Do we need high frequency inductor for 500kHz DCDC converter

[buenos]

dcdc inductor freq

for a high frequency DCDC converter (500kHz), do we need a high frequency inductor?
or a slower is also good (100kHz)?

The ic manufacturers increase the frequency, to reduce size, but, what I could find, they have quiet bug capacitors at the output. why is tahat? (TPS54356)

 

[zakrotta]

Re: dcdc inductor freq

The higher the frequency the lower the inductance value as the inductor impedance is wL. As for the output capacitance it is used to reduce the ripple of the output voltage and it's value can be reduced by increasing the switching frequency.

 

[dfullmer]

Re: dcdc inductor freq

Hi,

As long as the inductor you are using does not change it inductive value at the higher frequency you should be able to get away with it. The only other consideration is the saturation of the inductor. But if they are both rated for the same DC current then you should be okay. The lower switching frequency inductor would have to deal with higher current spikes then you would be subjecting it to in the higher frequency configuration.


good luck

dfullmer