Best capacitors for sallen-key low pass filter

Discussion in 'The Projects Forum' started by przemmo, Jan 6, 2009.

  1. przemmo

    Thread Starter New Member

    Jan 6, 2009
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    Hello,
    I'm going to design such a filter and want to ask You which capacitors are best for that. The Fc is about 2kHz. Polistyrene? Ceramic?


    thx
     
  2. beenthere

    Retired Moderator

    Apr 20, 2004
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    If you need to have a close fit to the calculations, choose a film type capacitor with at least 5% tolerance - 2% is better. The greater the tolerance, the more uncertain the actual onset of the filter.
     
  3. SgtWookie

    Expert

    Jul 17, 2007
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  4. KL7AJ

    AAC Fanatic!

    Nov 4, 2008
    2,039
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    It's important that the capacitors have low residual inductance. Ceramics are very good in this regard, film capacitors run a close second. Avoid electrolytics at all cost.

    eric
     
  5. przemmo

    Thread Starter New Member

    Jan 6, 2009
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