Resistors R1 and R2 connected in series is used to program the overvoltage threshold. Connecting R1 to VIN provides overvoltage cutoff and switching the connection to VOUT provides overvoltage clamp response. The resistor values required for setting the overvoltage threshold VOV to 37 V are calculated by solving Equation 3
Equation 3.
For minimizing the input current drawn from the supply through resistors R1 and R2, it is recommended to use higher value of resistance. Using high value resistors adds error in the calculations because the current through the resistors at higher value becomes comparable to the leakage current into the OV pin. Select (R1 + R2) such that current through resistors is around 100 times higher than the leakage through OV pin. Based on the device electrical characteristics, VOVR is 1.25 V , Select (R1) = 100 kΩ and R2 = 3.5 kΩ as a standard resistor value to set overvoltage cutoff of 37 V.