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I am working on a AK5578 ADC, and the datasheet gives the following example for an input buffer :
I can't figure out the usefulness of the 10 ohm resistor on output of both opamps. Are they for limiting the output current in case of a short circuit ? And in that case, can I replace the NJM5534 by an opamp that can sustain unlimited output short circuit (MC33078) and get rid of these resistors ?
Most likely this resistor is there to increase the stability of the operational amplifier.
Looking at the datasheet it can be seen that a compensation capacitor is used for a load of 100pF. (The 1nF capacitor can be ignored as a current is fed back through it.)
In this application no compensation capacitor is used, therefore a resistor is placed in series to improve stability.
Those 10 ohm resistors are put there to work in conjunction with the 100pF capacitors to GND as an RC filter.
Note that some opamps are also not stable with much of any capacitive load and the 10 ohm resistors can help with that as well.
