starts to fluctuate between 11~14v.

If it's 14V out, that seems too high for a 1.9V regulator.  It's possible the regulator is misbehaving and the 14V into a 1.9V circuit is simply pulling a lot of current.

It would be worthwhile tracing the circuit around the regulator to make sure all the pin assignments in the datasheet
match up with actual circuit eg. Vin, Vout, Gnd all makes sense.    There a small chance it is another chip, although likely to be something similar.

R35 and R38 go to the shut down pin and it's not clear why those resistors are present.  It could be something do to with the regulator being shut down by a microprocessor and the resistors a related to that.

[AdrianM55]

Came out to be that these can be a culprit (Q6,Q8) as there is something not right with relays and as someone stated if these are bad it might be drawing current as they're driving relays.

Problem is not only accessibility but once again I can't tell what these are. I seen them in other electronics but don't remember.

Thank you for clues we're getting somewhere.

[Rob Strand]

Problem is not only accessibility but once again I can't tell what these are. I seen them in other electronics but don't remember.

Thank you for clues we're getting somewhere.

From what I can see from the part designator, package and PCB connections it's likely to be a dual MOSFET.
Probably plain "dual" with two of the same devices in the one package as opposed to a dual complementary MOSFET.

Not sure of the package but it's probably TSOP-363 (or SOT-363).

The TWP marking didn't come-up with anything, although it could be TW or WP.

That would make sense if the devices are driving relays.  That being the case I suspect each MOSFET in the package is wired as an inverting switch with grounded a source.  One device feeds into the next where the first device is used as an inverter.   The R60 resistor is the pull-up resistor for the gate of the second MOSFET.  Then the second device drives a relay.   The configuration could be used to drive anything, even LEDs.

This is a place holder for further research.  Maybe not this one but something close.

WP marking

Infineon, BCR22PN

https://www.infineon.com/dgdl/bcr22pn.pdf?folderId=db3a30431428a37301144053a52002e2&fileId=db3a30431428a3730114406a036a02fe