This part is a kind of semiconductor called D2578.
Function of this product has 2SD2578.
Manufacturers : Sanyo Semicon Device
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Ordering number:5794 NPN Triple Diffused Planar Silicon Transistor 2SD2578 Color TV Horizontal Deflection Output Applications Features · High speed. · High breakdown voltage (VCBO=1500V). · High reliability (Adoption of HVP process). · Adoption of MBIT process. · On-chip damper diode. Package Dimensions unit:mm 2039D [2SD2578] 3.4 16.0 5.6 3.1 5.0 8.0 21.0 22.0 2.8 2.0 4.0 2.0 20.4 1.0 0.6 2.0 1 2 3 1:Base 2:Collector 3:Emitter SANYO:TO3PML 5.45 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 Symbol VCBO VCEO VEBO IC ICP PC Tc=25˚C Conditions 3.5 5.4 [ ... ]