Polarize and unpolarize capacitor in parallel

A polarized and unpolarize capacitor are conencted in series at the input and output of the voltage regulator. What is the reason for this? To increase ESR?

StupidDum said:

A polarized and unpolarize capacitor are conencted in series at the input and output of the voltage regulator. What is the reason for this? To increase ESR?

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You wouldn't want to INCREASE ESR, if anything you would want to DECREASE it.

The reason for doing it is that electrolytics don't work well at high frequencies, so the non-polarised capacitor gives high frequency decoupling, and the electrolytic gives low frequency decoupling.

BTW, they are in parallel, not in series.

audioguru said:

BTW, they are in parallel, not in series.

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ha! i got no idea why my fingers didnt type according to my brain. parallel became series, decrease ESR became increase ESR.