Hello rbacchi,
You were on the right track. I’ve applied the .MEAS directive to this simple second order RLC circuit:
I’ve chosen the components values ​​to make it quite underdamped:
go to “View” menu, and click SPICE Error Log file (or CTRL+L).
the higher value is the settling time. If you want a 2% settling time, simply set settling_percent=2.