Dear friends!
I wonder why many circuits use small capacity electrolytic capacitors (less then 100uF) as bypass and decoupling capacitors, rather then ceramic ones? After all, ceramic ones are smaller in size and have a comparable price with better characteristics.
And if ceramics are indeed better, then what type of dielectric is better to use for the stated purposes
I wonder why many circuits use small capacity electrolytic capacitors (less then 100uF) as bypass and decoupling capacitors, rather then ceramic ones? After all, ceramic ones are smaller in size and have a comparable price with better characteristics.
And if ceramics are indeed better, then what type of dielectric is better to use for the stated purposes
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2 cents >
To my knowledge ceramic capacitors are not made in values as high as 100uF > that is why people use electrolytics for such a value.
Ceramics are very good & long stable life for 'very low values'.
'Polly-caps' are generally preferred for low-medium values.
https://www.google.com/search?q=wor...jKgB964ArIHCDAuMS4yOS4yuAfzOg&sclient=gws-wiz
To my knowledge ceramic capacitors are not made in values as high as 100uF > that is why people use electrolytics for such a value.
Ceramics are very good & long stable life for 'very low values'.
'Polly-caps' are generally preferred for low-medium values.
https://www.google.com/search?q=wor...jKgB964ArIHCDAuMS4yOS4yuAfzOg&sclient=gws-wiz
Panasonic polymer hybrid electrolytics (EEH-ZA or EEH-ZC series) have low ESR as in ceramic capacitors but don't have voltage-dependent capacitance as in class II ceramics.
Watch out. Ceramic capacitors can cause some circuits to become unstable, especially some regulators. You need some series resistance in those cases. They can also ring in some switching circuits with other capacitors.
These days I use Poly-Aluminum capacitors for bypass or higher frequency (switcher) filter capacitors. Electrolytic capacitors are sometimes more suitable in line frequency applications.
These days I use Poly-Aluminum capacitors for bypass or higher frequency (switcher) filter capacitors. Electrolytic capacitors are sometimes more suitable in line frequency applications.
Don't know about that. I've mostly used them as LDO output caps where low ESR is required and class II ceramics would need to be paralleled due to derating. E.g. https://www.diyaudio.com/community/posts/7728111/
Hi capslock,
High K ceramics don't make good coupling caps, NP0 / C0G are fine. I am undecided on Poly-Aluminum, I haven't seen any increases in distortion in experiments.
With coupling caps, series impedance usually isn't any concern. The circuit impedance is high enough to swamp any of that out. The voltage co-efficient might be important, I haven't looked at that. Electrolytics for coupling caps are fine.
In applications where the cap is a filter element, everything changes. Leakage current may also be important, and that you have to watch over temperature.
For decoupling (this application for the thread), different story again. Ceramic caps can be fine, as can Poly-Aluminum. I wouldn't waste the money and have a huge package like a Polypropylene foil capacitor. Nothing wrong with it, it's just expensive and huge.
High K ceramics don't make good coupling caps, NP0 / C0G are fine. I am undecided on Poly-Aluminum, I haven't seen any increases in distortion in experiments.
With coupling caps, series impedance usually isn't any concern. The circuit impedance is high enough to swamp any of that out. The voltage co-efficient might be important, I haven't looked at that. Electrolytics for coupling caps are fine.
In applications where the cap is a filter element, everything changes. Leakage current may also be important, and that you have to watch over temperature.
For decoupling (this application for the thread), different story again. Ceramic caps can be fine, as can Poly-Aluminum. I wouldn't waste the money and have a huge package like a Polypropylene foil capacitor. Nothing wrong with it, it's just expensive and huge.