Since the slope compensation ramp m

Since the slope compensation ramp must be at least half, and preferably equal to the down slope of the currentsense waveform seen at the pulse width modulator, a maximum value is placed on the current sense resistorwhen operating in continuous mode at 50% duty cycle or greater. For design purposes, some margin should beapplied to the actual value of the current sense resistor. As a starting point, the actual resistor chosen should be80% or less that the value calculated in Equation 10. This equation calculates the resistor value that makes theslope compensation ramp equal to one half of the current ramp downslope. Values no more than 80% of thisresult would be acceptable.