Re: Calculate average value of a waveform under specific conditions using .meas command
Ankit,
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Comparing a waveform with a precise value can sometimes be tricky, especially when there is ringing or other noise.? I do not know if this helps, but you might need to add guard bands around the signal used to trigger the .MEAS commands.? For example:
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... TRIG I(L_filter_dc)<50m ...
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or something like that, rather than testing for I(...)=0.? It might affect the accuracy of the measurement, so choose the values carefully.? Basically you are trying to tell a computer to do something that you can "see" by looking at it, except that the waveforms are not perfect.
?
Andy
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Re: Calculate average value of a waveform under specific conditions using .meas command
As I understand it, it is permitted to upload
a diagram or a SHORT piece of text from a copyright paper, but
nothing more.
On 2025-05-06 13:29, Andy I via
groups.io wrote:
... Although, I do have a downloaded version of the paper
which I am not sure if I can upload here (can I upload
material that is not open source and can be subject to
copyright?). If it is okay then I will upload it
immediately.
I do not think you should upload THAT paper.? If it was also
freely available for download from another website, then maybe
you could.? But the copy you downloaded from the IEEE website is
for your use only.
?
Is there important information from the paper that we need to
see, to understand the problem you are trying to solve with your
.MEAS commands?
?
Andy
?
--
Best wishes John Woodgate RAYLEIGH Essex OOO-Own Opinions Only
If something is true: * as far as we know - it's science *for
certain - it's mathematics *unquestionably - it's religion
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Re: Calculate average value of a waveform under specific conditions using .meas command
On Tue, May 6, 2025 at 05:59 PM, Andy I wrote:
Is there important information from the paper that we need to see, to understand the problem you are trying to solve with your .MEAS commands?
Not really, it is just that other waveforms have to be averaged during the corresponding time intervals. For example during switch ON state the capacitor voltage follows one particular equation so it is necessary to calculate the average of the capacitor voltage during ON state. During OFF state the equation is different so I need to calculate a second average. Similarly the third average for DCM mode.
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Re: Calculate average value of a waveform under specific conditions using .meas command
On Tue, May 6, 2025 at 08:18 AM, <ankitk.ace@...> wrote:
... Although, I do have a downloaded version of the paper which I am not sure if I can upload here (can I upload material that is not open source and can be subject to copyright?). If it is okay then I will upload it immediately.
I do not think you should upload THAT paper.? If it was also freely available for download from another website, then maybe you could.? But the copy you downloaded from the IEEE website is for your use only.
?
Is there important information from the paper that we need to see, to understand the problem you are trying to solve with your .MEAS commands?
?
Andy
?
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Re: Calculate average value of a waveform under specific conditions using .meas command
On Tue, May 6, 2025 at 05:52 PM, Andy I wrote:
Did you have a .MEAS command that worked, and other commands that failed?
Hello Andy,
?
I am sorry. My message was cluttered and that's probably the .MEAS command was overlooked.
?
The command that I have provided worked. However, I am not sure if the command is correct to calculate the average during the first DCM period. Could you compare this command with the screenshot that I have shared here and tell me if it is correct or not? If yes, then can you help me with my other remaining queries:
a) How to detect the nth interval of switch being ON and inductor current is building up during this duration?
b) How to detect the kth interval of switch being OFF and inductor current ramps down during this phase?
c) How to detect the mth DCM interval?
With Regards,
Ankit
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Re: CD4000 Library Additions
Need to remove the link in message? ? #160216 as it was part of the reply.
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Re: Calculate average value of a waveform under specific conditions using .meas command
On Tue, May 6, 2025 at 08:14 AM, <ankitk.ace@...> wrote:
I had mentioned the command in my initial message for the first DCM operation. I used:
.meas TRAN Vavg AVG V(Unfolding_topside,Right_negative) TRIG I(L_filter_dc)=0 TD=33ms FALL=1 TARG I(L_filter_dc)=0 TD=33.1ms RISE=1
I'm sorry.? I thought you said that was the .MEAS command that worked.? You wrote " I was able to determine the average using the following command".? I guess I misunderstood what you meant.
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Did you have a .MEAS command that worked, and other commands that failed?
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Andy
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TI Battery Charger(BQ24610) and EFuse(TPS26636) ICs
Hey there everyone,
I have been trying to get my hands on the spice models for a couple of ICs from TI to no avail. They are the BQ24610 battery charging and power management IC and the TPS26636 E-fuse IC.?
I want to design a battery charger for 4S lithium 18650 batteries, as well as a resettable over current protection module. These are 2 separate projects.?
Any advice on how to obtain these models, or at least have some way of modelling them on LTSPICE?
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Re: Calculate average value of a waveform under specific conditions using .meas command
On Tue, May 6, 2025 at 05:33 PM, Tony Casey wrote:
Please don't include links to non-free websites. IEEE papers are not normally available to people without individual or employer/university membership, unless you pay for it.
Hello Andy,
?
I am sorry. Next time onwards I will not include links that are hidden behind a paywall. Although, I do have a downloaded version of the paper which I am not sure if I can upload here (can I upload material that is not open source and can be subject to copyright?). If it is okay then I will upload it immediately.
With Regards,
Ankit
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Re: Calculate average value of a waveform under specific conditions using .meas command
On Tue, May 6, 2025 at 05:17 PM, Andy I wrote:
What is/are the .MEAS command(s) you used?
Thank you for such a prompt response, Andy. The error that I got during many iterations was "MEASUREMNT FAIL'ed" while trying to set appropriate TRIG and TARG conditions. I had mentioned the command in my initial message for the first DCM operation. I used: .meas TRAN Vavg AVG V(Unfolding_topside,Right_negative) TRIG I(L_filter_dc)=0 TD=33ms FALL=1 TARG I(L_filter_dc)=0 TD=33.1ms RISE=1
?
However, I am not sure if what I did with this command is correct or not. Also, there's a a resonance between the inductor and the capacitor during DCM, therefore, the inductor current is crossing zero numerous times within the same period.
?
It is cumbersome to manually use cursor to detect each value of time interval where I need to calculate the averages. Is there a way to automatically determine these time intervals? For instance:
a) How to detect the nth interval of switch being ON and inductor current is building up during this duration?
b) How to detect the kth interval of switch being OFF and inductor current ramps down during this phase?
c) How to detect the mth DCM interval?
I can genuinely use your expertise on this. It is a request
With regards,
Ankit
PS: I cannot share my schematic because it is a unique topology and I have yet to publish my paper.
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Re: Calculate average value of a waveform under specific conditions using .meas command
On 06/05/2025 13:38, ankitk.ace via
groups.io wrote:
For my thesis I am trying to analytically derive the small
signal transfer function of a practical buck converter topology
with all the parasitics included. I am using this paper as .
The dc side inductor is operating in DCM. I have to calculate
the average value of the filter capacitor under 3 different
conditions as shown in the
attached screenshot. ?
For the first DCM operation I was able to determine the
average using the following command
.meas TRAN Vavg AVG V(Unfolding_topside,Right_negative) TRIG
I(L_filter_dc)=0 TD=33ms FALL=1 TARG I(L_filter_dc)=0 TD=33.1ms
RISE=1
However, for the first duration of switch ON after 33 ms and the
first duration of switch OFF after 33 ms I am unable to
implement the syntax. I am continuously getting an error in it.
I am not even sure if the syntax that I have used to calculate
the average during DCM is correct too. Likewise, if I have to
calculate the average of the capacitor voltage during second DCM
period after 33 ms how should I change my syntax?
I would be grateful if anyone can help me with these issues.
Please don't include links to non-free websites. IEEE papers are not
normally available to people without individual or
employer/university membership, unless you pay for it.
--
Regards,
Tony
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Re: Calculate average value of a waveform under specific conditions using .meas command
On Tue, May 6, 2025 at 07:38 AM, <ankitk.ace@...> wrote:
.... I am using this paper as . ...
FYI, that paper requires membership in IEEE to access it.? It would not be a good idea to refer to a research paper that many members can not see without paying for it.? If there is publicly accessible information to the same data, it would be good to use that instead.
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Andy
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Re: Calculate average value of a waveform under specific conditions using .meas command
On Tue, May 6, 2025 at 07:38 AM, <ankitk.ace@...> wrote:
However, for the first duration of switch ON after 33 ms and the first duration of switch OFF after 33 ms I am unable to implement the syntax. I am continuously getting an error in it. I am not even sure if the syntax that I have used to calculate the average during DCM is correct too.
What is/are the .MEAS command(s) you used?
?
What is the error message you saw?
?
Please don't leave us in suspense.? It does not help to tell us that you get some unspecified error, from a .MEAS command that you didn't show.
?
Likewise, if I have to calculate the average of the capacitor voltage during second DCM period after 33 ms how should I change my syntax?
Remember that if you know the exact times where you want to average a waveform, you can specify those exact times.? You can get those times from the "attached cursors" in the waveform window.
?
Andy
?
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Calculate average value of a waveform under specific conditions using .meas command
Hello everyone,
?
For my thesis I am trying to analytically derive the small signal transfer function of a practical buck converter topology with all the parasitics included. I am using this paper as . The dc side inductor is operating in DCM. I have to calculate the average value of the filter capacitor under 3 different conditions as shown in the attached screenshot. ?
For the first DCM operation I was able to determine the average using the following command
.meas TRAN Vavg AVG V(Unfolding_topside,Right_negative) TRIG I(L_filter_dc)=0 TD=33ms FALL=1 TARG I(L_filter_dc)=0 TD=33.1ms RISE=1
However, for the first duration of switch ON after 33 ms and the first duration of switch OFF after 33 ms I am unable to implement the syntax. I am continuously getting an error in it. I am not even sure if the syntax that I have used to calculate the average during DCM is correct too. Likewise, if I have to calculate the average of the capacitor voltage during second DCM period after 33 ms how should I change my syntax?
I would be grateful if anyone can help me with these issues.
With regards,
Ankit
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Re: CD4000 Library Additions
On Tue, May 6, 2025 at 06:04 AM, Tony Casey wrote:
BTW, please don't include links to imgur or other dodgy external storage sites.
Agreed!? That link to imgur.com was a Very Bad Idea.? Did you read the guidelines for this group?? Links to bad and dodgy third-party websites should not be used in this group.
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Andy
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Re: CD4000 Library Additions
BTW, please don't include links to imgur or other dodgy external
storage sites. If you have images etc. you want to share, please
upload them to Photos.
For datasheets, you could include a link to the manufacturer's page,
but they are likely to change over time, so the link may not work a
few years later. Whereas anything uploaded to this group's pages
stays there (unless the uploader deletes them).
--
Regards,
Tony
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Re: CD4000 Library Additions
On 06/05/2025 11:13, N4 via groups.io wrote:
I have looked through the most recent files, but wasn't as lucky as you to find CD4026/CD4033 included in the linked libraries.?
[Mod note: Link deleted.]
?
Which brings me back to the original post here and @eetech00, who has offered to share these symbols as they were, and seem to still not be part of the libs available for download.?
?
If you have them and I am just blind, plz link them to me, it has been hours.?
Sorry, I missed that you were still looking for the CD4026. Unfortunately, the libraries don't include those parts. Somebody enquired about the CD4026 once before back in 2013 in the message thread beginning #68632. Nobody has ever made the model, AFAIK. The suggestion then was to make it from the constituent gates that exist in the library according to the logic diagram in the CD4026 datasheet. I doubt there ever will be a more complete model, since the demand for this was so low. -- Regards, Tony
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Re: CD4000 Library Additions
Thanks for the response Tony.?
?
I have looked through the most recent files, but wasn't as lucky as you to find CD4026/CD4033 included in the linked libraries.?
[link to imgur.com removed by Moderator]
?
?
Which brings me back to the original post here and @eetech00, who has offered to share these symbols as they were, and seem to still not be part of the libs available for download.?
?
If you have them and I am just blind, plz link them to me, it has been hours.?
?
?
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Re: Passing a Mosfet Value as a parameter to a hierarchical subcircuit
You are right. 24.1.8 has not installed
itself.
On 2025-05-06 07:17, Mathias Born via
groups.io wrote:
That's not the 24.1.8 help, then. You must have looked at an
older version.
?
On Tue, May 6, 2025 at 12:22 AM, John Woodgate wrote:
Well, it's hardly hidden
away. It's the third short paragraph in the .PARAM help:
To invoke parameter substitution
and expression evaluation, enclose the expression in
curly braces. The enclosed expression will be replaced
with the floating-point value.
--
Best wishes John Woodgate RAYLEIGH Essex OOO-Own Opinions Only
If something is true: * as far as we know - it's science *for
certain - it's mathematics *unquestionably - it's religion
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Re: CD4000 Library Additions
On 06/05/2025 09:02, N4 via groups.io
wrote:
I have randomly
found this topic while searching for CD4026 library for LTS. Would
you still be able to share your extended library??
I guess you didn't search the Files section of the
group's website. If you had searched for "CD4000 library" (in the
top-right corner), you would have seen 18 hits.
The most recent model libraries:
CD4000.lib
- for the "standard" model library
CD4000_v.lib
- for a slightly modified version where the actual logic levels
tracks the actual voltage on the VDD net, which must be present.
..and:
CD4000.zip
- symbols for the above models. Use these, instead of making your
own, as they properly define the required parameters.
--
Regards,
Tony
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John Woodgate
DerekK
Tony Casey