A problem in VCO Simulation

[xiaofeixia]

Now I'm designing a ring oscillator. when I do the simulation, it need some initial conditions, such as give a initial voltage to the output nodes, or it can not oscillate. I don't know why.Is there any effect to the chip test? Thank you very much!

 

[ustcjin]

Yes, in transient simulation, you need to give initial condition to internal nodes of ring oscillator so that it can oscillate, but in reality, the ring oscillator can amplify its internal noise and finally oscillate. You don't need to worry about the chip test.

 

[xiaofeixia]

I know. Thank you very much!