The TPS25948xx allows the user to implement Overvoltage protection on the bus to shield the system against supply overvoltage conditions. The internal fast comparator on the OVLO pin allows the Overvoltage Lockout threshold to be adjusted to a user defined value. Once the voltage at the OVLO pin crosses the OVLO rising threshold V_OV(R), the device turns off both the FETs to cut off the power path. Thereafter, the devices wait for the voltage at the OVLO pin to fall below the OVLO falling threshold V_OV(F) before the FETs are turned ON again. The rising and falling thresholds are slightly different to provide hysterisis. Figure 7-5 and Equation 2 show how a resistor divider can be used to set the OVLO set point for a given voltage supply.

While recovering from a OVLO event, the TPS25948xx bypasses the inrush control (dVdt) and starts up in a current limited manner to provide faster turn ON and minimize power supply droop during supply transient conditions.