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## What voltage capacitor should I use?

The voltage on a capacitor is not the rating, but rather how much voltage you can expose the capacitor to. For example, if your voltage source is 9 volts, you should choose a capacitor that is **at least double the voltage**, 18 volts or even 27 volts to be safe.

## Are capacitors needed with voltage regulator?

3 Answers. Most voltage regulators (especially LDO types) **require a capacitor on the output for stability**, and it will usually improve transient response even for regulators like the 7800 that may not strictly require it. An input capacitor is usually required to reduce source impedance.

## How do I choose the right capacitor for my power supply?

Do not choose a capacitor based just on the value/voltage combination. **Consider the required dv/dt rating** when selecting snubber capacitors. The dissipation factor determines the power dissipation within the capacitor. Therefore, select an alternative that offers a lower loss factor.

## How do I choose the right size capacitor?

You mainly need to look at 2 values: **the voltage and the capacity** -both are written on most capacitors-. For example, if you are going to charge a capacitor with 24V, you need to make sure your capacitor will support that voltage; so you’ll need a capacitor for at least 25V (plus error margin).

## Can I use a different uF capacitor?

A capacitor is an energy storage device used to regulate voltage output. A capacitor has **two different measures** or “ratings.” The first is the capacitance rating, measured in microfarads and listed on the capacitor as uF. … For example, if your capacitor reads “470uF 25v,” it can hold 470 micro-farads at 25 volts.

## Can I use a 50v capacitor instead of a 25v?

**Yes**. Just don’t go below 25v. The 4.7uF is an “exact” value, whereas the 25v is a maximum rating. Probably yes: Ideally you should replace the capacitor with one of the same nominal capacitance and an equal or greater maximum voltage rating.

## How do you determine the voltage rating of a capacitor?

**Capacitor voltage rating = DC volts + AC component / Kfactor.**

- Capacitor voltage rating = DC volts + AC component / Kfactor.
- Kfactor is dependant on frequency and
- For polypropylene K ~~= 1.16 – 0.16 x log(f) (Numerical values were correct.