Well, reading the documentation (cdsdoc) would have allowed you to work this out for yourself.
For those unable to research simple things themselves, here's what you'd do:
Code:// your circuit is here somewhere
// this source may already be in your circuit, but this
// is for illustration
vctr1 (Vctr 0) vsource dc=0
ctrsweep sweep dev=vctr1 param=dc start=0 stop=1 step=100m {
tran1 tran stop=100n
}
Regards,
Andrew.