TPS2120: Minimum value of Soft Start Capacitor(CSS)

Hi team

My customer asked minimum capacitor value of soft start.

Customer have removed Css for reduce switchover time(ton) to a minimum.

But they have confirmed that switchover time increases(ton) when there is no CSS.

We didn't find information about minimum Css value at the Datasheet.

- I checked Table 1, Figure 6 and Equation 10, but I don'n find minimum Css value.

Please shared information of about minimum Css value.

Thank you