Transistorgrab

Z-Diodes are often used for simple voltage stabilized circuits. It is very important to use the Z-diode with the correct parameters.
This article shows an example for the voltage characteristics of two Z-diodes.

The reverse voltage of a Z-diode depends extremly on its reverse current. In data sheets the Z-voltage is given for a given reverse current.
If the reverse current is much more different than that value the Z-voltage is very different.

The following figures shows the Z-voltage over the reverse current from 0.5..30 mA of two Z-diodes with a nominal Z-Voltage of 2.7 V

Figure 1: comparison of two 2.7 V Z-diodes at 5 mA reverse Current

Figure 1 shows that both Z-diodes have their nominal Z-voltage at a reverse current of about 5 mA.

Figure 2: Comparison of two 2.7 V Z-diodes

Figure 2 shows the whole voltage characteristics. It shows that at 2.5 mA the Z-voltage is only at 2.5 V. At 10 mA the voltage is at 2.9..3 V.