The TPS22916B, TPS22916BL, TPS22916C, and TPS22916CL include a Quick Output Discharge feature. When the switch is disabled, a discharge resistor is connected between VOUT and GND. This resistor has a typical value of QOD and prevents the output from floating while the switch is disabled.

As load capacitance and load resistance increase: t_FALL increases. The larger the load resistance or load capacitance is, the longer it takes to discharge the capacitor, resulting in a longer fall time.

The output fall time is determined by how quickly the load capacitance is discharged and can be found using Equation 1 .

Where

• V_10% is 10% of the initial output voltage
• V_90% is 90% of the initial output voltage
• R_DIS is the result of the QOD resistance in parallel with the Load Resistance R_L
• C_L is the load capacitance

With the Quick Output Discharge feature, the QOD resistance is in parallel with R_L. This provides a lower total load resistance as seen from the load capacitance which discharges the capacitance faster resulting in a smaller t_FALL.