This part is a kind of semiconductor called MP4021.

Function of this product has Pulse Motor Drive and Inductive Load Switching.

Manufacturers : Toshiba Semiconductor

Image and pinout :

Some of the text within the PDF file :

TOSHIBA Power Transistor Module Silicon NPN Epitaxial Type (Four Darlington Power Transistors in One) MP4021 MP4021 High Power Switching Applications Hammer Drive, Pulse Motor Drive and Inductive Load Switching Industrial Applications Unit: mm • • • • • Small package by full molding (SIP 10 pins) High collector power dissipation (4-device operation) : PT = 4 W (Ta = 25°C) High collector current: IC (DC) = 2 A (max) High DC current gain: hFE = 2000 (min) (VCE = 2 V, IC = 1 A) Zener diode included between collector and base. Maximum Ratings (Ta = 25°C) Characteristics Collector-base voltage Collector-emitter voltage Emitter-base voltage Collector current Continuous base current Collector power dissipation (1-device operation) Collector power dissipation ( [ ... ]

MP4021 PDF Datasheet Download