Hi,
Can someone identify the component marked by the red square in the picture, please? It reads B2, under it is the date code - Y526 (I think).

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Those who know don’t talk. Those who talk don’t know.

I believe it's an NPN transistor configured as the pass transistor in a linear regulator.

I have attached the relevant diagram from the datasheet for the L7250 SMOOTH motor controller. Normally the motor controller generates the Vio supply, but in your case the MCU appears to have its own internal regulation circuitry.

You should be able to determine whether the transistor is NPN or PNP by way of a diode test between the B-E and B-C junctions.

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A backup a day keeps DR away.

I notice that some PCBs use the following transistor at the same location:

2SD2150, Rohm, NPN Low Frequency Transistor, 20V, 3A, 0.2V VCE(sat), marking CF, R = 180-390 hfe:
https://media.digikey.com/pdf/Data%20Sheets/Rohm%20PDFs/2SD2150.pdf

https://www.harddrivesforsale.com/media/catalog/product/cache/1/thumbnail/9df78eab33525d08d6e5fb8d27136e95/7/6/7618cbce-481e-43fe-8371-6cf2bd594361.jpg

_________________
A backup a day keeps DR away.

Thanks fzabkar, now I am digesting the information and looking for a domestic place to buy.

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Those who know don’t talk. Those who talk don’t know.

You don't need to locate the same part. Any number of suitable substitutes exist.

_________________
A backup a day keeps DR away.