SNVSBK2 September 2019 LP8733
A short-circuit protection feature allows the LP8733xx to protect itself and the external components against a short circuit at the output or against overload during start-up. For the buck and LDO regulators, the fault thresholds are about 350 mV (buck) and 300 mV (LDO). The protection is triggered and the regulator is disabled if the output voltage is below the threshold level (1 ms) after the regulator is enabled.
In a similar way, the overload situation is protected during normal operation. If the output voltage falls below 0.35 V and 0.3 V and remains below the threshold level for 1 ms, then the regulator is disabled.
In Buck regulator short-circuit and overload situations, the BUCKx_SC_INT bit in the INT_BUCK register and the INT_BUCKx bit in the INT_TOP_1 register are set to 1, the BUCKx_STAT bit in BUCK_STAT register is set to 0, and the nINT signal is pulled low. In LDO regulator short-circuit and overload situations, the LDOx_SC_INT bit in the INT_LDO register and the INT_LDOx bit in the INT_TOP_1 register are set to 1, the LDOx_STAT bit in the LDO_STAT register is set to 0, and the nINT signal is pulled low. The host processor clears the interrupt by writing 1 to the BUCKx_SC_INT or to the LDOx_SC_INT bit. Upon clearing the interrupt, the regulator makes a new start-up attempt if the regulator is in an enabled state.