For the TLV3603(E), the hysteresis vs. resistance curve (Figure 8-2) can be used as a guidance to set the desired amount of hysteresis. Figure 8-2 shows that for a 30-mV hysteresis, a 150 kΩ resistor must be placed from the LE/HYS pin to VEE.

For the TLV3601 and TLV3602, the following procedure can be used to add external hysteresis for a non-inverting configuration. Note that V_HYST << V_REF, so V_HYST can be ignored and is not included in the following equations for simpler calculation.

The equivalent resistor networks when the output is high and low are shown in Figure 8-7.

Figure 8-7 Equivalent Resistor Networks for Non-Inverting Configuration with Hysteresis.

When V_IN is less than V_REF, the output is low. For the output to switch from low to high, V_IN must rise above the V_H threshold. Use Equation 1 to calculate V_H.

When V_IN is greater than V_REF, the output is high. For the comparator to switch back to a low state, V_IN must drop below the V_L threshold. Use Equation 2 to calculate V_L.

The hysteresis of this circuit is the difference between V_H and V_L, as shown in Equation 3.

Select a value for R2. Plug in given values for V_CC, V_REF, V_H, and V_L. For the given example, R2 = 10 kΩ, and R1 is solved as 60 Ω.

For more information, please see Application Notes SNOA997 "Inverting Comparator with Hysteresis Circuit", SBOA313 "Non-Inverting Comparator With Hysteresis Circuit", SBOA219 "Comparator with and without hysteresis circuit".