SMD multiple pad decoupling cap

Discussion in 'General Electronics Chat' started by jamus, May 23, 2014.

  1. jamus

    Thread Starter Member

    Feb 11, 2013
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  2. alfacliff

    Well-Known Member

    Dec 13, 2013
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    lower ESR and inductance
     
  3. enggricha

    Member

    May 17, 2014
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    I am curious about this too... how do the multiple pads contribute to low ESR and Inductance.
     
  4. THE_RB

    AAC Fanatic!

    Feb 11, 2008
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    Because the silicon chip is large, and a cap on one side could only be connected to the other side of the chip by thin traces within the silicon. So the little doodads on the other side of the silicon get poor capacitizing.

    If you put caps on both sides (or all 4 sides) of the silicon chip the caps are closer to all the little doodads on the chip. :D
     
  5. enggricha

    Member

    May 17, 2014
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    not sure i got it, but will study this in details when i find time. Thanks for explaining.
     
  6. #12

    Expert

    Nov 30, 2010
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    I think I'm in love. A capacitor with 4 pairs of connections!
    4 inductors in parallel have less impedance, like 4 resistors in parallel. Great way to get lots of conduction in a small space:p
     
  7. Markd77

    Senior Member

    Sep 7, 2009
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    Then you will like the one with 10 pads (2 are on the ends).
    Their explanations are on pages 148 and 152 of the datasheet. Odd numbered pads are one terminal of the capacitor, even pads the other.
     
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  8. THE_RB

    AAC Fanatic!

    Feb 11, 2008
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    Hahaha! I just realised that I was the only person in this thread talking about why an IC (silicon chip) has multiple pads to connect to multiple capacitors!

    Face palm moment. :D
     
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