BUF602: BUF602 TINA model-Noise Density Discrepancy

Well Yash, 

I pulled down the model and indeed the input current noise is about 3.94pA, looked a little inside this transistor based model but could not spot the extra term, 

1. Do not ground the Vref pin, it is a buffer sitting at 2.5V - midsupply, 

Hello Yash,

Unfortunately this isn't a simple fix.. due to the model structure the entire model would need to be reworked in order to more accurately recreate the current noise performance of the part.

Best,

Hasan Babiker

Hi Michael and Hassan,

Thanks for the comment and correction. I will disconnect the ground from the Vref pin.

Can the TINA model be fixed? The Pspice for TI model for this device also does not seem to work. I get identically 0 value from the simulations. Not even resistor noise is being accounted in this case.

Hello Yash,

Not sure what is going on in your Pspice circuit here, could you provide an archived version of the project? Note that Pspice & TINA-TI models are based off the same architecture and you won't get different noise results in Pspice. In regards to fixing the BUF602 model, I've taken note of the issue however the entire model would need to be reworked so there is no current solution for the near future. 

Best,

Hasan Babiker

Hello Hassan,

Sorry for the delayed response. PFA PSPICE files.New folder.zipfiles.

Hello Yash,

You are viewing the trace for output voltage rather than noise. Please add the V(ONOISE) trace to your plot.

Best,

Hasan Babiker

Hello Hassan,

I see no noise trace being generated.

Hello Yash,

Your noise signals aren't selected. You will want to select the "Noise (V^2/Hz)" dialog box to be able to view this trace.

Best,

Hasan Babiker