This figure shows the typical circuit used to set the current limit level.  A positive 10uA current source is internally connected from the voltage-in pin, to the CS negative pin, or the negative input to the current sense comparator. This sets the comparator offset voltage, VSET, across the set resistor, RSET. During operation, VSET is compared to the sense voltage, VS, across the sense capacitor or CS. The equation to calculate RSET is shown in the upper right. ILIMIT, in amps, is the desired current limit level. RDCR is the rated direct current resistance of the inductor, in ohms. ICS negative, in amps, is the positive 10uA current source flowing out of the CS negative pin. ILIMIT should be set sufficiently higher than the peak inductor current at maximum output current to minimize false current limit signals. DCR voltage filter components Rs and Cs should be chosen to match the inductor over DCR resistor time constant (L/RDCR).  A typical range of capacitance used in the RsCs network is 100nF to 1uF. After choosing a CS capacitor, RS can be calculated by the equation in the bottom right. The bypass capacitor across the current sense comparator, or CSBY, is used to filter any noise that may exist across the CS positive and CS negative pins.  A working range for the CSBY capacitance is 47pF to 100pF.