Design Support


As current-mode conversion increases in popularity, several peculiarities associated with fixed-frequency, peak-current detecting schemes have surfaced. These include instability above 50% duty cycle, a tendency towards subharmonic oscillation, non-ideal loop response, and an increased sensitivity to noise. This application note attempts to show that the performance of any current-mode converter can be improved and, at the same time, all of the above problems can be reduced or eliminated by adding a fixed amount of "slope compensation" to the sensed-current waveform.