Alberto,
I am just starting to play with this simulation tool and have a basic
question. I modeled a
simple oscillator, with a 2N2222 and some passive components. If I simulate
it with Electronics >Workbench it happily oscillates. With PSpice it
doesn't, no matter how I change the feedback.
I suspect that some noise source should be added to trigger the
oscillation, but don't know how, >nor I am sure that this is indeed true.
Not sure what the secrete is to getting your oscillator to start. Are you
using the Vcc as power supply? There has to be some kind of transient to get
them to start. I've simulated a few oscillators over a year ago but can't
remember having problems. I'll try the 2N2222 in a simple Colpits circuit
when I find a spare moment and will get back to you.
There are two great workbooks on Psice simulations by Roy W. Goody. The
Title for both is 'MicroSim Pspice for Windows', copyright date 1998. Volume
II is the one that covers oscillators. Check this tile on the various Web
sites for used books and you might find a real bargain.
Good luck!
Bill A
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