Best Reference for Long Term Drift and Hysteresis

Good Day,

We are searching for a voltage reference for a ruggedized data acquisition system.  The reference in each device will be characterized over temperature, so absolute accuracy and temperature drift aren't the primary concerns.  We can calculate those out.  We are looking for the best device in terms of long-term drift and thermal hysteresis.  A heated reference is not a good option, as our temperature profile is too wide.  These devices will be operated from -55 to 125C.

The output voltage isn't critical either - we can work with anything from 1.25V to 5V.

Obviously, something in the LS8 package or a thru-hole hermetic package is likely.

What reference would Analog suggest for this application?  LT6654 or LT6656 both seem like good choices, but perhaps there's something better?

Thank You,
Ben

  • 0
    •  Analog Employees 
    on Oct 4, 2021 1:59 AM

    Hi Ben,

    LT6654 and LT6656 are the best choice in your application. I found some other that fall on your requirement but output voltage are above 5V.

    I just want to remind you though that LT6656 are only fully specified at -40 to 85degC. This means that the specification that we have on the datasheet will not held true when this part is run -55 to 125degC.

    Regards,

    Mon

  • Mon,

    Thank you.  I actually missed that the 6656 was only specified to 85 - not sure how I skipped over such an important detail, but I sure did.

    I'm interested to know what references you feel might be better choices, even if they're above 5V.  I can make minor design changes to support higher output if it's worthwhile for better stability.

    Thank you.

  • 0
    •  Analog Employees 
    on Oct 4, 2021 4:28 AM in reply to AeroBen

    Hi Ben,

    6656 can take -55 to 125degC operating Temperature. So it might be that's what you see.

    We have AD587, LT1031 and LTZ1000.

    AD587 and LT1031 is comparable with LT6654 in terms of Specifications.

    LTZ1000 is better in terms of long term drift.

    Regards,

    Mon