This part is a kind of semiconductor called 2SC3988.

Function of this product has NPN Triple Diffused Planar Silicon Transistor.

Manufacturers : Sanyo Semicon Device

Image and pinout :

Some of the text within the PDF file :

Ordering number:EN2232B NPN Triple Diffused Planar Silicon Transistor 2SC3988 500V/25A Switching Regulator Applications Features · High breakdown voltage, high reliability. · Fast switching speed. · Wide ASO. · Adoption of MBIT process. Package Dimensions unit:mm 2022A [2SC3988] 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) Base Current Collector Dissipation Junction Temperature Storage Temperature Symbol VCBO VCEO VEBO IC ICP IB PC Tj Tstg Conditions Pulse PW≤300µs, duty cycle≤10% Tc=25˚C Electrical Characteristics at Ta = 25˚C Parameter Symbol Conditions Collector Cutoff Current Emitter Cutoff Current DC Current Gain Gain-Ban [ ... ]

2SC3988 PDF Datasheet Download