Advanced Device Modeling Using Automatic Differentiation In A Mixed Domain Circuit Simul

The advent of automatic differentiation, the adoption of object-oriented implementation paradigms, and compiler-support for function overloading enables relatively straightforward implementation of device models with typically 10% of the code required for standard device implementations. In this paper implementation of the EKV model in the fREEDAtrade circuit simulator is reported. fREEDAtrade is capable of transient, wavelet, harmonic balance, large-signal transient noise, DC and AC analyses of circuits using a single device model implementation. Automatic differentiation enables the calculation of device derivatives with analytic accuracy but without errors common in manual development of device derivatives. fREEDAtrade achieves unconditional convergence through the use of parameterized state variables that obviates the end for local convergence control or homotopy techniques. A dynamic range in transient simulation exceeding 160 dB has been achieved