DCDC output capacitor layout

K. Sasaki14

When we put large capacitor and small capacitor parallel as DCDC output capacitor for reducing high frequency noise, where should we put small capacitor.
Is it device side or after large capacitor?
And please let me know that reason.

Best Regards,
Kohei Sasaki

over 9 years ago

0 JohnTucker over 9 years ago

TI__Guru**** 191445 points

as you are trying to reduce the high frequency content towards the load, I put high frequency bypass capacitors after the bulk capacitor. I'm sure there may be other opinions.

0 Helen chen over 9 years ago

TI__Mastermind 40080 points

I usually put it as near the IC as possible, because small cap has lower ESL and is good for absorb the high frequency noise generated from the converter. Which is good for EMI. Especially for the boost converter , whose output cap is in the power switching loop.

Power management

Power management forum

DCDC output capacitor layout