This part is a kind of semiconductor called BUZ20.

Function of this product has SIPMOS Power Transistor (N channel Enhancement mode Avalanche-rated).

Manufacturers : Siemens Semiconductor Group

Image and pinout :

Some of the text within the PDF file :

BUZ 20 SIPMOS ® Power Transistor • N channel • Enhancement mode • Avalanche-rated Pin 1 G Pin 2 D Pin 3 S Type BUZ 20 VDS 100 V ID 13.5 A RDS(on) 0.2 Ω Package TO-220 AB Ordering Code C67078-S1302-A2 Maximum Ratings Parameter Continuous drain current Symbol Values 13.5 Unit A ID IDpuls 54 TC = 28 °C Pulsed drain current TC = 25 °C Avalanche current,limited by Tjmax Avalanche energy,periodic limited by Tjmax Avalanche energy, single pulse IAR EAR EAS 13.5 7.9 mJ ID = 13.5 A, VDD = 25 V, RGS = 25 Ω L = 486 µH, Tj = 25 °C Gate source voltage Power dissipation 59 VGS Ptot ± 20 75 V W TC = 25 °C Operating temperature Storage temperature Thermal resistance, chip case Thermal resistance, chip to ambient DIN humidity category, DIN 40 040 IEC climatic category [ ... ]

BUZ20 PDF Datasheet Download