I keep receiving this error in OrCAD. I am trying to use an LM741 operational amplifier for my schematic but am unsure why I can't open it.


Placing symbol instance for Model LM741 failed because in Demo mode Library path opamp does not exist

Here is the circuit:

I need to use the LM741 op-amp but maybe there is another op-amp that will produce the same results?

  • 3
    \$\begingroup\$ Is this a sign that OrCAD has moved into the 21st century and no longer supports the ancient 741? Maybe just wishful thinking on my part ... \$\endgroup\$ – brhans Nov 2 '20 at 4:04
  • \$\begingroup\$ @brhans - funny that you said that I was just reading about how old the part is. My professor is making us use a LM741 and I just don't understand why. \$\endgroup\$ – Geno C Nov 2 '20 at 4:05
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    \$\begingroup\$ @GenoC My professor is making us use a LM741 and I just don't understand why. That's because textbooks (the 50-year-old ones and even the newer ones) have been using the model-741 for opamps. That was so even when I was in university (early 2000s). \$\endgroup\$ – Rohat Kılıç Nov 2 '20 at 5:56
  • 1
    \$\begingroup\$ Just simulate using another op-amp and rename it 741. \$\endgroup\$ – Andy aka Nov 2 '20 at 9:52
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    \$\begingroup\$ It's great to learn with a 741 because you'll face all the classic opamp issues right away and learn what they are and how to avoid them, instead of being surprised later on. But it sounds like your problem here isn't the opamp, but you may not have the required license to use your Orcad. \$\endgroup\$ – user_1818839 Nov 2 '20 at 14:28

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