This part is a kind of semiconductor called BUL1688.

Function of this product has BUL Series Transistors.

Manufacturers : SI Semiconductors

Image and pinout :

Some of the text within the PDF file :

Shenzhen SI Semiconductors Co., LTD. Product Specification BUL SERIES TRANSISTORS FEATURES APPLICATION: HIGH VOLTAGE CAPABILITY FLUORESCENT LAMP HIGH SPEED SWITCHING ELECTRONIC BALLAST BUL1688 WIDE SOA ELECTRONIC TRANSFORMER Absolute Maximum Ratings PARAMETER Collector-Base Voltage Collector-Emitter Voltage Emitter- Base Voltage Collector Current Total Power Dissipation Junction Temperature Storage Temperature Tc=25°C SYMBOL VCBO VCEO VEBO IC PC Tj Tstg VALUE 700 400 9 5.0 50 150 -65-150 TO-251 UNIT V V V A W °C °C Electronic Characteristics CHARACTERISTICS Collector-Base Cutoff Current Collector-Emitter Cutoff Current Collector-Emitter Voltage Emitter-Base Voltage Tc=25°C SYMBOL ICBO ICEO TEST CONDITION Collector-Emitter Saturation Voltage Base-Emitter Saturation Voltage DC [ ... ]

BUL1688 PDF Datasheet Download