Zener Diode
A heavily doped silicon p-n junction diode designed to operate safely in reverse breakdown mode to maintain a precise reference voltage.
Governing formula
V_out = V_Z (constant in reverse breakdown)
SI unit
V (Volts)
In depth
Under reverse bias exceeding breakdown voltage V_Z, controlled quantum tunneling or avalanche breakdown allows significant current flow while maintaining constant terminal voltage.
Examples in the real world
Zener diode voltage regulator circuits supplying stable 5.1 V reference power to delicate electronic microcontrollers.