SLUSCZ1 May 2017 TPS92518-Q1
PRODUCTION DATA.
If drop-out operation is not desired, configure a resistor divider to disable switching of both channels at the desired input voltage.
The value of resistors R2 and R3 establish the undervoltage lockout level as shown in Figure 31. Include a small level of capacitance (approximately 0.1 μF) at the UVLO pin for noise immunity. If the application does not require drop-out operation (operation when VVIN approximates VVLEDx) program a UVLO level that allows no switching to occur until there is adequate input voltage available.
Select the desired amount of voltage hysteresis and the desired turn-ON threshold (VIN-RISE_THRESHOLD). Because of the small amount of fixed-voltage hysteresis and fixed-hysteresis current, some combinations of turn-ON and turn-OFF thresholds are not possible. If the calculation results in values that are zero or negative, the combinations selected are not possible. After selecting a turn-ON point and desired amount of voltage hysteresis (VHYST) use Equation 26 and Equation 27 to calculate R3 and R2.