About measure Impedance range of Network Analyzer (AD2)

[Paul Chang]

Dear Sir,

How to know the Impedance range and its ccuracy?

Wavefroms show 1 GΩ~1nΩ. 

 

Best Regards,

Paul

[attila]

Hi @Paul Chang

We don't have such specification but the IA Adapter module has 6 reference resistors ranging from 10R (limited by the AWG output drive 10-50mA) to 1M (500k taking in consideration the scope input impedance). The further away the tested impedance is from the reference the accuracy is reduced. 
https://digilent.com/reference/add-ons/impedance-analyzer/start

Here are some extreme measurements ~1uH (mR with 10R) and 39pF (G with 1M ref)

[Paul Chang]

@attila Thanks for your help.

[EH2]

Hi @attila,

I am wondering if you have general information about the impedance measurement accuracy as well as precision (maybe in %, or a range) with and without the IA adapter module using the AD2?

I know this depends on the given setup as well as excitation and measurement settings, but maybe you have some general information i.e. accuracy of the reference resistors used in the IA adapter, etc. ....
Any help would be appreciated. Thanks 🙂

[attila]

Hi @EH2

Unfortunately I can't give exact number since it depends on many factors.
The reference resistors on the IA Adapter are 0.1%
Use open compensation specially to improve the measurements at high frequencies (higher resistor values) and short compensation for lower frequencies (lower resistor values). You can also use average/averaging.

[EH2]

@attilaThanks for the quick reply as well as the suggestions!

The tolerance of the IA adapter reference resistors is also very helpful to have.