3DB bandwidth expression

Hi All,

I am trying to evaluate a function using the expression editor but am getting an error. This is for bandwidth of differential output divided by the differential input as shown below.

 bandwidth(((VF("/vop") - VF("/von")) / (VF("/vip") - VF("/vin"))) 3 "low")

Will be helpful if someone can point the issue with using this expression to compute the 3db bandwidth. I have tried this expression both using AC & Tran analysis but nothing evaluates.

I am also need to use this expression in the MC analysis.

I am using IC618

Regards