Introduction to 1n4004, 1n4004 pinout, 1n4004 power ratings, 1n4004 applications Hi Guys! I welcome you on board. Happy to see you around. In this post today, I’ll walk you through the Introduction to 1n4004. The 1n4004 is a diode that allows the current to flow in one direction only. It blocks the flow of current in the opposite direction. It comes with two terminals called a ...