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Question regarding capacitor type in reference filter described in Analog Dialogue article.

I recently came across an Analog Dialogue article "Why Does Voltage Reference Noise Matter?".

It perfectly described one of the problems I encountered while trying to get the best performance out of the 24b ADC I am using.

The following question refers to the online version of this article:

Sadly, contacting the author Mr Shah directly is not possible, because he recently left ADI and is now working fo another company.
This is the reason I am asking in the forum.

In the test circuit description, it says there is one 10uF Wima capacitor.

I assume the capacitor Mr Shah is referring to here is C7? (Please correct me if I am wrong)

According to the test circuit description, all other capacitors are MLCCs.

My question is:

What kind of capacitors are used in the reference filter?

They seem to be too large in value to have a type 1 ceramic as the dielectric. 

While using type 2 ceramics in my capacitors, I had severe problems with vibrations being picked up by my filter due to the microphonic behaviour of type 2 ceramics.

I tried using aluminium electrolytics and tantalum capacitors, but their (temperature-dependent) leakage and dielectric absorption messed up the DC-accuracy of the reference. 

Furthermore, dampening or getting rid of slight vibrations is not possible in this use case.

I have not yet tried MLCCs with flexible terminations, but before continuing to search for a solution to my problem, I wanted to ask you about some further information about the type of capacitors used in the article.

It would be a great help, if you could give me some further information on the topic.

Thank you very much in advance.

Kind regards,

Moritz Ehrensberger