I have installed the old (17.0.36.0) and the new (17.1.6) version of LT on two PCs.
For both versions, I updated the components before the tests.
The difference between 'Test_BW' and 'Test_BW_Time' is a reduced TimeStep.
The criterion of the tests was the representation of the waveform of Vout.
For both versions, I updated the components before the tests.
The difference between 'Test_BW' and 'Test_BW_Time' is a reduced TimeStep.
The criterion of the tests was the representation of the waveform of Vout.
| i3-6350 3.90 GHz Win10 V22H2 | LTspice Version 17.0.36.0 | LTspice Version 17.1.6 |
| Test.asc | ok | ok |
| Test_BW.asc | takes forever, canceled | ok |
| Test_BW_Time.asc | ok | ok |
| Test_BW_Toshiba.asc | ok | misrepresentation |
| i5-8500 3.60 GHz Win11 V22H2 | LTspice Version 17.0.36.0 | LTspice Version 17.1.6 |
| Test.asc | misrepresentation | misrepresentation |
| Test_BW.asc | misrepresentation | ok |
| Test_BW_Time.asc | ok | ok |
| Test_BW_Toshiba.asc | ok | ok |
Wow, thanks for setting that out so neatly.
I've just fired up an older i5 laptop (from 2012) and using your files above I get the same result in LTXVII (17.0.36.0) as for your i3 processor.
Using the latest version of the new LT (17.1.6) I get the same result as for your i5 processor. Only 'Test' fails to run correctly. Test_BW takes 5 seconds to run on my old i5.
Weird how you have found different processors give different results.
I've just fired up an older i5 laptop (from 2012) and using your files above I get the same result in LTXVII (17.0.36.0) as for your i3 processor.
Using the latest version of the new LT (17.1.6) I get the same result as for your i5 processor. Only 'Test' fails to run correctly. Test_BW takes 5 seconds to run on my old i5.
Weird how you have found different processors give different results.
Here's my results on a AMD A10-7850K
LTspice V17.0.36.0
Test_BW.asc - Takes forever to run, stopped running the test.
Test.asc - runs successfully
LTspice V17.1.6
Test_BW.asc - runs successfully
Test.asc - runs successfully
Interesting the voltage scale using V(vout) on the Test.asc runs are different between the two LTspice versions.
LTspice V17.0.36.0
Voltage at 0ms = -3.32KV
Voltage at 4ms = -357.65KV
LTspice V17.1.6
Voltage at 0ms = -20.53KV
Voltage at 4ms = -385.83KV
The Test_BW_Time.asc and Test_BW_Toshiba.asc both run successfully under both versions of LTspice.
LTspice V17.0.36.0
Test_BW.asc - Takes forever to run, stopped running the test.
Test.asc - runs successfully
LTspice V17.1.6
Test_BW.asc - runs successfully
Test.asc - runs successfully
Interesting the voltage scale using V(vout) on the Test.asc runs are different between the two LTspice versions.
LTspice V17.0.36.0
Voltage at 0ms = -3.32KV
Voltage at 4ms = -357.65KV
LTspice V17.1.6
Voltage at 0ms = -20.53KV
Voltage at 4ms = -385.83KV
The Test_BW_Time.asc and Test_BW_Toshiba.asc both run successfully under both versions of LTspice.
I believe the problems are rooted in LTspice,
less with the processors or the operating system.
Everything can be influenced in these cases with the TimeStep.
Also the lonely resistance, or changing the value and swapping the jfets is strange.
We have to live with it, it can only get better.
less with the processors or the operating system.
Everything can be influenced in these cases with the TimeStep.
Also the lonely resistance, or changing the value and swapping the jfets is strange.
We have to live with it, it can only get better.
Think you are spot on with that last line but thanks for trying all this and adding a bit of insight into it all.
I'm just trying those 4 attached files on my main setup (new i5 11500H Tiger Lake) with LT 17.1.6
Test = Misrepresented
Test_BW = Misrepresented.
Test_BW_Time = runs perfectly. 0.34 seconds to run
Test_BW_Tosh = Misrepresented.
So only one of those four works.
but thanks for trying all this and adding a bit of insight into it all.I'm just trying those 4 attached files on my main setup (new i5 11500H Tiger Lake) with LT 17.1.6
Test = Misrepresented
Test_BW = Misrepresented.
Test_BW_Time = runs perfectly. 0.34 seconds to run
Test_BW_Tosh = Misrepresented.
So only one of those four works.
Using these meas statements with Tian probe causes a crash in the new version. These worked fine with the older version.
.meas ac phase_margin find 1/(1-1/(2*(I(Xlp:Vi)@1*V(Xlp:x)@2-V(Xlp:x)@1*I(Xlp:Vi)@2)+V(Xlp:x)@1+I(Xlp:Vi)@2))
+ when mag(1/(1-1/(2*(I(Xlp:Vi)@1*V(Xlp:x)@2-V(Xlp:x)@1*I(Xlp:Vi)@2)+V(Xlp:x)@1+I(Xlp:Vi)@2)))=1
.meas ac gain_margin find 1-1/(2*(I(Xlp:Vi)@1*V(Xlp:x)@2-V(Xlp:x)@1*I(Xlp:Vi)@2)+V(Xlp:x)@1+I(Xlp:Vi)@2)
+ when ph(1-1/(2*(I(Xlp:Vi)@1*V(Xlp:x)@2-V(Xlp:x)@1*I(Xlp:Vi)@2)+V(Xlp:x)@1+I(Xlp:Vi)@2))=0
.meas ac phase_margin find 1/(1-1/(2*(I(Xlp:Vi)@1*V(Xlp:x)@2-V(Xlp:x)@1*I(Xlp:Vi)@2)+V(Xlp:x)@1+I(Xlp:Vi)@2))
+ when mag(1/(1-1/(2*(I(Xlp:Vi)@1*V(Xlp:x)@2-V(Xlp:x)@1*I(Xlp:Vi)@2)+V(Xlp:x)@1+I(Xlp:Vi)@2)))=1
.meas ac gain_margin find 1-1/(2*(I(Xlp:Vi)@1*V(Xlp:x)@2-V(Xlp:x)@1*I(Xlp:Vi)@2)+V(Xlp:x)@1+I(Xlp:Vi)@2)
+ when ph(1-1/(2*(I(Xlp:Vi)@1*V(Xlp:x)@2-V(Xlp:x)@1*I(Xlp:Vi)@2)+V(Xlp:x)@1+I(Xlp:Vi)@2))=0
I noticed this also when using a working amplifier circuit and the Tian probe wouldn't run. I discovered there is a new way of performing loop analysis. LTspice now uses a new parameter and symbol called .fra. You can find the symbol via >edit>component
There is an op-amp example on your computer in this location-C:\Users\username\AppData\Local\LTspice\examples\Educational\FRA\fra_eg1.asc
I added the .fra parameter to your circuit, it seems to run okay except it couldn't calculate the gain margin because the phase response didn't cross 180degress, it runs fine using the Tian probe in the older version of LTspice.
I'm not a expert at this and can't be sure if I had the .fra parameters configured properly. The .fra parameters can be changed by right clicking on the symbol.
I found it was helpful by having the old version of LTspice to compare the loop gain responses so I could change the .fra parameters to match those of the Tian probe.
There is also additional information in the LTspice Help Topics.
Additional Information
I found using the .fra parameter frustrating, it's really time consuming to get the parameters set correctly so the analysis runs properly and when it does run its really sloooowwww. If you don't have a circuit where you know what the gain and phase margins are from using the Tian probe in the older LTspice versions then you'll have great difficulty in determining whether there is something wrong with the circuit or if the .fra parameters have been configured incorrectly.
As an example the attached ltspice circuit has a weird phase response using the .fra but runs fine using the Tian probe. Am I doing something wrong.......maybe someone else can work it out.
Users should keep LTspice V17.0.36.0 on their computer so they can continue to use the Tian probe for loop gain analysis.
There is an op-amp example on your computer in this location-C:\Users\username\AppData\Local\LTspice\examples\Educational\FRA\fra_eg1.asc
I added the .fra parameter to your circuit, it seems to run okay except it couldn't calculate the gain margin because the phase response didn't cross 180degress, it runs fine using the Tian probe in the older version of LTspice.
I'm not a expert at this and can't be sure if I had the .fra parameters configured properly. The .fra parameters can be changed by right clicking on the symbol.
I found it was helpful by having the old version of LTspice to compare the loop gain responses so I could change the .fra parameters to match those of the Tian probe.
There is also additional information in the LTspice Help Topics.
Additional Information
I found using the .fra parameter frustrating, it's really time consuming to get the parameters set correctly so the analysis runs properly and when it does run its really sloooowwww. If you don't have a circuit where you know what the gain and phase margins are from using the Tian probe in the older LTspice versions then you'll have great difficulty in determining whether there is something wrong with the circuit or if the .fra parameters have been configured incorrectly.
As an example the attached ltspice circuit has a weird phase response using the .fra but runs fine using the Tian probe. Am I doing something wrong.......maybe someone else can work it out.
Users should keep LTspice V17.0.36.0 on their computer so they can continue to use the Tian probe for loop gain analysis.
Hi All.
I even did not now this version was present, did discover after search for a way to do open and closed loop sims, I came here.
After install, and uninstall of the old version I have now set the new simulator up and is working.
I saw direct it was much faster and cleaner, the simulations looks much better.
I just need to learn how to use Fra for openloop gain simulation, but this new ltspice can do much better with class d.
regards
I even did not now this version was present, did discover after search for a way to do open and closed loop sims, I came here.
After install, and uninstall of the old version I have now set the new simulator up and is working.
I saw direct it was much faster and cleaner, the simulations looks much better.
I just need to learn how to use Fra for openloop gain simulation, but this new ltspice can do much better with class d.
regards
Attachments
Hi Here.
I have question about FFT I get such a peaky result, the same when I do normal FFT on standart and do not use blackman-harris
and 5 what I normal do, with the open loop.fra I can not change that and so get peaky result who looks bad.
Can I setup this?
thanks.
I have question about FFT I get such a peaky result, the same when I do normal FFT on standart and do not use blackman-harris
and 5 what I normal do, with the open loop.fra I can not change that and so get peaky result who looks bad.
Can I setup this?
thanks.
Attachments
Mike Engelhard's next thing after LTspice:
< https://www.eenewseurope.com/en/re-writing-spice-for-a-digital-world/ >
< https://www.eenewseurope.com/en/re-writing-spice-for-a-digital-world/ >
Is anybody able to download the file
From this link
https://ltwiki.org/index.php?title=Components_Library_and_Circuits
Im not able to get it to open. If you can. Can you pls re-share it. Or post a link where the download works.
From this link
https://ltwiki.org/index.php?title=Components_Library_and_Circuits
Im not able to get it to open. If you can. Can you pls re-share it. Or post a link where the download works.
A Large LTspice Folder from Bordodynov
It's an outdated model assembly. There is a newer one with many additional models (lib.zip):
http://bordodynov.ltwiki.org/
http://bordodynov.ltwiki.org/
Man thats one insane effort you have put into LT Spice. Can you share a bit about your journey and involvement with the LT Spice project. All my files now open and run. Yes I know there is a steep learning curve. As with anything new.
But I had to post thanking you for your work.
Im a bit confused about LIB existing in two locations I had installed LT Spice on D:
D:\Program Files\LTC\LTspiceXVII\lib
Where I had unzipped all your files. It must have worked cause projects that were not opening earlier are now opening.
But I also see a Lib directory in
C:\Users\Administrator.ThinkPad\Documents\LTspiceXVII\lib
Not sure why there are examples and Lib directories in two locations. Maybe I can knock off one location.