OPA653: .CIR model

In the model file it states that the model will not provide accurate input current noise. Is there an updated version 

of the model or a device similar in scope to the OPA653 that does model input noise V and I properly. The main 

focus in this work is noise and noise figure. I need a device that has proper noise model and en and in values near

those of this amplifier, 5-6 nV per root Hz and less than 2 fA per root Hz. GBW of GT 500 MHz is also needed Thanks, 

Hello Dr. Alan,

I recognize your target values near the written amplifier spec of 6.1nV/sqrt(Hz) input voltage noise and 1.8fA/sqrt(Hz).

Are you looking to confirm the amplifier spec via simulation, or to evaluate a system-level solution with the OPA653 as part of the system?

Another option may be to look into bench data for this device, if you have a critical need for simulating or measuring noise on this part.

Let Nick and I know what your system level needs are here; I do not think we can tweak or update the model expeditiously, or if we even have the capability to do so.

If we are able to help, we would like to do what we can to support your design.

Best,
Alec

Thank you again for quick response. Yes, I am looking at a unique source to input to the OPA. The source has a 

known and specific characteristic impedance versus frequency and in the ideal case, I wish to target a unity gain buffer

that has an optimum source Z that matches this source. The end result, to maximize SNR. Or minimize the NF of the system. 

So I am embedding the unique source at the OPA input and evaluating system NF. 

I ran a noise simulation for the OPA653 and selected a source Z that would provide the optimum value for NF minimum at 10 MHz.  

This source R value is based on the stated parameters from the data sheet for input noise voltage and noise currents. The simulation 

results are incorrect as might be expected from reading the model notes and disclaimers. So, this at least confirms that other paths must be 

selected. Thank you.  

What about the OPA657 and  is a .CIR list available?  Is noise handled correctly in this model release? Thank you. 

Excellent again Nick. Many thanks!