You can simply simulate the on-resistance of the switches as a function of the input voltage. Apply a small fixed Vds (e.g. 100 mV) over the switch and get its ratio to the switch current. You will see then the variation of R which causes non-linearity
I have simulated the on-resistance, but isn`t non-linearity caused by both on-resistance and junction capacitances? The dominating of them is determined by the output impedance of the source. I would like to get a plot of the harmonic distortion (2nd and 3rd harmonic) versus the output impedance of the source.
How can I do this in ELDO?