Run simulation(s) aborted

[duchx]

Hi,

simple diagram

when I turn on the simulations I have an error:

Circuit: KiCad schematic
Background thread stopped with timeout = 0
Doing analysis at TEMP = 27,000000 and TNOM = 27,000000
Fatal error: tp1: transmission line z0 must be given
doAnalyses: no such parameter on this device
run simulation(s) aborted

I’ve been struggling with this for several hours and can’t find anything on google

I also noticed that when I try to add a probe from the spice simulator level, you cannot add this probe in the diagram

help.

[gkeeth]

The issue is the TP1 symbol which spice doesn’t understand how to simulate correctly.

It is getting added to the SPICE netlist as TP1 <some other parameters>

ngspice will interpret any device that starts with “T” as a transmission line (see http://ngspice.sourceforge.net/docs/ngspice-html-manual/manual.xhtml#magicparlabel-5923), just like it will interpret “R” as resistor, “C” as capacitor, “L” as inductor, “V” as voltage source, etc.

In this case, it is complaining that TP1, which it thinks is a transmission line, does not have the appropriate parameters for a transmission line given (namely, your testpoint/transmission line does not specify a characteristic impedance z0).

The solution to your issue is to tell kicad that TP1 should be ignored for simulation, so ngspice will not attempt to simulate it. It doesn’t make sense to simulate a testpoint anyway – I’m not sure where that symbol is from but the testpoint symbols in the standard library are intended to represent physical testpoints on a pcb. In 5.99, the way to accomplish this is to go to the symbol properties -> Spice model… -> check “Disable symbol for simulation”. I don’t remember offhand the way to do this in 5.1 but I’m sure it’s similar.

In general, you’ll need to specify a spice model for every symbol in the schematic, or disable it for simulation if it’s irrelevant.

With regard to your question about adding a probe from the simulator, it sounds like you’re coming from a spice simulator that lets you add probes as persistent symbols in the schematic (Multisim?). As far as I know, you can’t do that with kicad/ngspice. You’ll need to either add the symbols each time you launch the simulator. You can also save your simulator setup as a workbook and restore it later – not sure what the limitations are with this as I haven’t played with it much.

[duchx]

Hi, at the beginning I would like to thank you for your answer.

I changed TP1 to PCB1

please tell me what to enter in the value position?

[gkeeth]

If you have disabled the symbol for simulation, it shouldn’t matter what the value is.

For that, click the button to the left of “OK” (Spice Model) and check the box “Disable symbol for simulation”

[duchx]

thank you, it works.

Circuit: KiCad schematic
Doing analysis at TEMP = 27,000000 and TNOM = 27,000000
Warning: v1: no DC value, transient time 0 value used
Reference value : 1,00000e+02
No. of Data Rows : 41

can you still tell me why it doesn’t show square signal?

starting frequency 100 Hz
100,000 Hz final frequency

[gkeeth]

You’re doing an AC simulation, which gives you magnitude and phase vs. frequency.

It sounds like you want a transient simulation, which gives you voltage or current versus time.

You’ll need to switch the simulation type to transient.

There is an example of a transient simulation in section 3 here: http://ngspice.sourceforge.net/ngspice-eeschema.html

[duchx]

Thank you very much for help