This part is a kind of semiconductor called 2SC4977.
Function of this product has Silicon NPN Power Transistor.
Manufacturers : INCHANGE
Image and pinout :

Some of the text within the PDF file :
INCHANGE Semiconductor isc Product Specification isc Silicon NPN Power Transistor 2SC4977 DESCRIPTION ·Collector-Emitter Sustaining Voltage: VCEO(SUS)= 400V(Min) ·Fast Switching Speed ·Collector-Emitter Saturation Voltage: VCE(sat)= 0.8V(Max.)@ IC= 4.0A APPLICATIONS ·Designed for use in high-voltage, high-speed , power switching in inductive circuit , they are particularly suited for 115 and 220V switchmode applications such as switching regulator’s, inverters, DC-DC converter. ABSOLUTE MAXIMUM RATINGS(Ta=25℃) SYMBOL VCBO VCEO VEBO IC ICM IB PC TJ Tstg PARAMETER Collector-Base Voltage Collector-Emitter Voltage Emitter-Base Voltage Collector Current-Continuous Collector Current-Peak Base Current-Continuous Collector Power Dissipation @ TC=25℃ Junction Temperature Storage Tempe [ ... ]
2SC4977 PDF Datasheet Download
