if i have the following circuit , what the expected behaviour of the following caps ? , it will be charge and discharge very quickly since we have a low inpedance form op-amp?
simulate this circuit – Schematic created using CircuitLab
Op-amp and capacitor 2
capacitoroperational-amplifier
Best Answer
I expect this will oscillate or otherwise not behave as you intend. The TL081 is supposedly unity gain stable, but it is unlikely stable at unity gain and with such a large capacitive load.
Even if the opamp were ideal, your circuit doesn't make sense. A perfect ideal opamp would drive its output to whatever it takes. The cap would just cause lots of current whenever it changes its output voltage.
If your intent is to low pass filter the output, put a resistor in series with the opamp output before the cap. A better answer for a low pass filter using these components is to put the resistor followed by cap to groun on the input of the opamp.