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Aluminium Electrolytic Capacitors for automotive use?

ku637

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Hello,

I have a buck regulator that needs working from 12V input to provide say 5V/10A max output.

It may see some load steps in the output in the range of 6A , I want the dip/overshoots in the 5V line to be minimum.

So i checked and it seems it can require capacitance in the range of ~200uF to achieve the same.

So looking on to my options i see mostly Aluminium electrolytic type is i find ..

Also I may see a ripple current in range of 0.4 to 0.5A

Is it recommended to use aluminium electrolytic capacitors here . This product is expected for automotive application and do Al-caps have device life time limitation and generally what is the approach in automotive industry for such applications.

Is there much advantage using polymer type electrolytic caps.

Thanks for any help
 

KlausST

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Hi,

What ripple current do you expect?

Klaus
 

    ku637

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schmitt trigger

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For automotive applications, there are four major subcategories: Powertrain, Chassis & Safety, Interior and Exterior.
The margins and requirements are different.

Reputable vendors like Nichicon, have online selector tools depending to select the most appropriate device.
For instance:

 

    ku637

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ku637

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Hi,

What ripple current do you expect?

Klaus
Ripple current is 0.5A.

For automotive applications, there are four major subcategories: Powertrain, Chassis & Safety, Interior and Exterior.
The margins and requirements are different.

Reputable vendors like Nichicon, have online selector tools depending to select the most appropriate device.
For instance:

Thank you for pointing out. My application falls under "Interiror"

So i understand that Al-electrolytic capacitor is commonly used in automotive. Now coming to the life time i hope typically automotive products may require to be working close to 10- 15 years.

So in such a condition, the capacitor life time can be a major factor right?

So i have seen certain life time calculators with certain suppliers which calculate the total device life time.

And i feel keeping the temperatue , ripple current down is key to achieve long life and 15years is achievable as per caluclation there. But not sure about practical things

 

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