WEBENCH® Tools/TPS61175: Peak Inductor Start up current vs continuous ratings

Dear Sir,

Do you mean the inrush current is 3 times bigger than the inductor  current rating? This is really too much.

Recommended circuit? I can't understand it. Where did u get it?

Dear Sir,

Thanks for the update.  it depends on the inductor you chosen.

For the powder core inductor, it is of soft-saturation characteristic, even with a 3 times higher current, it still has some inductance, for those kind of inductor, it is OK to withstand a larger current for a short time(like 1-10ms) during startup.

But for the ferrite core inductor, the core will saturate once the biggest current exceeds the Isat or the Imax specified in the datasheet.

So you need to know the normal max current in your application and the inrush current during the startup.  Generally,  if the inrush current is much higher than the biggest normal working current, then you need to select the inductor carefully. It is safe that the Isat is higher than the inrush current. But if Isat< inrush current, then you need to check with inductor supplier.

Could you please show me your inrush current waveform and the inductor datasheet?

Dear Sir,

Yes, turn on the power supply slowly can help to reduce the inrush current. And by the way, use less caps at the output side also helps.  But you need to make sure the output caps are enough for the application.