The ISENSE Pin senses the voltage drop at theexternal sense resistor (RSHUNT). This is the input signalfor the average current regulation in the current loop. Itis also fed to the peak current limitation block.During power up time, high inrush currents cause highnegative voltage drop at RSHUNT, driving currents out ofpin 2 which could be beyond the absolute maximumratings. Therefore a series resistor (RCS) of around 50Ωis recommended in order to limit this current into the IC.