This part is a kind of semiconductor called C4351.

Function of this product has 2SC4351.

Manufacturers : NEC

Image and pinout :

Some of the text within the PDF file :

DATA SHEET DARLINGTON POWER TRANSISTOR 2SC4351 NPN SILICON EPITAXIAL TRANSISTOR (DARLINGTON CONNECTION) FOR HIGH-SPEED SWITCHING The 2SC4351 is a high-speed Darlington power transistor. This transistor is ideal for high-precision control such as PWM control for pulse motors or blushless motor of OA and FA equipment. PACKAGE DRAWING (UNIT: mm) FEATURES • Mold package that does not require an insulating board or insulation bushing • On-chip C to B constant voltage diode for surge voltage absorption • On-chip C to E reverse diode • Fast switching speed ABSOLUTE MAXIMUM RATINGS (Ta = 25°C) Parameter Collector to base voltage Collector to emitter voltage Emitter to base voltage Collector current (DC) Collector current (pulse) Base current (DC) Total power dissipation Total power [ ... ]

C4351 PDF Datasheet Download