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OPA313: Interaction between OPA313 and OPA316 pspice models

Intellectual 860 points

Replies: 8

Views: 51

Part Number: OPA313

Current issue is that I am comparing some circuits using OPA313, OPA314, and OPA316 pspice models.  If I simulate identical circuits using OPA313 and OPA314 in the same schematic, I get results as I would expect.  As soon as I add an OPA316 to a copy of the circuit, the OPA314 response but the response of the circuit with the OPA313 drops to a much lover output voltage and longer time constant.  This interaction only seems to affect the transient analysis as the AC analysis is fine.  I didn't check noise.  I have checked to make sure there are no nodes in the schematic with common names so I'm not accidentally linking the copies of the circuits. 

I have seen behavior like this with various models over many years and in different simulators (Pspice, Multisim, and LTSpice) and always assumed there was something in the macromodel that was referencing a common node, likely ground.  I started to compare the OPA313 and OPA316 models and they share a lot of common names and also reference node 0, but this isn't uncommon in other models.  The OPA314 model shares many of the internal names and doesn't exhibit this problem.

The other odd thing is that it is only the OPA313 response that is changed.  The OPA316 response is the same regardless of if there is an OPA313 in the simulation or not.

But I decided to ask to see if anyone else has had the problem and knows of a simple solution.  I like having the models in the same schematic so I can contrast the response differences (it's a teaching application).

I appreciate any suggestions or insight.  I really need to get out of the house on a Saturday :)

Tim