Simulating Oscillator Noise

(Note, transient noise is NOT recommended for oscillators)

Useful resource:

Performing Oscillator Noise Simulation in Spectre RF (on COS)

 

Why is it called “Beat Frequency”? Why is video showing 1.9G?

When I launch form, both BF and Number of Harmonics are blank

BL: You have to enter both. Set known frequency of oscillation for BF and 15 for number of harmonics.

For an oscillator, always set Conservative

Setting “Decide automatically” causes TSTAB to run ideal steady-state till it is achieved and then switch to the “Shooting” phase automatically.

Only set Save Initial Transient Results if you are interested in that startup waveform.

Leave “Oscillator node-“ blank even for a differential oscillator!

Then, click Apply and move to the pnoise form by checking that button at the top of the form

 

Max sidebands should be set to same value as Number of Harmonics on the PSS form.

Unlike with PSS, for the PNOISE form, both nodes of a differential oscillator must be specified!

 

 

 


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