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Your upload is helpful, but you must post in English. Google Translate is your friend.

Se vuoi dare un'occhiata, ho caricato un file immagine nella sezione foto.
Ok, va bene, ma poi, quando dovrò progettare e costruire il tutto, come collegherò i pin mancanti?
E ??poi, funzionerà correttamente?
Questi sono i miei dubbi.

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That is OK for simulation: commoned pins and NC pins can be left of the symbol and model, but it is a problem when passing data to a PC layout app.

I have not looked at yet - but it is very common for SPICE models to have fewer pins than actual pins.? Also, pin names often vary.

?

Andy

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You may get help here, but you should report your problem the ADI's Engineer Zone, because the different pin numbers is clearly ADI's problem.

Hi, I am designing a Step-up Booster based on LT1680, for some reasons:
1)Suitable for high power;
2)Through hole package;
3)Simple external architecture.
However, there is a discrepancy between the Datasheet and the LTspice component.
It seems there is a mistake with the LTspice file that has only 14 pins while the real component has 16 and some pin names in LTspice are called differently.
Can anyone please help me?
Thanks

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Regarding what I thought was the lack of rail-to-rail output drive:

?

I missed what was happening in your test circuit.? I missed the fact that your negative supply voltage V- was at 0V.? Oops.

No, that was my oops. That was a quick test to see whether that revealed any unexpected behaviour. I hadn't intended to upload that version.

?

And then when I thought I was setting V- to -5V, I actually set it to -(-5)V, which made it appear as if the comparator had failed.? Arrgh, I should give up and go home.? All is OK (except inside my brain).

?

The output impedance is 1 ohm, which should not be a big problem for many users.? But it can affect signals driven into power FETs that have significant input capacitance.? I believe 1 ohm is the default output impedance of LTspice's built-in A-elements.

1 ohm is also the output impedance of the built-in opamp (the one with no supplies that requires '.lib opamp.sub'). The UniversalOpAmps' output impedance is much higher, because the switch elements that form the output have Ron=10, which also severely limits the maximum output current too, regardless what the Ilimit parameter is set to.

--
Regards,
Tony

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Oops, maybe you missed that one.? An easy oversight.

?

• Blistering speed

I am inclined to agree with that.? But I will note that there are some LTspice users who feel its B-elements are much slower than the same circuit without the B-elements.? IIRC, Vlad (one of our group members, who has been quiet here lately) was one of those who had some opposition to B-elements when speed was critical.? I don't want to imply that there is anything wrong with them, but it's possible that a built-in "Digital" gate might be faster - although somewhat more cumbersome to use.

My (very) limited measurements suggest that the B-source is about 5-10% slower than an A-source, but that might vary considerably with processor and circuit complexity (I only tried on my Ryzen 9 machine, which is over twice as fast as my last one according to my previous tests). I also found that LTspice XVII was consistently around 20% slower than 24.0.12. This is all less significant than suggested by "much slower".

Your (other) comment about an open-collector (or open-drain) output had me thinking half the night. So far, I haven't come up with a simple way to make that an option using the present form of the transfer function without adding extra bits. It's a useful suggestion though, and the option should be available, as O/C comparators are fairly common and are practically useful, whereas the LM311-type O/C-O/E variant is almost unique anyway, so there's not much point in emulating it.

Whether or not to hard-code the ModelFile attribute is a thorny one. My personal feeling is that I don't like doing that with symbols and models that are not core LTspice ones, for the simple reason that all users will have the built-in ones, but for added symbols users should be explicitly prompted due to the issues we're familiar with in sharing schematics. Anyone that feels strongly about it can make their own versions.

--
Regards,
Tony

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Very helpful. It would be good to add a .ZIP of all the files to the folder.

All LTspice users should be familiar with UniversalOpamps. There are 7 different UniversalOpAmp models of increasing complexity capable of modelling almost any proprietary opamp to reasonable levels of accuracy in most regards, typically with superior convergence and speed within LTspice.

I see quite a few people using opamps to model comparators, despite the requirements being quite different. It occurred to me this might be because there isn't an equivalent universal comparator. So I set out to change that.

The UniversalComp is the simplest solution I could think of with just one B-source, and it features:

• Programmable Propagation Delay (trapped to prevent values <0)
• Programmable Hysteresis (trapped to prevent values <0)
• Rail-to-Rail Output
• Excellent convergence
• Blistering speed
• Infinite Common-mode Input Range

I have also made two symbols, with the inputs reversed for drafting convenience, that are otherwise pin-wise compatible with the opamp2 and UniversalOpAmp symbols. The model and a test schematic is also available in Universal Comparator.

--
Regards,
Tony

开云体育

All LTspice users should be familiar with UniversalOpamps. There are 7 different UniversalOpAmp models of increasing complexity capable of modelling almost any proprietary opamp to reasonable levels of accuracy in most regards, typically with superior convergence and speed within LTspice.

I see quite a few people using opamps to model comparators, despite the requirements being quite different. It occurred to me this might be because there isn't an equivalent universal comparator. So I set out to change that.

The UniversalComp is the simplest solution I could think of with just one B-source, and it features:

• Programmable Propagation Delay (trapped to prevent values <0)
• Programmable Hysteresis (trapped to prevent values <0)
• Rail-to-Rail Output
• Excellent convergence
• Blistering speed
• Infinite Common-mode Input Range