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I have just started using LTSpice. I need to simulate a circuit with op amps, where the parasitic elements of the op amp may effect performance. So I need to try different 'real' op amps to see which on is best.

Is there a source of commonly available op amp models like TL074 or LM324

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  • \$\begingroup\$ Many models are found with the manufacturer's websites along with datasheets - usually on the same page. I recently prepared an on-line tutorial on how to find manufacturer models and then how to integrate them into LTspice. The link: How to Use a Chip Vendor Op-Amp Model In LTSpice \$\endgroup\$ – Ron Fredericks Jun 11 '18 at 2:13
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From the manufacturers. For example TL074 spice model

Be aware there are sometimes problems with manufacture's spice files. I have found that they sometimes use node zero in parts of the internal circuit. This result of this is that the model works fine unless you supply it from power rails at a potential far removed from your circuit ground. Also you sometimes need to do a little bit of translating of p-spice specific syntax.

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The LTSpice Yahoo group is the place to go. You can download models of many common devices.

Also keep in mind that while models of real op-amps are pretty good, they are far from perfect, and may not simulate all the parasitics in a real circuit. If you are very concerned about parasitics, there's little you can do other than building the circuit and measuring.

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  • \$\begingroup\$ this one might avoid the translation problems mentioned in my answer \$\endgroup\$ – user1582568 Jan 25 '16 at 19:30
  • \$\begingroup\$ Thank you, I would always build a real circuit as well. I am working at audio frequencies so maybe the simulation will be quite good because the parasitics are simpler at low frequency. \$\endgroup\$ – John Spence Jan 25 '16 at 20:11
  • \$\begingroup\$ Yup, at audio frequencies, any decent op-amp should behave well and parasitics won't be much of a factor. The significant differences will be maximum voltage swing and input/output impedance. \$\endgroup\$ – uint128_t Jan 25 '16 at 20:13
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Check out: http://ltwiki.org/

This site has many of the models, components.

And read here: http://ltwiki.org/LTspiceHelp/LTspiceHelp/Third_party_Model.htm

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