Some applications can have transients that place this device into dropout, especially when this device can be powered from a battery with relatively high ESR. The load transient saturates the output stage of the error amplifier when the pass transistor is driven fully on, making the pass transistor function like a resistor from V_IN to V_OUT. The error amplifier response time to this load transient is extended because the error amplifier must first recover from saturation and then must place the pass transistor back into active mode. During this recovery period, V_OUT overshoots because the pass transistor is functioning as a resistor from V_IN to V_OUT.

When V_IN ramps up slowly for start up, the slow ramp-up voltage can place the device in dropout. As with many other LDOs, the output can overshoot on recovery from this condition. However, this condition is easily avoided through the use of the enable signal.

If operating under these conditions, apply a higher dc load current or increase the output capacitance to reduce the overshoot. These approaches provide a path to absorb the excess charge.