LM5010: Output capacitor is mix of electrical capacitor and ceramic capacitor

Hello Kohei san,

(EDITED) sorry just saw you are using it on the output of the LM5010.  Ripple injection should be considered at switching frequency.  The Ceramics has an ESR much less than that of the Electrolytics you are using. See below. Elec ESR calculated from the tan delta.

220uF Elec  Est ESR ~1.5ohm

22uF Elec  Est ESR ~18ohm

22uF Cermaic ~3mR

the Output capacitance can be considered as the Ceramic and the equivalent ESR is also as the ceramic.  Cout ~22uF and Cout ESR ~3mR for Fsw>100kHz 

You will need to use Type III ripple injection detailed in the datasheet.

There is a paper written on parallel capacitors below.

http://www.how2power.com/pdf_view.php?url=/newsletters/1103/articles/H2PToday1103_design_National.pdf

Hope this helps?

David.