Electronic – How much resistance does the capacitor itself contribute to an RC circuit


Are the effects of the internal resistance of a capacitor in a non-repetitive RC circuit with an RC time constant of less than a nanosecond significant? I have only been able to find equivalent series resistance ratings for capacitors, which are usually measured at 100 kHz.

Best Answer

You want a rapidly rising magnetic field at ns timescales, and you worry about cap esR?? ESL is more likely to be the gotcha, but even then....

You may want to start by thinking about the inductance of your magnet, and then how much voltage you will need to make the current change quickly in that inductor (Inductors really do not do step changes in current).

By the time you are playing in ns speeds you really want to be thinking EM not just E or H as often your circuit geometry means you have to think fields and waves, not lumped element.