Hi!

I imported the LM358 to LTSpice following this video (I'm fine with this method!) and verified as in the video that the output is clipping about Vcc-1.5V as stated on the datasheet in "Voltage output swing from rail".
So far so good.
(in the meantime I ask you to confirm if the reason for the clipping is what I said... I don't want to be wrong!)

I tried the same thing (same method) by importing from here the OP747, which from the datasheet, if I am not mistaken, has a much lower clipping than 1.5V, about a few mV (correct me here too if I am wrong).

The problem is when I simulate the OP747 .. this error appears:




I think the problem is inside the .CIR file of the OP747 but I really don't know what to do, I am attaching it.

 

The OP747 output can go to within about 10mv of the 5V rail with a 1mA load (below):
It's amazing what you can find in a data sheet.

 

Hi!

I imported the LM358 to LTSpice following this video (I'm fine with this method!) and verified as in the video that the output is clipping about Vcc-1.5V as stated on the datasheet in "Voltage output swing from rail".
So far so good.
(in the meantime I ask you to confirm if the reason for the clipping is what I said... I don't want to be wrong!)

I tried the same thing (same method) by importing from here the OP747, which from the datasheet, if I am not mistaken, has a much lower clipping than 1.5V, about a few mV (correct me here too if I am wrong).

The problem is when I simulate the OP747 .. this error appears:
View attachment 312959

View attachment 312960

I think the problem is inside the .CIR file of the OP747 but I really don't know what to do, I am attaching it.

you are using the wrong symbol.
Use the opamp2 symbol.

 

hi k89,
Try this @Bordodynov version of the LM358.
E

 

you are using the wrong symbol.
Use the opamp2 symbol.

same error:

 

hi k89,
Try this @Bordodynov version of the LM358.
E

Thank you, I will try to use it but I would like to solve the problem I currently have .. do you know how I can proceed?

 

Thank you, I will try to use it but I would like to solve the problem I currently have .. do you know how I can proceed?

Yes you need to dig into the connection between the symbol file and the subcircuit file. There is a mismatch which is causing the error. In my installation the OP747 subcircuit is located in the file ADI.lib

In all probability you already had the symbol and subcircuit for OP747. It is part of the standard installation.

 

Yes you need to dig into the connection between the symbol file and the subcircuit file. There is a mismatch which is causing the error. In my installation the OP747 subcircuit is located in the file ADI.lib

In all probability you already had the symbol and subcircuit for OP747. It is part of the standard installation.
View attachment 313029

I didn't look for the OP747 symbol in the LTSpice library because I simply wanted to learn how to import components from the Internet ... so I downloaded from online catalogs the first two I could think of. I should have checked.

In your experience, do you think this is an error that does not occur with components that I import online and which are NOT already present in the LTSpice libraries?
(that is, an error that only occurs in this cases where the component is already present in the LTSpice libraries)

I'm asking because if the answer is yes, then I'm quite comfortable, but if it's an error that can happen in any situation, then I'm asking for more help in resolving it and 'digging into the connection between the symbol file and the subcircuit file'.

 

Because Spice began life as a text-based simulator without symbols, connecting symbols and subcircuits has always been problematical. It will likely always be this way. To me the error messages given by simulators are in general cryptic and incomprehensible. Importing symbols and subcircuits is not for the faint of heart. You can learn this skill by diligent application of the little grey cells, but you should not expect rapid results.

That said, LTspice and other simulators have a feature where you click on the .subckt line of the file and it will generate a symbol for you. This pretty much guarantees you can avoid certain errors. All you have to do is edit the graphic.