Nope.solve the quadratic below. It should be valid for any Op amp with an open loop gain of 100db and low freq cut off at 10 Hz.
Not quite sure I understand your second remark about the phase margin, so a circuit such as this would not work if built in the lab?
I also did want to mention that the calculations above mean you can work out R and C to produce any Sinewave generator you want from the formula, you just need to know the typical Gain response of the Op-amp you're using. However I can't quite see a way of going in the other direction, i.e looking at a circuit and figuring out it's oscillation frequency from R and C. To rearrange my formula to calculate F, it is still a function of R, C and the Open Loop gain of the Op-amp, which itself is a function of frequency A(f). However, how do you get A(f), when you're looking for F in the first place? Puzzling. You could of course use the values of R and C to define the attenuation of the RC filter response and substitute its reciprocal in for A(f). But again, this is also a function of frequency. Going around in circles a bit!
Megamox
....................... but the cheap LM741 does not even have a minimum slew rate spec.
Nope. The cheap LM741 does not have a minimum slew rate spec.
...wo=SQRT(wT/RC) ...
2*Pi*F(^2)*RC + F - GBW = 0
I know it's probably overkill to go into so much detail for a circuit that will probably not perform anywhere near this frequency in real life, or perhaps not even oscillate at all but I did want to convince myself that in general you were not able to perform a complete description of the oscillation frequency of such an oscillator without including the Op amp as a factor. Perhaps such a device could be used to determine the GBW of various op-amps, by measuring the frequency of the sinewave the circuit puts out?
Megamox
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