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I suspect this is a diode: the board has PD13 marking next to it. I found a schematic for a similar product that identifies the PD13 as TVS_SMAJ20A. Would that make it a TVS diode?

the cracked part

another picture of the part

third view

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    \$\begingroup\$ I’d say it was a TVS. It seems there was enough fault current to destroy it so there’s other collateral damage methinks. You can replace the diode, but it is not needed for the circuit to function. \$\endgroup\$
    – Kartman
    Dec 9, 2021 at 4:10
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    \$\begingroup\$ Looking at how large the copper pours at the anode and cathode are, I wouldn't be surprised if they have used the diode as a reverse polarity protection. \$\endgroup\$ Dec 9, 2021 at 7:22
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    \$\begingroup\$ If it's a TVS which seems likely, the part was perhaps destroyed since it is mounted backwards. It would conduct all the time. TVS tend to short whenever they go poof. \$\endgroup\$
    – Lundin
    Dec 9, 2021 at 9:13

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PD13 is a designator it doesn't really tell you the part number or the part characteristics. It probably stands for "protection diode" or something like that, and it's the 13th in some kind of ordering.

You need the second character in the code to be sure. It's plausible that's what it is, because the SMAJ20A (which is a part number) has the code BV. Since it has the lines on one end it's unipolar type. From the datasheet

enter image description here

Caution though- there are maybe 10 part numbers that have a code starting with 'B' so the ID hinges on how 'similar' your similar product is. Since it has the same designator I'd guess it's very close...

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    \$\begingroup\$ I would say that TVS is the most likely too, although in that case it is mounted backwards. Alternatively it could be a series diode for polarity protection and then it can be pretty much any part, likely a Schottky. \$\endgroup\$
    – Lundin
    Dec 9, 2021 at 9:15

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