Equivalent Series Resistance

["Eric Davidson" <edavidson-at-icva.gov> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Hi All,
 
ESR (Equivalent Series Resistance) is an important parameter of any capacitor.
It represents the effective resistance resulting from the combination of
wiring, internal connections, plates, and electrolyte (in an electrolytic
capacitor). The ESR affects the performance of tuned circuits (high ESR reduces
the Q factor) and may result in totally incorrect or unstable operation of
devices like switchmode power supplies and deflection circuits in TVs and
monitors. As would be expected, electrolytic capacitors tend to have a high ESR
compared to other types - even when new. However, due to the electrochemical
nature of an electrolytic capacitor, the ESR may indeed change - and not for
the better - with time.  The following website has some valueble information
and some excellent links for those interested in learning more about ESR: 
<http://octopus.freeyellow-dot-com/esr.html>http://octopus.freeyellow-dot-com/esr.html 
Hope this helps.  Coil safely.
 
Eric
<mailto:edavidson-at-icva.gov>edavidson-at-icva.gov