ADA4896 simulation model

Hello all, 

In the course of consulting on a channel requiring a low noise non-inverting gain - there was also a need to inject a DC offseting level through the inverting Rg path - this needed to be broadband low noise where the ADA4896 seems ideal for this gain of 1 buffer. For non-inverting signal path flatness,the closed loop output impedance of the ADA4896 would be critical. 

The tool I am using has a library model for the ADA4896 ver. 2.1. However, when  I look into the net list (very well organized and easy to read) I see only a fixed 1ohm open loop output resistor

That is extremely unlikely having seen (and modeled) quite a few higher speed RR output stages (see figure 6 in that attached recent article). 

Questions? Is the online PSpice model on the ADI web site updated to a more accurate open loop output impedance? Lacking that, can I least get a more realistic number than this 1ohm place holder. 1ohm is only possible if the output stage is itself closed loop but normally then you would see its own loop gain causing an inductive open loop output impedance (I have modelled plenty of those as well).

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