Extending the Open Model Interface API to Update Parameters at Every Timestep of a Transient Simulation

We propose an extension of the Open Model Interface (OMI) API standard that allows to update the model and/or instance parameters of supported compact models at every timestep of a transient simulation. This can be used to make the model behavior dependent on bias conditions and/or device history. One potential application of this method is the modeling of random telegraph noise (RTN). In order to investigate the limitations of the approach in terms of accuracy, stability and simulation runtime, we use it here to add self-heating to a bsim4 model in our in-house simulator. This test case is chosen because an alternative implementation with a thermal subcircuit is available as reference. Our tests show that a mechanism to limit the maximum timestep is required to ensure stability and sufficient accuracy of the simulation results, and this is included in the proposal.