This part is a kind of semiconductor called BU2527DX.
Function of this product has Silicon Diffused Power Transistor.
Manufacturers : NXP
Image and pinout :

Some of the text within the PDF file :
Philips Semiconductors Product specification Silicon Diffused Power Transistor BU2527DX GENERAL DESCRIPTION New generation, high-voltage, high-speed switching npn transistor with integrated damper diode in a plastic full-pack envelope intended for use in horizontal deflection circuits of high resolution monitors. Features improved RBSOA performance. QUICK REFERENCE DATA SYMBOL VCESM VCEO IC ICM Ptot VCEsat ICsat ts PARAMETER Collector-emitter voltage peak value Collector-emitter voltage (open base) Collector current (DC) Collector current peak value Total power dissipation Collector-emitter saturation voltage Collector saturation current Storage time CONDITIONS VBE = 0 V TYP. 6.0 1.7 MAX. 1500 800 12 30 45 5.0 2.0 UNIT V V A A W V A µs Ths ≤ 25 ˚C IC = 8.0 A; IB = 1.6 A f = 64 kH [ ... ]
BU2527DX PDF Datasheet Download
