The TLV70018-Q1 and TLV70012-Q1 internal current limit helps to protect the regulator during fault conditions. During current limit, the output sources a fixed amount of current that is largely independent of the output voltage. In such a case, the output voltage is not regulated, and is V_OUT = I_LIMIT × R_LOAD. The PMOS pass transistor dissipates (V_IN – V_OUT) × I_LIMIT until thermal shutdown is triggered and the device turns off. As the device cools, it is turned on by the internal thermal shutdown circuit. If the fault condition continues, the device cycles between current limit and thermal shutdown. See the Thermal Considerations section for more details.

The PMOS pass transistor in the TLV70018-Q1 and TLV70012-Q1 has a built-in body diode that conducts current when the voltage at OUT exceeds the voltage at IN. This current is not limited, so if extended reverse voltage operation is anticipated, external limiting to 5% of the rated output current is recommended.