This part is a kind of semiconductor called BUZ91A.

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 91 A SIPMOS ® Power Transistor • N channel • Enhancement mode • Avalanche-rated Pin 1 G Pin 2 D Pin 3 S Type BUZ 91 A VDS 600 V ID 8A RDS(on) 0.9 Ω Package TO-220 AB Ordering Code C67078-S1342-A3 Maximum Ratings Parameter Continuous drain current Symbol Values 8 Unit A ID IDpuls 32 TC = 33 °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 8 13 mJ ID = 8 A, VDD = 50 V, RGS = 25 Ω L = 16.3 mH, Tj = 25 °C Gate source voltage Power dissipation 570 VGS Ptot ± 20 150 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, DIN IE [ ... ]

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