The supply undervoltage and overvoltage thresholds are set using the resistors R1, R2 and R3 whose values can be calculated using Equation 10 and Equation 11:

Where V_UVLO(R) is the UVLO rising threshold and V_OV(R) is the OVLO rising threshold. Because R1, R2 and R3 leak the current from input supply V_IN, these resistors must be selected based on the acceptable leakage current from input power supply V_IN. The current drawn by R1, R2 and R3 from the power supply is IR123 = V_IN / (R1 + R2 + R3). However, leakage currents due to external active components connected to the resistor string can add error to these calculations. So, the resistor string current, IR123 must be chosen to be 20 times greater than the leakage current expected on the EN/UVLO and OVLO pins.

From the device electrical specifications, both the EN/UVLO and OVLO leakage currents are 0.1 μA (maximum), V_OV(R) = 1.2 V and V_UVLO(R) = 1.2 V. From design requirements, V_IN(OV) = 13.2 V and V_IN(UV) = 10.8 V. To solve the equation, first choose the value of R1 = 470 kΩ and use the above equations to solve for R2 = 10.7 kΩ and R3 = 48 kΩ.

Using the closest standard 1% resistor values, we get R1 = 470 kΩ, R2 = 11 kΩ, and R3 = 47 kΩ.