Voltage controlled SPST

This component models a single-pole, single-throw switch. When the control voltage is greater than Von, the switch has a resistance of Ron. When the control voltage is less than Voff, the switch has a resistance of Roff. When the control voltage is in between Von and Voff, the resistance is between Ron and Roff and is a based on a smooth logarithmic function which is designed to assist convergence when the switch changes states.