As with most LDOs, this device can be damaged by excessive reverse current.

Reverse current is current that flows through the body diode on the pass element instead of the normal conducting channel. This current flow, at high enough magnitudes, degrades long-term reliability of the device resulting from risks of electro-migration and excess heat being dissipated across the device. If the current flow gets high enough, a latch-up condition can be entered.

Conditions where excessive reverse current can occur are outlined in this section, all of which can exceed the absolute maximum rating of V_OUT > V_IN + 0.3 V:

• If the device has a large C_OUT and the input supply collapses quickly with little or no load current
• The output is biased when the input supply is not established
• The output is biased above the input supply

If excessive reverse current flow is expected in the application, then external protection must be used to protect the device. Figure 9-13 shows one approach of protecting the device.

Figure 9-13 Example Circuit for Reverse Current Protection Using a Schottky Diode