LTspice timestep error message meaning

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analog_match

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I am getting the following message in LTspice. I tried incressing the trtol value but nothing seems to help. Does anyone know what this means.

Heightened Def Con from 0.00514743
++++++++++++++++++++++++++++++++++++++++++++++++++Fatal Error: Analysis: Time
step too small; time = 0.00514743, timestep = 1.25855e-018: trouble with
d-instance d3

Thanks
 

It can happen when you run a simulation for a very long time for something which needs very small steps. Try reducing the minimum timestep. I am not sure how you do that on LTspice.

Keith.

Added after 4 minutes:

It might be useful to see your circuit - it can sometimes be a circuit problem.

Keith.
 

Thanks Keith for your reply. I am attaching the circuit schematic here. The CCM-DCM1 block is a linearized model of the switching network that has the following form:

.subckt CCM-DCM1 1 2 3 4 5
+ params: L=100u fs=1E5
Et 1 2 value={(1-v(u))*v(3,4)/v(u)}
Gd 4 3 value={(1-v(u))*i(Et)/v(u)}
* Ga 0 a value={MAX(i(Et),0)}
Ga 0 a value={i(Et)}
Va a b
Ra b 0 10k
Eu u 0 table {v(5)*v(5)/(v(5)*v(5)+2*L*fs*i(Va)/v(3,4))}(0 0) (1 1)
.ends

If you can provide any hints I'd greatly appreciate.
 

Could you send me the full netlist. Use private email if you prefer. I would like to run it through my simulator. If I get the same error I stand a better chance of finding the cause.

Keith.
 

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