Why is my simulation slow to run a model imported with NETLIST2SL in SimElectronics 1.3 (R2009b)?

I have created a SimElectronics design using that library's N-Channel and P-Channel MOSFET blocks, and everything works fine.

I now want to replace these blocks using a SPICE model imported with NETLIST2SL.

Depending the solver that I choose, my simulation either errors out or runs very slowly (to the point where I need to stop it). Here is the error message that I receive:

 Nonlinear solver: failed to converge, residual norm too large.

 Transient initialization, solving for consistent states and modes, failed to converge.

Answer 1

[MathWorks Support Team]

Because our tools are aimed at multi-domain physical modelling, the solvers work slightly differently compared to dedicated circuit simulators. One result of this fact is that devices should be modelled from a physical perspective. Transistors and diodes will always have ohmic junction resistances, but in SPICE netlists these effects are often ignored. However, adding them to your SimElectronics design helps our solvers, and will either allow the simulation to run or speed up the simulation.

In the R2010a realease of SimElectronics, we ensure that parasitic resistances are not zero.

For releases prior to R2010a, to work around this problem, you can either :

- manually edit the SPICE netlist file and add small values to RS and RD. This will help the solver and should improve simulation performances.

- select a fixed-step solver.