mega555mega face555にする「」「イベ」「データ」「おすすめ」「コミ」をまとめていますのおすすめやのがすぐにわかりますThe 555 is the well known IC in the world. It is one of the most DIY project IC. I created lot of circuits by using 555. Basically it is a cmos timer IC. It contain lot of transistors