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Re: AKO: Fails When Placed in Sub-Schematic
¿ªÔÆÌåÓýOn 09/02/2025 15:05, Dennisc via
groups.io wrote:
In the case of LTspice, undocumented features were not guaranteed to remain available. Many programs contain them - one of the best examples being Microsoft Excel. AKO is a Donald Rumsfeld example of a "known unknown". There are also some "unknown unknowns", or at least, there used to be. Features that were used internally at LTC, but not intended to be used or even known externally. Analogspiceman found a number of those, and along with Helmut Sennewald, erased all traces, at least within this group and in the LTwiki, at the request of LTC. There is now possibly no one left to ask about those. But I may be wrong. -- Regards, Tony |
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Re: AKO: Fails When Placed in Sub-Schematic
¿ªÔÆÌåÓýIndeed; the need for it in the subcircuit case
seems to be a b-u-g. On 2025-02-09 02:19, eewiz via
groups.io wrote:
-- OOO - Own Opinions Only Best Wishes John Woodgate Keep trying |
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Re: AKO: Fails When Placed in Sub-Schematic
¿ªÔÆÌåÓýA case for carefully examining the netlists, I
suppose. On 2025-02-09 01:57, Andy I via
groups.io wrote:
-- OOO - Own Opinions Only Best Wishes John Woodgate Keep trying |
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Re: How to Set Up Permanent UniversalOpamp Doppelganger
¿ªÔÆÌåÓýOn 09/02/2025 04:25, eewiz via
groups.io wrote:
If you want to decouple your NE5532L3A from ADI's distributed copy of UniversalOpamp3A, simply make a copy of the current UniversalOpamp3A.lib with the parameter customisations, and rename it NE5532L3A.lib. Put that with your collection of personal models, which I assume is listed in Control Panel > Search Paths > Library Search Paths [*] To use it as any other 3rd party opamp: 1. Place an opamp2 symbol in your schematicDone. You won't have interactive access to the parameters, like you would with a generic UniversalOpamp. but know it won't ever change. If you want to grab an NE5532L3A direct from the component chooser, a couple more steps: 4. Make a copy of opamp2.asy, call it NE5532L3A.asyDone. If you prefer to go with any future version of ADI's UniversalOpamp3A, improved or not, just modify your NE5532L3A .subckt: NE5532 Source: UniversalOpAmp Level3A .SUBCKT NE5532L3A?? 1 2 3 4 5 X 1 2 3 4 5 level3a Avol=50k GBW=7.2Meg Slew=9Meg ilimit=38m rail=1.5 Vos=0 phimargin=60 en=5n enk=40 in=0.7p ink=150 Rin=50k * .lib UniversalOpamp3A.lib .ENDS Execute steps 1-3, above. -- Regards, Tony |
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How to Set Up Permanent UniversalOpamp Doppelganger
Hello All:
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I'm trying to use the UniversalOpamp level3a to emulate the NE5532 opamp.
This is so I can place a part named NE5532L3A on my schematic which will actually use the level3a universal opamp with all of it's params set correctly to emulate the NE5532.
TI's NE5532 model won't converge and further causes subsequent sudo-random DEFCON lockups.
I already have my project working by "P" placing the UniversalOpAmp3a.asy on my schematic and then setting all params as necessary.
I took the "X 1 2 3 4 5 level3a" stuff from my netlist and am now attempting to add it to my NE5532.lib file.
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I keep my opamp/comparator type .lib files with many related devices in each, so I can select one from the many lets say LM339/393 models I have collected along the way.
My NE5532.lib file currently holds two copies of the TI model.
One standard and one modified to draw its output current through its power pins which TI's standard NE5532 model does not.
Both models won't converge among other issues already mentioned.
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I tried this:
NE5532 Source: UniversalOpAmp Level3A
.SUBCKT NE5532L3A?? 1 2 3 4 5 X 1 2 3 4 5 level3a Avol=50k GBW=7.2Meg Slew=9Meg ilimit=38m rail=1.5 Vos=0 phimargin=60 en=5n enk=40 in=0.7p ink=150 Rin=50k * .ENDS ?
24.0.12 says "Undefined subcircuit: level3a".
I located the UniversalOpAmp3a.lib file and copied its contents, ".SUBCKT level3a" to ".ENDS", into the above where the star in now located. That works; it has no problem finding level3a when the level3a subcircuit is available locally.
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I hoped that since a "P" placed UniversalOpAmp3a.asy can find the level3a sub-cicuit that the above would work.
But, alas, it does not.
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LTspice's UniversalOpAmp3a.lib file is located at "C:\Win32\LTC\LTspice\lib\sub".
I tried "X 1 2 3 4 5 C:\Win32\LTC\LTspice\lib\sub\UniversalOpAmp3a.lib\level3a Avol=50k etc..." and it said it can't find that either.
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I would like to avoid using a copy of ADI's level3a sub-circuit because ADI may improve it in the future leaving my copy without those improvements.
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Please help me with the correct syntax to use ADI's level3a sub-circuit from where it normally resides.
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Thank You |
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Re: AKO: Fails When Placed in Sub-Schematic
LTtwiki also shows the AKO: syntax without the "NPN" parameter.
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Sent:?Saturday, February 08, 2025 at 8:37 PM
From:?"Andy I via groups.io" <AI.egrps+io@...> To:[email protected] Subject:?Re: [LTspice] AKO: Fails When Placed in Sub-Schematic Model definitions SHOULD work at any level including inside subcircuits.? In fact it is kind of a necessity.? One may want to use a model name and not have it conflict with another of the same name, and the best way to do that is to move the model definition inside the subcircuit, thus making it local to that subcircuit only.? I think it has always been that way in SPICE.
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It is most curious that adding "NPN" to the statement seems to fix it, and that "NPN" is not needed outside of subcircuits.? I'd say it is a bit buggy.
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AKO never was documented in LTspice's Help.? You can find it in the "Undocumented LTspice" section of the LTwiki, .? The parentheses thing does not surprise me, as that is pretty much the norm for SPICE (with a few exceptions).
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Andy
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Re: AKO: Fails When Placed in Sub-Schematic
Hello All:
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It works in a sub-circuit when the "NPN" is included in the statement.
In all places where it does work, it works with or without the parentheses.
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Searching the help file for "AKO" or "ako" has zero hits.
Many Internet sources show: ".model My5551 ako:MMBT5551 Bf=80" (without the "NPN" parameter).
They are not patently wrong since it does work correctly on a top level schematic without the "NPN" parameter.
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All for now
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Sent:?Saturday, February 08, 2025 at 4:38 PM
From:?"eetech00 via groups.io" <eetech00@...> To:[email protected] Subject:?Re: [LTspice] AKO: Fails When Placed in Sub-Schematic Use:
.model LoBT5551 ako:MMBT5551 NPN (Bf=80)
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Re: AKO: Fails When Placed in Sub-Schematic
¿ªÔÆÌåÓýI think it's reasonable that subcircuits have
limited intelligence and require key data to be specified at the
top level. I suppose this is not documented in the Help, but to
document everything in LTspice (perhaps even in SPICE would
require more than the proverbial three-volume novel. I have one
app that has a PDF manual that is nearly 1 GB, Admittedly, it
has many graphics, but even trying to search it is daunting. So
I don't use it unless I absolutely have to. On 2025-02-08 21:30, eewiz via
groups.io wrote:
-- OOO - Own Opinions Only Best Wishes John Woodgate Keep trying |
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AKO: Fails When Placed in Sub-Schematic
Hello All:
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I have discovered that the spice statement ".model LoBT5551 ako:MMBT5551 Bf=80" fails if placed on a sub-schematic where the "LoBT5551" transistor is located.
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LTspice 24.0.12 says "Can't find definition of model LoBT5551".
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Moving the AKO: statement to the top-level schematic works as expected.
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All for now
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Re: Any Good Reason to Create a Hierarchical Connector and Conductors to Route (Plumb) Ground Out of a Hierarchical Schematic
Hello eetech00:
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Break a huge schematic that has grown so large it can't be easily read from one monitor into a dozen sub-schematics.
Those sub-schematics now have grounds peppered all around.
This lead me to the question which is the title of this thread.
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I did not intend to add grounds.
I wanted to understand the ramifications of leaving those to-be-hidden grounds behind, or routing ground out of the hierarchical schematic to be connected on a top level schematic.
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After these discussions, I understand the need to remove all triangular (label 0) ground symbols from the interior of a hierarchical block and physically connect any nets that may have been disconnected by those ground symbol removals.
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I discovered first hand those confusing probe readings within a sub-circuit as detailed in my have a look here submission.
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All for now
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Sent:?Saturday, February 08, 2025 at 10:14 AM
From:?"eetech00 via groups.io" <eetech00@...> To:[email protected] Subject:?Re: [LTspice] Any Good Reason to Create a Hierarchical Connector and Conductors to Route (Plumb) Ground Out of a Hierarchical Schematic On Fri, Feb 7, 2025 at 11:28 PM, eewiz wrote:
HI eewiz ?
I see what you've explained.
But in my humble opinion, it appears to be caused by a misuse of labels. When you add a ground symbol, you are basically adding a reserved label named "0" (zero). It has been known for years that a net should not have multiple dis-similar labels.
What is the intent of internally grounding the RTN pin?
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Tony Casey
John Woodgate
eewiz
jacfev