This part is a kind of semiconductor called 3DD1555.

Function of this product has CASE-RATED BIPOLAR TRANSISTOR.

Manufacturers : JILIN SINO

Image and pinout :

Some of the text within the PDF file :

CASE-RATED BIPOLAR TRANSISTOR FOR TYPE 3DD1555 FOR LOW FREQUENCY R 3DD1555 MAIN CHARACTERISTICS BVCBO IC VCE(sat) tf 1500 V 5A 5 V(max) 1 s(max) Package TO-3P(H)IS APPLICATIONS z z Horizontal deflection output for color TV. FEATURES z3DD1555 NPN z 3DD1555 is high breakdown voltage of NPN bipolar transistor. The main process of manufacture: high voltage mesa type process, , triple diffused process etc., adoption of fully plastic packge. RoHS RoHS product. ORDER MESSAGE 123 EQUIVALENT CIRCUIT RBE=50 (Typ.) Order codes Marking Halogen Free Package 3DD1555-O-A-N-D D1555 NO TO-3P(H)IS MARKING Packaging Foam Device Weight 5.50 g(typ) Trademark Part No. Year month For example 8 2008 10 10 october 200911D 1/6 R ABSOLUTE RATINGS (Tc=25 ) 3DD1555 Parameter Collecto [ ... ]

3DD1555 PDF Datasheet Download