This document describes the Silicon NPN Triple Diffused Planar Transistor with model number 2SD2390, which is suitable for audio, series regulator, and general purpose applications. The transistor has a collector-base voltage of 160V, a collector-emitter voltage of 150V, an emitter-base voltage of 5V, a collector current of 10A, and a base current of 1A. Its electrical characteristics include a maximum collector leakage current of 100µA, a maximum emitter leakage current of 100µA, a minimum collector-emitter breakdown voltage of 150V, a minimum DC current gain of 5000, a maximum collector-emitter saturation voltage of 2.5V, a maximum base-emitter saturation voltage of 3.0V, a typical transition frequency of 55MHz, and a typical current gain of 95.