The active discharge function uses an internal MOSFET that connects a resistor (R_PULLDOWN) to ground when the LDO is disabled in order to actively discharge the output voltage. The active discharge circuit is activated by driving EN to logic low to disable the device, when the voltage at IN or BIAS is below the UVLO threshold, or when the regulator is in thermal shutdown.

The discharge time after disabling the device depends on the output capacitance (C_OUT) and the load resistance (R_L) in parallel with the pulldown resistor.

Do not rely on the active discharge circuit for discharging a large amount of output capacitance after the input supply has collapsed because reverse current can flow from the output to the input. This reverse current flow can cause damage to the device. Limit reverse current to no more than 5% of the rated output current for a short period of time.