Electrolytic capacitor over ceramic or tantalum - where, when?

I have some old electrolytic capacitors of small values like 0.22 µF, 1 µF etc lying around. Knowing that ceramic capacitors are generally better in high-frequency applications like power supply decoupling in digital circuits etc, that ceramic capacitors are available in capacities up to a number of µF's these days (cheap too), and that they don't suffer from some aging problems typically associated with electrolytic capacitors, I wonder:

In what scenario (if any!) would you prefer a small-value electrolytic capacitor over say, a ceramic or tantalum capacitor of similar value / voltage rating. :?:

For the purpose of this discussion, I'd prefer to ignore pricing aspects or the conflict-mineral issues associated with tantalum, and focus on the technical aspects. Also not why other capacitor types would be better, but the other way around: where/when the common electrolytic type rather than other types, and why?

Your ideas?

Dear RetroTechie
Hi
As you probably know , we have an equivalent circuit for each capacitor . it will has a leakage resistance and an ESR and an ESL , for electrolytic capacitors the ESL and ESR , are a bit higher . hence at SMPS design and transmitter design , we have to use an electrolytic capacitor in parallel with a ceramic capacitor , or some electrolytic in parallel together , and then in parallel with a ceramic capacitor .
Best Wishes
Goldsmith

You might use an electrolytic over a ceramic in a high vibration environment.

Tantalums sometimes have issues with large inrush currents.

goldsmith said:

hence at SMPS design and transmitter design , we have to use an electrolytic capacitor in parallel with a ceramic capacitor , or some electrolytic in parallel together , and then in parallel with a ceramic capacitor

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The "have to" is key here - in applications like a SMPS, you'd typically use an electrolytic capacitor because high voltage / large-capacity ceramic or tantalum capacitors aren't practical, available or too expensive. So you'd use a relatively cheap electrolytic to provide the bulk of the capacity, and put other type(s) with smaller capacity in parallel to improve overall behavior.

That isn't what I asked about - I was referring to smaller value capacitors in situations where pricing isn't important and -in principle- a ceramic or tantalum (or other type) could easily take the place of an electrolytic. In such a situation, what technical reason(s) can you guys think of, to prefer an electrolytic instead?

Did you correctly read that what i wrote ? i wrote in parallel with electrolytic capacitors . it is clear that they are not useful lonely .

Hello RetroTechie,

In what scenario (if any!) would you prefer a small-value electrolytic capacitor over say, a ceramic or tantalum capacitor of similar value / voltage rating.

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Such a scenario might be like,
For example, a low ESR capasitor of 0.01uF(ceremic) is connected to a microcontroller's power supply pin and working as power supply decoupling capasitor of that microcontroller. Now to improve circuit board's overall power supply decoupling, we should not put any 1uF ceremic close to the microcontroller. But we can put 1uF electrolytic there.

From intel's application note AP-125("Designing Microcontroller System for Electrically Noisy Environments"), If we look at the paragraph named "Selecting The value of The Decoupling CAP" (page 14) we will see that 1uF(certainly low ESR) will do more harm(transient over/under shoot) than 0.01uF capasitor(certainly low ESR).

Now if we put extra 1uF ceremic, it will get paralleled to 0.01uF ceremic and will do more harm. But if we put 1uF electrolytic it can not be get direct paralleled to 0.01uF ceremic due to electrolytic's higher ESR, and will not form an equivalent 1uF ceremic.

In AP-125's paragraph "Power Supply Distribution and Decoupling" (page 13) it is also said that board decoupler electrolyte capasitors placement in a board is non critical.

AP-125 http://wiki.stei.itb.ac.id/download/attachments/589846/iap125.pdf

Also not why other capacitor types would be better, but the other way around: where/when the common electrolytic type rather than other types, and why?

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I saw in national semiconductor's LM2940 (low dropout regulator) datasheet that the output capasitor must have a critical ESR, otherwise the regulator will start to oscillate.
For wide range of temperature, only solid Tantalum capasitor can maintain such ESR. So solid Tantalum capasitors are very important for LDO regulators.

Sorry for editing.