View 2sc5243 datasheet:

Power Transistors 2SC5243 Silicon NPN triple diffusion mesa type For horizontal deflection output Unit: mm ? 3.3± 0.2 20.0± 0.5 5.0± 0.3 3.0 Features High breakdown voltage, and high reliability through the use of a glass passivation layer High-speed switching 1.5 Wide area of safe operation (ASO) 1.5 2.0± 0.3 2.7± 0.3 3.0± 0.3 Absolute Maximum Ratings (TC=25?C) 1.0± 0.2 Parameter Symbol Ratings Unit 0.6± 0.2 Collector to base voltage VCBO 1700 V 5.45± 0.3 10.9± 0.5 Collector to emitter voltage VCES 1700 V Emitter to base voltage VEBO 6 V 1:Base Collector current IC 15 A 2:Collector 1 2 3 3:Emitter Peak collector current ICP* 30 A TOP–3L Package Peak base current IBP 10 A Collector power TC=25° C 200 PC W dissipation Ta=25° C 3.5 Junction temperature T