Spicing Colpitt osc?
Spicing Colpitt osc?
(OP)
I am trying to simulate a crystal Colpit oscillator in the free B2-Spice edition. (release 4.2.1)
I do have oscillation, but only a few mVpp, and only very near a perfect sine. (No harmonics it seems
The crystal is composed of 20fF, 1.25mH and 30 Ohm resistor in series. All shunted by 4.5pF. (Roughly 30MHz.)
These parameters seem to be in the correct area if compared to various ex. out on the web.
I have tried other oscillator circuits, but more or less with same results.
If I instead change the series LC parts a factor of 1,000 (down in impedance) I get a nice Colpitt waveform of more than 1 Vpp
Is it my model or is it Spice, that is incorrect?
I do have oscillation, but only a few mVpp, and only very near a perfect sine. (No harmonics it seems
The crystal is composed of 20fF, 1.25mH and 30 Ohm resistor in series. All shunted by 4.5pF. (Roughly 30MHz.)
These parameters seem to be in the correct area if compared to various ex. out on the web.
I have tried other oscillator circuits, but more or less with same results.
If I instead change the series LC parts a factor of 1,000 (down in impedance) I get a nice Colpitt waveform of more than 1 Vpp
Is it my model or is it Spice, that is incorrect?





RE: Spicing Colpitt osc?
1) The model does not accurately represent the real-world item.
2) The simulator does not take all necessary real-world variables into account.
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Spicing Colpitt osc?
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RE: Spicing Colpitt osc?