cadence transformer
I want to simulate a transformer in Cadence Virtuso.
The transformer should include the models of practical inductors.
What should I do?
Put 2 inductors with serial resistances and assign a mutual coupling coefficient between them..
And also, you can connect parallel capacitors and other stray components as you wish..
So, transformers can be modelized with equivalent passive components
How to assign a mutual coupling coefficient between them?
In analogLib, there is a "mind" component, you can use it to couple for two inductors
you can use simple unductors and the coupling element from the analog library or you can use the T-equivalent of the transofrmer and simply use inductors (if it is not accurate enough you can use other equivalents also). You can define Verilog-A model also and I have some kind of "nightmare" that there is a transformer component in the passiveLib ( I have to double check that).
SO, there are many possibilities ... and you can find cadence application notes how to model ferrite core (if you need that)
Many thanks at first.
The thing is I have a inductor symbol of the technology that I use
I tried to use it in my circuit
Bu the "mind" only works with ideal inductor"ind"
I can not use it to define the mutual inductance between other kind of inductor
It seems that another tool is necessary in order to perform this kind of simulation. You may either use an EM solver (importing the layouts of both the inductors and defining their relative placement) but this is going to take several hours. Another solution you could try that will give you EM-accurate results is VeloceRF.
http://www.helic.com/VeloceRF
Let me know if you need anything further.
--padpan
the solution is to add parasitic resistors and capacitors to the transformer to make it the actual transformer model
Yes, if you did so you would get a more realistic model, however parasitic resistor should vary over frequency otherwise skin effect losses will not be accurately modeled.
--padpan