He wants the equivalent of a bar graph, 20 values on a single signal.
Using 20 frequency sources each could be multiplied by the related signal to be displayed and the outputs combined to produce 20 peaks in a spectral output. A bit messier than a signal with DC levels, but not horribly so.
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Fred Bloggs
Good luck figuring anything out from that Help file gibberish.
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Jasen Betts
you could just use a bunch of switches each with a different non-overlapping on time, they can be as ideal as you want.
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jlarkin
The native Help is pretty bad, but there are tons of web sites that are good.
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legg
This topic on the LTspice forum may be addressing your 'challenge':
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RL
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jlarkin
Interesting, but that's not what I want to do.
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legg
Not sure I see it.
Do you want a visual display similar to a bar spectrun analyser output?
RL
RL
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jlarkin
I've explained it. X-axis is node number. Y axis is voltage on each of those nodes. Since node numbers are discrete, it would probably look stairstepped, like a DAC output.
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Rich S
Ah, maybe... Is this it? I took 20 sample-and-holds. Each 'sample' pin driven by its own timed pulse. The 20 pulses are a time series, generated by a stimulus generator (actually 3 16-bit generators, just using the first 20 of 48 outputs). I setup the stimulus pattern to toggle each 's' node ('sample') every 1us, followed by 1us logic-low , then 1us 'reset', 1us of logic-low, etc. The work was a bit tedious but not too bad.
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Rick C
I'll let you whitewash this fence if you give me your apple! "Work consists of whatever a body is obliged to do, and that Play consists of whatever a body is not obliged to do".
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legg
All this talk about how LTspice encourages your instincts;
....and here you are wanting to load the poor circuit with twenty voltmeters.
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jlarkin
In this case, that graph is what I want to train my instincts.
Spice doesn't care about loading. I sometimes have to force myself to not care about kilowatt resistor power dissipation, or megavolt potentials.
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Bob Baylor
I would use python. The script could present a GUI of the output and any input control of the circuit (values, voltages, frequencies, whatever). Spice can be pretty slow, of course, so the GUI controls wouldn't be "live"; Instead, there would be a "Do it" button to start the cycle: * write a file of parameter values for inclusion into the spice model * run Spice * process the raw file using the ltspice python library * plot the nodes of interest. If you're trying to get a "feel" for the transfer functions, plot little trails of the previous runs.
I had a project that required LTSpice to verilog test vectors to Vivado to vcd dump files (vddvcd python library) to final processing (to verify the verilog). The GUI would probably take the most time to code. Perhaps just columns of numbers would be ok?
HTH, Bob
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invalid unparseable
Rotate your laptop 90 degs.
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SuperSpice
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