Under what circumstances can a tantalum capacitor used instead of an aluminum electrolytic capacitor?

Filter with tantalum capacitor is better than with aluminum, if coupling to use filter with aluminum. This theory is not correctly, it depends on the occasion. Tantalum capacitor has great ESR value so that transient overcurrent is poor for using the power of main filter, but the ESL is lower the wind aluminum electrolysis. The high frequency filter is better than aluminum electrolytic that is suitable for the high frequency component of auxiliary filter. "Good filtering with tantalum capacitor" is not serious theory, sometimes is wrong." Coupling with aluminum electrolytic is better" is incorrect; the effect of tantalum electrolytic is stronger than electrolytic aluminum. It's not necessary to use aluminum electrolytic while for amplifier the coupling end in existence of positive and negative potential. The best coupling capacitance is low loss tangent with non-polarized and non-inductive.
The ceramic power filter with 22 uF is equivalent to the effect of aluminum electrolytic with 100 uF. But this theory is not exactly at any time, ceramic capacitors have a variety of materials and technology including some models of low capacitor series resistance or low ESL is better that using in filter."22 uf is equivalent to the effect of aluminum electrolytic with 100 uF" is not exactly. In 50 hz filtering, this theory is correctly. The merits of ceramic capacitors are reflected while using the filter with power switch. Noted that is not all ceramic capacitor has this feature, it need to use X5R or X7R material.

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