Multiple dc solution determination using VHDL-AMS

Many circuits such as flip-flops, Schmitt triggers, and negative resistance circuits have multiple dc solutions. The same problem can occur in electrical nonelectrical devices. For many years homotopy techniques have been investigated to obtain the multiple solutions. We present a method that establishes the resulting curve-tracing problem as a network analysis problem using the hardware description language VHDL-AMS. Thus, the curve-tracing problem can be solved with an available VHDL-AMS simulation engine. A special customized simulator is not necessary. The methodology can also be applied to the calculation of transfer characteristics and turning points. This allows e. g. the determination of pull-in voltages in MEMS.