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Can anyone please tell why my op-amp oscillator is not working here? https://www.circuitlab.com/circuit/7zdp5f/oscillator-circuit/

Hi, It works. Try time 2 s and increment 0.01 s.

May be R1 and R2 too small try 2K2

Yeyy ... It works. Thank you very much. Can you please tell me why initially there is a non-oscillating region?

@go2chayan,

I did not see your original circuit (you have edited it since first posting so the circuit in your link has now changed) but I think @ggennai has hit upon one of the reasons your circuit did not simulate.

Setting the right Time Step size is very important to get a realistic simulation and setting the right Stop Time is also important so that you run the sim for long enough for it to start up and/or reach a steady state.

See:

https://www.circuitlab.com/circuit/d4qjc5/relaxation-osc-fixed-01/

for more background.

However, in many astable and oscillator circuits, the circuit has to be given an initial kick to get it started or to speed up the startup.

Unlike mature spice simulators, CL does not yet allow a sim to be plotted from an arbitrary time after T=0 so if you need a long time for a circuit to start up or settle and a small time step to get the detail right you end up waiting ages for the sim to complete and then the little bit you may actually be interested in is lost in a huge plot so you have to wait ages again for the zoom to sort itself out.

Have a read through some of the examples in:

https://www.circuitlab.com/browse/by-tag/initial-conditions/

https://www.circuitlab.com/browse/by-tag/startup/

and:

https://www.circuitlab.com/circuit/b24363/ramped-and-glitched-signals-and-supplies-01/