Introduction to bd137, bd137 pinout, bd137 power ratings, bd137 applications Departments:Electrical EngineeringElectronics EngineeringMechatronics EngineeringComponents:BD137Softwares:Proteus Hi Folks! Hope this finds you well. Thank you for stopping by. In this post today, I'll be discussing the Introduction to BD137. BD137 is an NPN medium power transistor mainly employed ...