From: Clifford W. <cli...@cl...> - 2007-12-25 18:02:54
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Hi, On Tue, Dec 25, 2007 at 06:47:14PM +0100, Bastien ROUCARIES wrote: > > ERROR: TR1: Jacobian singular at t = 6.531e-02, > > aborting transient analysis > > > > I have to admit that I don't know anything about the math behind this > > simulations, so I can't tell whats going on here. > > > > Depending on resistor and capacitor values this message pops up earlier or > > later. > > Add a small resistor vin serie with capacitor. It is a classical mistake in > this kind of circuit to not put dissipative element. If you do not put > dissipative element slope is too high for good simulation and you will get > divide by zero. I've added 50 Ohm resistors in series with my capacitors and now I do get: ERROR: TR1: Jacobian singular at t = nan, aborting transient analysis t = nan ??? looking at the data generated by the simulation it should be something like t = 0.007. I also don't think that this should make much of a difference.. or am I wrong when I assume that the BC549 model always has at least some B-E resistence? So even if there is no C-E resistance (which I woukd consider a bug in the device model), the capacitors would never be discharged or charged without a load-resistor.. yours, - clifford -- [..] If it still doesn't work, re-write it in assembler. This won't fix the bug, but it will make sure no one else finds it and makes you look bad. |