Connect with us

Q factor

Discussion in 'Electronic Design' started by jason, Mar 21, 2005.

Scroll to continue with content
  1. jason

    jason Guest

    Hello All

    Say Impedance Z i = jwL + Rs
    (Rs is in series and it is actually the internal series resistance,
    this means inductor is an ideal one)

    So if we assume this way, then does it mean jwL comes from the ideal
    inductor? Not from any of the Rs at all?

    If we want to find Q of the inductor
    we will use Q= wL/Rs where SL(or jwL) is not involved totally in the Q

    Am I right ?
    Kindly enlighthen
    Thank you

  2. Tim Wescott

    Tim Wescott Guest

    If your actual inductor acts exactly like a perfect inductor in series
    with a resistor yes. Otherwise no. Many times in RF work your actual
    inductor will either act like it has both series and parallel loss, or
    (probably closer to reality) like it's transformer-coupled to a lossy
    circuit. This is why if you plot the Q of an inductor against frequency
    it'll come to some broad peak then slip down again.
  3. Mark

    Mark Guest

    The RF sereis resistance goes up with frequency due to the skin effect
    so this alone can cause the Q to level off and decline at higher
    frequencies giving the broad peak.

Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day