Low-Cost Alternative to a Function Generator: The Bubba Oscillator by Phillip Johnston. 4 March Introduction. When testing the functionality of a circuit or . 12 Feb Hi guys, I simulated a bubba oscillator, but the circuit output is 6Vdc, it don’t oscillate. Can you help me? Pspice frequency = 60hz The. Solved: Hi there. I’m trying to make a sine wave inverter based on “Bubba Oscillator”. The output of the bubba oscillator is a nice sine.

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This is not that easy to model I know, I have tried.

Sign up using Email and Password. No I do mean finite gain opamps, but try it and see if it helps, it won’t.

bubba oscillator

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The amplitude bybba exponentially. Post as a guest Name.

Your misconception comes from the fact that you first have to understand the theory of operation of oscillators. So the solution to your problem is: Surprisingly, such a “hard-limiting” will cause only a slight distortion because the loop will adjust itself to a loop gain of unity. Zoomed result Simulated for 10sec: It has started to oscillate.


This is not a good solution if you need low distortion sinewave. Sorry, i am quite new at electronics The problem is that i am not able to generate the sinusoidal from the circuit.

A good analog sinewave oscillator has a specially designed contol circuit which checks the output amplitude and reduces the gain until output oxcillator is the wanted. That’s what your plot shows. Insert that limiting circuit in parallel with one of the capacitors. Sign up using Odcillator.

That would be gr By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service. What happens after that I have seen in practical circuits even a NTC resistor used here. Here’s the output from LTSpice: This below is my circuit: Such an oscillator with real opamps will stabilise its signal amplitude on the point where the loopgain is precisely one. What you see is the oscilator starting.

And this below is my result Simulated for 10sec: And that means the loopgain becomes smaller. By clicking “Post Your Answer”, you acknowledge that you have read our updated terms of serviceprivacy policy and cookie policyand that your continued use of the website is subject to these policies.

In the article about the Bubba oscillator the author uses real opamps. However when the loopgain remains higher than 1 the amplitude of the oscillation will increase and keep increasing. This states that an oscillator oscillates when the loopgain is more than 1.


Bubba Oscillator – CircuitLab

This effect cannot be found in the literature. By real op-ampsdo you mean finite gain op-amp? Home Questions Tags Users Unanswered. A drastic improvement reduction of distortion is possible when we use two different supply rail voltage pairs and when the ouput is taken from the block with the larger supply voltage limiting effect in the block with smaller supply voltages.

What is needed is a limitation on the output voltage. Better would be to use a tanh x like function so that it limits but in a continous way. I have the design file I can upload.

Take a couple of zener diodes connected in series having the anodes against each other. Bimpelrekkie – that is not the odcillator. But this will probably result in a distorted sinewave.

bubba oscillator | All About Circuits

These opamps cannot generate infinite voltages so at some voltage their output voltage will be less than what you would ideally expect. In control theory they call it PI controller. The controller searches the right gain continuously but has proper inertia which prevents the distortion of the sine pulses.