Can Replacing Chip EMI Filter Capacitors Improve Attenuation Characteristics?

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Replacing chip EMI filter capacitors can potentially improve attenuation characteristics, especially when considering a replacement with a tolerance of -20/+50%, which may yield higher capacitance values and insertion loss. The effectiveness of the replacement also depends on the filter topology, such as whether it is a "T" or "Pi" configuration. The original and replacement capacitors are both 3-terminal feed-through types, which have low series inductance. The overall filter performance will be influenced by additional components used in conjunction with the feed-through capacitor. Proper selection and configuration are crucial for achieving optimal results.
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I have some chip emi filter capacitor type. Its parameters are size 0603 , 1000pF , tollerance +/-20%. I would like to replace it by filter of another vendor, with the difference of tollerance -20/+50%.
As I'm understanding from attenuation characteristics chart, the replacement maybe even better, cause for +50% tollerance I will have a chance to get higher capacitance value and higher insertion loss.

Is it correct?

Thanks
 

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Can you post a link to the datasheets? It takes more than a capacitor to make a filter -- what is the topology of the filter? A "T" or a "Pi" maybe? What is this tolerance on? Just the capacitor, or something else about the filter?
 
One of them is Murata, NFM18 series: http://search.murata.co.jp/Ceramy/CatalogAction.do?sHinnm=?&nbsp&sNHinnm=NFM18CC102R1C3&sNhin_key=NFM18CC102R1C3B&sLang=en&sParam=nfm18
And the 2nd is SMI, SGM16-2A series:
http://www.smied.co.jp/smi_english/product/noise2006.pdf
 
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Hmmm. So these are 3-terminal feed-through capacitors, with low/negligible series inductance. So to answer your original question, yes, the 2nd part should do as well or better than the muRata Erie part.

The filter characteristic will depend on what other components you place in series with the feed-through capacitor.
 
Thanks a lot.
 
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