• TI Thinks Resolved

TS5MP645: S-param model (without parasitic)?

Prodigy 20 points

Replies: 3

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Part Number: TS5MP645


I found this thread 


which has an S-param model, Adam Torma mentions it includes extra trace length and board parasitic. 

Does an updated S-param model exist, and if not can you share the stackup / extra trace length included in this model so that we can potentially remove similar amount of trace length from our own signal path? 



  • Hi, Kevin,

    I would recommended to use the S-parameter model on the product folder page

    Measurement of this model was done using a calibrated VNN. De-embedding method was applied to ensure we are only characterizing the response of the IC itself excluding parasitics such as board trace, sockets, cables and connectors. 



  • In reply to David_Wang:

    Hi David,

    According to my SI team, the second model you gave is in 'snp', XPEEDIC SnpExpert format, not a regular S-parameter format. This is a toolchain we're unfamiliar with. Can you provide a more generic S-parameter format for other tools like Sigrity / Ansys / HSpice / ADS? 

    I believe the first model I mentioned is in the correct format but has undesirable parasitics, which we'd like to either understand more about so that we can remove that section of rigid PCB parasitics, or have a model in that file format without parasitics. 



  • In reply to Kevin Pham1:

    Hi Kevin,

    Sorry for the late response.

    The TI web site does have the s-parameter model files in “generic” format…  Looking at what is available on ti.com, I downloaded the S-Parameter Model zip file and extracted everything. Inside are 4 files - a “Port_Order” ppt and 4 .snp files.  The .snp files would be the data in generic S-parameter format.  The ppt tells you which ports to extract from the corresponding .snp files to get the desired curve,  and how to do it… 

     So for ADS or whichever simulation tool you are r is using, you would need to import the file and then connect (or plot, etc.) the proper Sxy parameter.  For example, if  you wanted to look at the D2_A_P (A side, Positive) curve then you would plot/connect S1513 (port 15 for D2_A_P, port 13 for D2_COM_P).