--- In LTspice@..., "beaudoin.christopher" <beaudoin.christopher@...> wrote:
I am modelling a voltage noise source by defining the noise source with a PWL file. The circuit is very basic (two resistors no L's or C's) and I have setup a transient analysis using the time step equal to the time increment in the PWL file. In doing this, what I am finding is that the transient analysis is somehow modifying the statistics(I'm guessing by integration/interpolation)of the random signal defined in the PWL file. For this reason, I'd like to gain a better understanding of what this transient analysis is doing in this very simple case. For example, are there are time constants implicit to the solver that I should be aware of such that I should not expect to achieve a steady state case until some time "Tsteadystate" even if there are no Ls or Cs in the circuit? Any understanding you can offer would be greatly appreciated.
Best Regards,
Chris
Hello Chris,
LTspice dynamically changes the time step. You should simply
a small maximum time step in the .TRAN command. This ensures
that nothing will be lost. LTspice does a linear interpolation
between your defined PWL data points.
LTspice uses data compression by default when it saves the
results of the simulation. If you you want the best result,
you should disable data compression in this case. Please add
the following SPICE-directive to your schematic. It will
switch off data compression.
.options plotwinsize=0
Best regards,
Helmut
