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.
- Attachments
-

-
