Measuring the slew rate in Cadence is similar to measuring it in other simulator. Close the feedback loop of the op-amp and apply a large step voltage to the input of the op amp, and measure the initial slope of the output.
There is not a close relation between slew rate and settling time of an op-amp. Some you can increase the slew rate of an op amp using a nonlinear circuit wile the circuit doesn’t have any effect on the settling time.
Following IEEE papers are helpful to read:
“Relationship between frequency response and settling time of operational amplifiers”
Kamath, BYT; Meyer, RG; Gray, PR.
"Analysis of the settling behavior of an operational amplifier"
Settling time is electrical parameter of opa under small signal, but the slew rate is electrical parameter of opa under large signal. I think they both have no relation.What is the relation of slew rate and settling time.