Reproducing a circuit with non linear components from netlist

[sriram1828]

I would like to see how all the parameters of a transistor model are connected as a circuit. when we are trying to use a transistor in a circuit spice converts it into its linear form by replacing it with its linear representation. I would like to know what transistors linear representation looks like.

1. For this I've chosen BSIM 4v4.5 transistor model (because i know how a level 3 linear representation look like).
2. I'm trying to import this model into either hpsice or ng spice, create a netlist by implementing it in a test circuit(say inverter).
3. Take the netlist file and try to reproduce the transistor linear form.

It'd be really great if anyone helps me through this, like what kind of software makes it easy to be done.
I'm not sure which tool helps to reproduce a circuit from its netlist.

PS: i would like to include every important model parameter of the model BSIM4 v4.5 (around 30)

I'm a naive person in this area of expertise, so correct me if i'm wrong.


Thanks in Advance.

 

[erikl]

You would need a transistor model which is supported by BSIM 4, i.e. a level 49 or 54 model, which contains all the necessary parameters (usually a lot more than 30).

 

[sriram1828]

Thank Erikl,

As is said i'm trying to use either bsim 4.6.0 or bsim 4.5.0

**broken link removed**

Can you tell me how to implement these models and create a netlist.

Can you suggest me any software that i can use to reproduce the circuit from the netlist. ?

Is there any way we can get the linear representation of a transistor other than reproducing it from the netlist ?

 

[erikl]

Can you tell me how to implement these models and create a netlist.

If you know the parameters, you can create your own model. Or get one from PTM latest models, e.g. a BSIM4 level=54 90nm model.

Can you suggest me any software that i can use to reproduce the circuit from the netlist. ?

EDA Analog IC Design tools can do this, e.g. Cādence Virtuoso, Mentor, ...

Is there any way we can get the linear representation of a transistor other than reproducing it from the netlist ?

In principle by creating an appropriate behavioral model. But it would be rather complicated to include all that behavior which is included in the BSIM4 mathematical model description.
That's why such models are developped, isn't it?

 

[sriram1828]

Thanks Erikl,

Obviously, but for the research i'm a part of require how spice replaces the transistor with its equivalent model in the sparse matrix while performing MNA. So i thought i could give a try this way.

It'd be really great if you suggest me a better idea.

 

[FvM]

how spice replaces the transistor with its equivalent model in the sparse matrix while performing MNA

It should be quite obvious from descriptions of circuit simulator operation what SPICE or any SPICE based simulator does.

It performs an initial transient solution to determine the operation point, then calculate the node impedances/admittances for each AC analysis frequency point. The set of transistor model parameters is effectively reduced to a low order model in the first step.