Bulk and Decoupling Capacitors

Hi all,

May I know why Bulk capacitors and Decoupling capacitors are used ?
And how to select those capacitors according to operating frequency (formulas or concepts if any) ?
Please do add more information.

You can find a lot of information here: https://www.physicsforums.com/showpost.php?p=3861831&postcount=2

If you have any queries after that, feel free to ask here or you can search on Google as well:
Bulk Capacitor and Bypass Capacitor

Hope this helps.
Tahmid.

This is one of the best articles I have read on decoupling techniques. It is worth a read:

http://www.piclist.com/techref/power/decouple.htm

AVX and other cap companies have lots of data sheets..
www.avx.com/docs/techinfo/dcplbsc.pdf
Even with small SMD (0402 and smaller) caps next to power pins todays high speed digital intefaces decoupling is becoming more critical. The use of caps is only good up to a surprisingly low speed, then planar capacitance and on die capacitance becomes critical. Inductance and capacitor size are the limiting factors, so you cannot say one value will work for a certain frequency, it depends on the case size and parasitic inductances. Power delivery system verification and simulation software is becoming more prevelant these days allowing complex designs power supplies to be checked for both dc and ac functionality, the ac simulations allowing you to tailor your decoupling and supply lay out to achieve the lowest possible impedance for the desired operating frequency of the design.

Thank u all for your kind help
It was totally worth