Introduction to BC550, bc550 pinout, bc550 power ratings, bc550 applications, bc550, bc550 equivalents Hi Guys! Happy to see you here. Thank you for viewing this read. In this post today, I’ll walk you through the complete Introduction to BC550. BC550 is a low-power low-frequency general-purpose bipolar transistor. It is mainly used to drive loads under 100mA. BC550 carries three terminals where a s ...