The LP2992 is designed specifically to work with ceramic output capacitors, using circuitry that allows the regulator to be stable across the entire range of output current with an output capacitor whose ESR is as low as 5mΩ. Tantalum or film capacitors are available for use at the output, but these capacitors are not as attractive for size and cost reasons.

Make sure the output capacitor meets the requirement for minimum amount of capacitance and also have an ESR value within the stable range. Curves are provided that show the stable ESR range as a function of load current (see Figure 5-59).

Make sure the output capacitor maintains the ESR within the stable region over the full operating temperature range of the application to provide stability.

The legacy chip version of the LP2992 requires a minimum of 4.7µF on the output (increase output capacitor size without limit). Remember to take capacitor tolerance and variation with temperature into consideration when selecting an output capacitor so that the minimum required amount of output capacitance is provided over the full operating temperature range. Ceramic capacitors potentially exhibit large changes in capacitance with temperature.

Do not locate the output capacitor more than 1cm from the output pin. Make sure the output capacitor returns to a clean analog ground.