How to measurement of Zener diode?

Last Update Time: 2019-10-28 10:30:51

Digital multimeter is not suitable for measuring Zener diode for its own design reasons. This is because if we use a digital multimeter to measure the Zener diode, we can only use its diode block, and the open circuit voltage of the digital multimeter's diode block is fixed (we take UT61E as an example, the diode block open circuit voltage is 2.8 V).


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When the Zener diode is measured using UT61E. If when the voltage value of the diode is less than 2.8 V, whether it is red positive and black negative (this is the normal pen order to measure the PN junction) or red negative black positive (this is the reverse breakdown pen order), the multimeter will show the number.

 

Readers can take a Zener diode with a steady voltage of 2.2V. The measured results are as follows: red positive and black negative, voltage drop 0.7V (positive voltage drop of normal silicon diode) and red negative black positive voltage drop 1.6V (voltage drop of Zener diode after reverse breakdown).

 

However, if the voltage stable value of Zener diode is larger than the open circuit voltage of digital multimeter diode blocking red pen, the forward voltage drop of Zener diode can only be measured, and the inverse voltage drop of Zener diode can not be measured because the voltage of red pen is lower than the steady voltage value (infinity). At this point, the digital multimeter will not have the ability to break through its PN junction to obtain a measured pressure drop.

 

In contrast, the pointer multimeter is more suitable for the measurement of Zener diode (its electrical barrier should be used).

 

This is because the resistance of the pointer multimeter is different in different multiples (Rx1k block, Rx10k block, etc.), and the open circuit voltage of the red pen is different. When it is a Rx1k block, the voltage is about 1.5 V: when it is a RxI0k block, the voltage is about the battery voltage of the multimeter built-in battery (such as 9V). Therefore, such a pointer multimeter can measure Zener diode with a voltage stabilization value less than 9V.

 

However, if the voltage stability of a Zener-tube exceeds the maximum voltage of the pointer universal meter, the pointer multimeter will not have the ability to break through its PN junction to obtain the real resistance that can be measured.

 

larger than the "low potential" and less than the "high potential".

 

If you want to know more, our website has product specifications for Zener diode, you can go to ALLICDATA ELECTRONICS LIMITED to get more information