The device has a fixed, cycle-by-cycle negative current limit. Similar with the positive overcurrent limit, the inductor current is monitored during the on-time of the low-side FET. To prevent too large negative current flowing through low-side FET, when the low-side FET detects a –10-A current (typical threshold), the device turns off low-side FET and then turns on the high-side FET for a proper on-time (determined by V_IN/V_O/f_SW). After the high-side FET on-time expires, the low-side FET turns on again.

The device must not trigger the –10-A negative current limit threshold during nominal operation, unless a small inductor value that is too small is chosen or the inductor becomes saturated. This negative current limit is utilized to discharge output capacitors during an output OVP or an OOB event. See Section 7.3.12 and Section 7.3.13 for details.