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comparator/integrator triangle wave oscillator help?

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Michael Circuit

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I have tried this circuit with a TL072 dual op amp about a dozen times on my breadboard now I would like to generate a 10khz triangle wave. Im obviously not doing this right, although the circuit is so simple, what could i possibly be missing?
Rt= 3.54k
R1= 10k
R2= 33k
c1= 0.01uf
 
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Are you using dual, split supplies on the opamps?

What opamps?
 
I am using a TL072 dual op amp, ive tried several different voltages from 5-9 volts in.

Ok, but you never tried TWO power Supplies connected in series, with say +9V connected to the VCC pin of the opamps, -9V connected to the Vss pin, and the tap between the two supplies connected to Ground, right?

That is what it will take to make the published circuit work. Every time you see an opamp symbol shown in a circuit with no power supply shown, you should automatically think SPLIT supplies.

Let me anticipate your next question: "How do I make it run on ONE power supply?"

Start by studying the first post in this thread.
 
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after reading the link you provided https://www.electro-tech-online.com/custompdfs/2011/02/sloa058.pdf what you are saying is the inverting input (-) of the comparator or first opamp and the non inverting input (+) of the integrator or second opamp are not actually connected to ground? Instead according to the link provided they are connected to a "virtual ground" which is Vcc/2 or one half the Vin of the IC? so If my +Vin is +10volts, my virtual ground would need enough resistance to allow only +5v in? why would they use the "ground" symbol in the schematics if this is not actually what is required?
 
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No, the ground symbol is GROUND!!!! What is missing in your implementation of the circuit is the NEGATIVE power supply.

I say again: "Every time you see an opamp symbol in a circuit with no power supply pins shown, you should automatically think SPLIT supplies."

If you are bound and determined to run this circuit on a SINGLE power supply, you will have to create a HALF-Supply floating reference voltage as shown in FIG 2 of the APP NOTE. Because the HALF node goes only to two inputs of two opamps, you do not need to buffer it with a opamp connected as a voltage follower. The bypass cap is a good idea, however.
 
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Fig 1 is how to make a triangle wave with a single supply:

Fig 2 is how to make a triangle wave with split supplies:

Fig 3 is a simplified oscillator that runs on a single supply:
 

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