LMH5401-SP: SE to DIFF front end for ADC12D1620QML-SP - Monte Carlo

Hello John,

  I am looking into this, I believe you can use LMH5401 PSpice Model for Monte-Carlo analysis in PSpice for TI or advanced version of Tina-TI.

Thank you,
Sima

Hi Sima,

Thank you for your response.  So the issue is, I am using precision 0.1% resistors and 1% inductors to keep the variation low in the simulation.  I would need to change the global tolerances for R's, L's and C's to the tolerances suggested for the LMH5401 and then change the individual external component tolerances to what I am using.  That is straightforward.  But how do I get the tolerances (over the temperature range) for the LMH5401 model components?

Hi John, I do have a new model for the BUF802 that includes the temperature variation shown in the datasheet. My colleague just completed work on a model sub-circuit where a "MC" directive can be set to "1" on the PSPICE example circuit page that allows a Monte Carlo analysis to be run for offset voltage. We are trying to determine if there is enough interest in these functions to commit time to create models with them for non-new parts.

The only tolerance parameters that we would be able to model are in the ones already in the datasheet, and you should be able to use the tolerances listed there to determine worst case temperature performance. As for Monte Carlo, the typical offset voltage value should be treated as 1 standard deviation, which is truncated at the maximum value spec. 

This is a fully differential amplifier, so I don't think that you will see a phase imbalance with a fully differential input. 

Best regards,

Sean

Well John, the kind of thing you are requesting is of course available internally at the IC designer level using the process models with their variation. Putting that into a public model will probably never happen due to low ROI. However, if you have the budget for a -SP part, perhaps an NDA consulting contract might be the way to go to get some internal designer support for your questions. 

Michael we are evaluating alternatives, I will pass that along, thank you.

Sean, thank you, is the BUF802 model ready for release?

Hello John,

  I believe the model with temperature variation is still in the works for the BUF802. 

  Another engineer on the team has recently worked on worst-case scenarios with a simplified temperature variation and component tolerance using manual insertion of the drift values specified in the device's datasheet. I will also ping him to comment on this thread.

Thank you,
Sima 

Hi John,

can you show a schematic?

Kai

Hello John,

I will be providing comments on how to account for temperature-dependent components in a 'worst-case' scenario.  This will use the extremes of the device's temperature range.

Please allow me a short while to succinctly write this information and get back in touch.

I also would appreciate a schematic to share if you have one available.

Best,

Alec

Hi Sima, the BUF802 TINA-TI model with temperature variation is released. In the future,  will update the existing temperature as a voltage input with an internal "Temperature Controlled Voltage Souce".

Hello Sean,

  Thank you for the update! 

John, 

  Sean's Tina-TI model with the Temp pin and example simulations can be found in the device product folder under the design tools and simulation folder: https://www.ti.com/product/BUF802#design-tools-simulation. 

Thank you,
Sima 

Kai currently I am using the schematic from your eval board with the LMH5401-SP and ADC12DS1620

Sima excellent, thank you all so much!