22 July 2021

Zener diode - today we will work in the reverse bias

The Zener diode is another semiconductor element that is widely used in electronics, mainly for voltage stabilization or device protection. It is used in a reverse circuit compared to a conventional rectifier diode. That is, it has a positive voltage at the cathode and a negative voltage at the anode. It thus works in the inverse direction. When the so-called shut-off voltage is reached, a non-destructive breakdown occurs and the diode experiences a loss as specified by the manufacturer. This drop is usually very precise. When two zener diodes are connected in reverse polarisation with an AC supply, the peak voltage is limited because in the pass direction the diode behaves the same as the rectifier diode and a 0.6 V dropout occurs. This is the so-called Zener voltage.

The main difference between a Zener diode and a rectifier diode is that, when the rectifier diode is connected, it does not pass current in the closing direction and the diode is destroyed when the closing voltage is reached.

MDD manufactures zener diodes in the following housings:

SMD design:

  • DO-214AC (SMA)
  • SOD-123FL
  • SOD-123
  • SOD-323
  • SMAF
  • SMB

Classic design:

  • DO-15


Zener diode - today we will work in the reverse bias