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ADP7142 linear regulator, output capacitor ESR

Category: Datasheet/Specs
Product Number: ADP7142

Hello experts,

The datasheet for the ADP7142 linear regulator recommends a minimum 2.2uF output capacitor with ESR<0.3 ohm (see pages 4 and 14):  "The ESR of the output capacitor affects the stability of the LDO control loop. A minimum of 2.2 µF capacitance with an ESR of 0.3 Ω or less is recommended to ensure the stability of the ADP7142."

The evaluation board for the ADP7142 uses a 4.7uF 50V Samsung CL31B475KBHNNNE.  This has a sufficiently low ESR down to about 10kHz, but the ESR then rises rapidly to about 4 ohms at 100Hz (see data tool, double-click capacitor entry and click R to plot ESR).

I am intending to feed my ADP7142 with a linear supply which will have some minor 100Hz content (and harmonics).  Do I need to use a capacitor with lower ESR at 100Hz, or is the stability issue only an issue with higher frequencies?

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