PSpice model for TLE2141

Hello y.i.,

The basic TLE2141 op amp model was developed in 1990, which makes it quite dated. Simulation models developed in that era were not very sophisticated, but advances in circuit modeling and models were being made at the time. The result was a particular op amp might have several simulation model versions optimized for a certain operating condition, or to take advantage of a different internal architecture that modeled some parameters more closely. That is the case for the different TLE2141 models.

When you opened the tle2141readme.txt file it provided a brief explanation about each of the four different TLE2141 models. The first two are optimized for +5 V supply operation. The last two are optimized for +/-15 V operation. Then, each supply grouping has a Level 1, or Level 2, model. I that has to do with the model type. I don't know for certain, but I think the Level 1 uses the Scichman-Hodges model, and level 2 uses a geometry-based, analytic model. Even if that is correct I am not enough of a model guru to tell you what that means, or implies. What I do know from experience is that I usually don't see much difference in the simulation results when I use one, or the other level of model.

Use a model that comes closest to your application's supply voltage; either one of the +5 V models, or one of the +/-15 V models. When I encounter the Level 1, or Level 2 issue, I tend to use the latter. I don't think you will see much difference in the simulation results between the two.

Regards, Thomas

PA - Linear Applications Engineering

Hello y.i.,

On-line information indicates that the common use of Level 1 and Level 2 in models refers to the type of MOSFETs a simulation model uses; the Shichman-Hodges, or analytic model. But when I review the Spice syntax inside text listings for the TLE2141 Level 1 and Level 2 models I am not finding any MOSFETs.  Therefore, I now think the Level 1 and Level 2 designations have a different meaning in this case.  

I recognize that the Level 1 model is the common Boyle Model, a behavioral model used for operational amplifiers. It was in common usage during the time when the TLE2141 was developed. Here's some information about it:

http://e2e.ti.com/blogs_/b/analogwire/archive/2013/12/23/what-s-the-difference-between-macro-models-and-behavioral-models

http://www.ti.com/lit/an/sboa027/sboa027.pdf

The Level 2 model does look to be the Boyle model too, but with more of the amplifier's behaviors modeled. There are additonal lines of code indicating voltage-controlled current sources, and current-controlled current sources, that the Level 1 model doesn't include. I think their purpose might be to better model the CMR and PSRR behaviors of the TLE2141, but I am not certain. 

I am not an expert on the Boyle Model details. If you need more understanding about the model differences between these two models, the modeling Engineers monitoring TI's Webench Tools E2E forum might be able provide that information. They have in-depth understandings of model architectures.

Regards, Thomas

PA - Linear Applications Engineering