[ADS] designing series coils (spiral inductors)

the value of my coil (spiral inductor) is very high. due to this, I would like to reduce the size of the coil by replacing it with multiple coils connected in series. my PCB board has 6 layers. each layer from layer 2 onwards will have a coil and all of them will be connected together with a via (series connection). i dont have any coil on the Top layer.

the problem with ADS is, coil need MSUB definition which needs a ground plane underneath. how do I define my series coil connection in 5 layers as above? does each coil treat the coil below it as a ground plane ? or shall I state H (substrate thickness) as a infinite number since there is actually no ground plane underneath these coils, its just the next coil.

You are designing a multilayer inductor, it can be modelled by the MSIND (micro strip inductor) model. Using it gives completely wrong results because it doesn't consider the coupling. I don't think that ADS has a ready-to-use model for multilayer inductor. Momentum or any other 3D solver should be able to derive a S-parameter model.

Hi FvM,
Yes, I'm using MIND. i understand ADS will only give the calculated pure inductance for the MIND. it doesn't take into account the coupling between windings and coupling between the coil on one layer to another.

but those coupling will generate capacitance which will cancel out the inductance i pressume. what do you think?

That's correct. Forget the schematic models for this task! You need to build a scalable artwork cell (I recommend AEL coding for that) and simulate with Momentum.
http://muehlhaus.com/support/ads-app...es/ael-artwork

thank you so much Dr Volker. i will look at scalable arwork cell for my design.