ESr for inductor/capacitor theory

[vaibhavpawar]

I am trying to understand inductors and capacitor's basics. ESR is the factor which we consider while using inductor/capacitor.

My question is low ESR inductor is good or bad for design? For power inductor and filtering inductor, what is ideal ESR?

Same with capacitors, if ESR is low is it good for application? High ESR in tantalum is good for loop stability and compensation.

All this sounds contradictory to me. Please someone elaborate above points for understanding concept.

 

[malli_1729]

Power inductors will have DCR ( DC resistance) which decides copper losses inturn temperature rise.
Capacitors have different applications. Low ESR --> More ripple current capability with less temp rise. It will be good or bad based on scenario. Let us know what exactly you want to know.

 

[vaibhavpawar]

For power inductor used in DC-DC converter and for application of filtering ripples across o/p, what will be ideal value for ESR in both cases? Thank you.