The TPS25990 has an integrated output discharge function which discharges the capacitors on the OUT pin using an internal constant current (I_QOD) sink path to GND. The output discharge function is activated when the EN/UVLO is held low (V_SD(F) < V_EN < V_UVLO(F)) for a minimum interval (t_QOD). The output discharge function helps to rapidly remove the residual charge left on large output capacitors and prevents the bus from staying at some undefined voltage for extended periods of time. The output discharge is disengaged when V_OUT < V_FB or if the device detects a fault.

The output discharge function can result in excessive power dissipation inside the device leading to an increase in junction temperature (T_J). The output discharge is disabled if the junction temperature (T_J) crosses the device overtemperature threshold (TSD) to avoid long-term degradation of the part.