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Will the LT1129-5 output be stable with ceramic output capacitors?

The datasheet says ESR should be less than 2ohms, with no defined minimum, but also shows the use of a tantalum in the suggested circuit. Other regulators explicitly say whether it is suitable for use with ceramic output capacitors, but this ones does not. I am looking for a drop-in replacement for an unavailable TI part, an LM2937IMP-5.0, and otherwise this part looks suitable.

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  • The datasheet text says there is no minimum for the ESR of COUT as long as the minimum capacitance requirement is met.  I show the datasheet text in the image below.  Just to be safe, make sure you account for the DC bias effect on capacitance characteristic of the ceramic capacitor you choose.  I am guessing that it was common during the LT1129's era to use electrolytic capacitors in example applications rather than ceramics, but that was not to imply that ceramics would not work.

    LT1129 COUT_1.png

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  • The datasheet text says there is no minimum for the ESR of COUT as long as the minimum capacitance requirement is met.  I show the datasheet text in the image below.  Just to be safe, make sure you account for the DC bias effect on capacitance characteristic of the ceramic capacitor you choose.  I am guessing that it was common during the LT1129's era to use electrolytic capacitors in example applications rather than ceramics, but that was not to imply that ceramics would not work.

    LT1129 COUT_1.png

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