ZHCS840G February 2012 – February 2019 TPS3700
Select a value for RT such that the current through the divider is approximately 100 times higher than the input current at the INA+ and INB– terminals. The resistors can have high values to minimize current consumption as a result of low-input bias current without adding significant error to the resistive divider. See the application note Optimizing Resistor Dividers at a Comparator Input (SLVA450) for details on sizing input resistors.
Use Equation 2 to calculate the value of R3.
The worst-case tolerance can be calculated by referring to Equation 13 in application report SLVA450, Optimizing Resistor Dividers at a Comparator Input (available for download at www.ti.com). An example of the rising threshold error, VMON(OV), is given in Equation 5.