core air gap maked own way question

[analogowyziou]

Hi I have a problem im designing a step up smps and i calculated that i need an etd39 based inductor witm 1mm air gap. But unfortunately the cores with air gap are much more expensive than the same without that gap. So my question is : Can i make a gap by putting a dielectric material between the two parts of a core?
please help me.
sorry for my english, im from Poland.

 

[29285]

Hi I have a problem im designing a step up smps and i calculated that i need an etd39 based inductor witm 1mm air gap. But unfortunately the cores with air gap are much more expensive than the same without that gap. So my question is : Can i make a gap by putting a dielectric material between the two parts of a core?
please help me.
sorry for my english, im from Poland.

Certainly you can do that!
For a gap of 1mm total insert 0.5mm isolating sheet (plastic, paper, rubber, whatever is non-conductive) between outer legs. This is the standard method doing prototypes!

 

[analogowyziou]

Thank you. And by the way will 3c90 material be suitable for this topology ?because I'm not 100% sure about that.

 

[AndrewT]

For audio frequency transformers one can do the same tweak in C core and EI style steel transformers/inductors

 

[Pafi]

will 3c90 material be suitable for this topology ?

It doesn't depend on topology, but operating parameters. (Maximal flux density, rate of change.) But the answer is very likely yes.