This part is a kind of semiconductor called D1046.
Function of this product has 2SD1046.
Manufacturers : Sanyo Semicon Device
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Ordering number:ENN677D PNP/NPN Epitaxial Planar Silicon Transistors 2SB816/2SD1046 For LF Power Amplifier, 50W Output Large Power Switching Applications Features · Capable of being mounted easily because of onepoint fixing type plastic molded package (Interchangeable with TO-3). · Wide ASO because of built-in ballast resistance. · Goode dependence of fT on current and good HF characteristic. Package Dimensions unit:mm 2022A [2SB816/2SD1046] 3.5 15.6 14.0 2.6 3.2 4.8 2.0 1.6 2.0 20.0 0.6 1.0 1 0.6 2 3 1.3 1.2 15.0 20.0 ( ) : 2SB816 Specifications Absolute Maximum Ratings at Ta = 25˚C Parameter Collector-to-Base Voltage Collector-to-Emitter Voltage Emitter-to-Base Voltage Collector Current Collector Current (Pulse) Collector Dissipation Junction Temperature Storage Temperature [ ... ]