I am new to electronic design (textbook taught hence practical experience limited), and upon reading the BOM of an EMI filter I noticed an asterisk *. Is this indicating that for CX1 there are eight capacitors in parallel, or does the asterisk indicate something else I am missing? I have not found a parallel of this on other EMI filter designs (design + BOM) with other DC DC Converters.

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The DC DC converter is Delta Electronics'E48SC32009NRDH - https://www.mouser.ca/datasheet/2/632/DS_E48SC32009-1385692.pdf

I apologize in advance for the rudimentary question, and thanks for taking the time to read through.

  • 2
    \$\begingroup\$ I would assume so. \$\endgroup\$
    – crasic
    Nov 27, 2019 at 16:17
  • \$\begingroup\$ Could they possibly mean that the value of CX1 can be 2.2uF - 17.6uF? I have never seen eight capacitors in parallel on any input filter, but I am a novice. \$\endgroup\$
    – t3ddftw
    Nov 27, 2019 at 16:18
  • 2
    \$\begingroup\$ @t3ddftw unlikely, likely it is draw this way because the datasheet hints that it assumes electrolytic (in the text) , and parallel caps are how one reduces ESR , which does matter for filters , but perhaps 8is overkill. \$\endgroup\$
    – crasic
    Nov 27, 2019 at 16:24
  • \$\begingroup\$ I thought it was recommending the low ESR electrolytic for the input bulk capacitor (CX3), Im trying to contact the manufacturer however I havent recieved a reply in four days now. Thanks guys! \$\endgroup\$
    – FuzMunkey
    Nov 27, 2019 at 17:42


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