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Capacitors and Inductors values

  1. Oct 14, 2007 #1
    So being fresh from school, a lot of times as students we dealt with unrealistic values for caps and inductors. I remember doing a textbook problem where a cap's value was 1 F. Now that I'm in the real world. What is considered to be a realistic value? To push the question further, I see a lot of schematics with caps used as coupling caps, how do they go about picking such value? What is considered to be a small cap? 1 pF? Whats a big cap? 1 uF?
  2. jcsd
  3. Oct 14, 2007 #2


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    Science Advisor
    Gold Member

    What is big and what is small is relative to the application. In audio work, the typical capacitor used for a coupling cap would have a large value compared to a coupling cap used in VHF. A power supply filter cap filtering out 120 hertz would have a large value compared to one filtering out 30 KHz from a switch-mode supply.
  4. Oct 15, 2007 #3
    I had a feeling that the answer to my question related to the application.
  5. Oct 15, 2007 #4


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    Staff: Mentor

    It's true that it will vary by application, and by circuit functionality. But in general, caps will be in the pF to uF range, inductors will be in the uH to mH range, and resistors will vary a lot, but mostly will be in the Ohms to 100kOhm range. Yes, 1F caps are very rare, except in very specialized applications.
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