This part is a kind of semiconductor called 150N03.
Function of this product has N-Channel Enhancement Mode Field Effect Transistor.
Manufacturers : Cmos
Image and pinout :

Some of the text within the PDF file :
CMP150N03/CMB150N03/CMI150N03 N-Channel Enhancement Mode Field Effect Transistor General Description Product Summery The 150N03 is N-ch MOSFETs with extreme high cell density , which provide excellent RDSON and gate charge for most of the synchronous buck converter applications. Features Simple Drive Requirement Fast Switching Low On-Resistance Absolute Maximum Ratings G DS TO-220 (CMP150N03) BVDSS 30V RDSON 4.5m ID 120A Applications HIGH CURRENT, HIGH SPEED SWITCHING DC-DC & DC-AC CONVERTERS MOTOR CONTROL, AUDIO AMPLIFIERS SOLENOID AND RELAY DRIVERS AUTOMOTIVE ENVIRONMENT TO220 / TO263 / TO262 Pin Configuration GD S TO-263 (CMB150N03) G DS TO-262 (CMI150N03) Symbol VDS VGS ID@TC=25 IDM EAS PD TSTG TJ Parameter Drain-Source Voltage Gate-Sou ce Voltage Continuous Drain Curren [ ... ]
150N03 PDF Datasheet Download
