[Moved] bubba oscillator proteus simulation is not showing output

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rohitdevdhar

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hi friends.
i made a proteus simulation of bubba oscillator. but the simulation is not showing output.
please help.
 

1) You must learn about how to bias an opamp. You have pin 3 at the supply voltage of 5V but the datasheet says an input of an LT1014 opamp does not work if it is higher than 3.5V when there is a 5V supply. Pin 3 should be at half the supply voltage (Texas Instruments was wrong in their text that I deleted).

2) You have its AC and DC gain at more than 4 thousand times but it must be a little more than only 4 in a Bubba oscillator.

3) The input resistance of the LT1014 opamp is too low to use a feedback resistor as high as 2.2M ohms.

4) Your value of only 470 ohms for R6 shorts the signal.

5) Also usually an oscillator in a simulation needs to be kicked with a pulse to get it going.

Here is the Bubba oscillator from Texas Instruments that is using a modern rail-to-rail input and output quad opamp that has an extremely high input resistance:
 

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