Setting the DEF pin to high increases the output voltage of the TPS62150x devices by 5% above the nominal voltage ⁽¹⁾. When DEF is low, the device regulates to the nominal output voltage. Increasing the nominal voltage allows adapting the power supply voltage to the variations of the application hardware. More detailed information on voltage margining using the TPS62150x device is in Voltage Margining Using the TPS62130 Application Report. The pin has an internally connected pulldown resistor of about 400 kΩ to ensure a proper logic level if the pin is high-impedance or floating after an initially low setting. Setting the pin high disconnects the resistor.