Tool/software:
Part: LP2951CMX/NOPB
What is the best practice for increasing the ESR of output capacitors in LDOs?
Often, multiple output capacitors are used in parallel because each chip that requires the LDO's output voltage also needs its own output capacitor. Therefore, adding a separate resistor for each output capacitor is not practical.
At the same time, the design should remain stable with future capacitors that may have significantly lower ESR than those used today.
For this reason, we want to add a resistor to ensure the LDO remains stable regardless of the specific output capacitors used.
What is the recommended best practice for adding this resistor?
In the schematic below, R4 increases the voltage drop under load. However, this is tolerable in most applications. Is this sufficient to ensure stability?
To improve this behaviour, it might be possible to place the resistor before the feedback pin. Would the solution using R3 still improve stability in this case?
Thank you for your help!
