Decoupling capacitors models

[joniengr081]

I am looking for models of SMD ceramic de-coupling capacitors that defines ESL and ESR in different packages like 0603, 0805, 1206 for different capacitance. Do we have a database or online calculator to find these models ?

[Kean]

Several of the large manufacturers have websites to view typical MLCC parameters.  Very useful when you are interested in details of higher value MLCC which often do not meet labelled values in common usage.

e.g. Murata SimSurfing https://ds.murata.co.jp/simsurfing/index.html?lcid=en-us
Enter part number like GRM155R71E104KE14 (or use the dropdowns to narrow search) and you can then enable various graphs like DC bias, Temp, S-params, & |Z|, R, L, etc

I can dig out links for Samsung, TDK, etc if needed but I think they aren't as comprehensive.  SimSurfing does have a very busy screen though.

[joniengr081]

Hi, I have look at the website you have mentioned and search for the part number as your provided as an example. It actually provide all the details including impedance but I am looking for one value for ESL and one for ESR that can be used as a model of decoupling capacitor in HyperLynx PI tool.

[lutkeveld]

Hyperlynx supports s-parameter models (touchstone), so it's better to directly use those.
You can download them from the Murata Simsurfer catalog

[joniengr081]

Yes, it support s-parameters but I am not very familiar with these parameters. I am trying to add a custom model using ESR and ESL. I have attached a datasheet of a capacitor in which impedance and inductance as a function of frequency are plotted. How we can get one value ESR and ESL ?

[Kean]

OK, for a Kemet part you can use K-SIM.
I can't find that exact part, but a similar one would be https://ksim3.kemet.com/capacitor-simulation?pn=C0603C102J5GACAUTO
Again you can download data in S2P file, but also a Spice model, and Kemet also have CSV downloads for each graph which may be easier for you?
Alternatively, you could always use an LCR meter or VNA to measure sample(s) of the part yourself at the frequencies of interest.

[joniengr081]

Thanks for sharing the link. I have opened the link and found the graphs for different parts. I saw impedance and ESR graph. ESR seems to be lower then impedance, probably because of loss consideration in ESR.

Regarding impedance and capacitance I am not able to find a single value ESL. The whole graph is shown in which there is no ESL. How about calculating by formula:

f_res = 1/ ( 2 x Pi x Sqrt(L x C)).

f_res can be found from the impedance graph, the frequency where the impedance is low.
C is known
L can be calculated from the equation above. Would the calculated L be ESL ?

[Kean]

I've never had to calculate it before, but yes the ESL can be found that way using the knee frequency from the impedance graph.

https://circuitdigest.com/tutorial/understanding-esr-and-esl-in-capacitors