This part is a kind of semiconductor called BUZ11A.
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 11 A Not for new design SIPMOS ® Power Transistor • N channel • Enhancement mode • Avalanche-rated Pin 1 G Pin 2 D Pin 3 S Type BUZ 11 A VDS 50 V ID 26 A RDS(on) 0.055 Ω Package TO-220 AB Ordering Code C67078-S1301-A3 Maximum Ratings Parameter Continuous drain current Symbol Values 26 Unit A ID IDpuls 104 TC = 25 °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 30 1.9 mJ ID = 30 A, VDD = 25 V, RGS = 25 Ω L = 15.6 µH, Tj = 25 °C Gate source voltage Power dissipation 14 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 [ ... ]
BUZ11A PDF Datasheet Download
