During normal operation the high-side and low-side MOSFET switches are protected by its current limits I_LIMF. Once the high-side MOSFET switch reaches its current limit, it is turned off and the low-side MOSFET switch is turned on. The high-side MOSFET switch can only turn on again, once the current in the low-side MOSFET switch decreases below its current limit I_LIMF. The device is capable to provide peak inductor currents up to its internal current limit_ILIMF..

As soon as the switch current limits are hit and the output voltage falls below 1/3 of the nominal output voltage due to overload or short circuit condition, the foldback current limit is enabled. In this case the switch current limit is reduced to 1/3 of the nominal value I_LIMF.

Due to the short circuit protection is enabled during start-up, the device does not deliver more than 1/3 of its nominal current limit I_LIMF until the output voltage exceeds 1/3 of the nominal output voltage. This needs to be considered when a load is connected to the output of the converter, which acts as a current sink.