LTspice : An NMOS Current-Sense Model for a Boost

Comes in handy when you're designing a peak-current-mode boost :

Basically use the bi component which lets you do some useful stuff (i.e., write code to do fancy models). In this case, it's a simple model. You only want to pass on the current when the FET is ON.

Put in a loop with the appropriate (not 100%) hooks to skip pulses at light load :