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THS2630: Are spice models available for this part (THS2630)

Part Number: THS2630
Other Parts Discussed in Thread: THS4131, , TINA-TI

I have a design that use the THS4131ID and this part is going obsolete and I am looking to replace it with new part THS2630 that is recommended on the THS4131 web page.

I have purchased sample parts and replace the THS4131 with the THS2630 and the noise floor is 3 x higher than the originals part. This part is used to drive a muti pole LC anti aliasing filter and then a second amplifier drives the input to the a LTC2206 ADC. Switch back to the THS4131 and the noise floor is back to the original noise level.

This does not seem correct results and the THS2630 has slightly better noise specks and very similar other specifications.

I have done my simulation of the THS4131 in LTspice and would like to use the same tool to evaluate, via simulations, the THS2630 but I only find a TINA model on TI website. Do you have an unencrypted spice model for the THS2630 available and any Idea why the new part might be showing the higher noise.

  • Hi Craig,

    Attached is the .lib file for the THS2630

    THS2630.lib

    I have also completed a simulation of the circuit you provided in TINA-TI and the noise performance is improved in the THS2630 vs the THS4131 for that simulation. 

    THS4131 simulation:

    THS2630 simulation:

    It is peculiar that you are seeing a noise floor on the THS2630 that is much higher than that of the THS4131. Can you provide the measurements that you are seeing?

    Thanks,

    Nick

  • Thank you very much for the SPICE model and your analysis. We are going to redo our noise test and I will let you know what we find. There is a programable gain stage before the circuit I published and we can not verify that this was set the same for both test and the noise of the circuit is dominate by the source not the circuit simulated here. So I want to redo the test with proof of the gain settings.

  • Hi Craig, 

    Thank you for providing that update. Please let me know after you complete your rerun of the noise test if the issue still persists.

    Thanks,

    Nick