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OPA2171-Q1: Voltage output swing long term drift

Arie Li
Expert 3390 points
Part Number: OPA2171-Q1
Other Parts Discussed in Thread: OPA2171

Hi Experts,

For below output voltage swing range of OPA2171-Q1, is it guaranteed in whole life time under -40-125C temperature range? Due to the aging of the components, will it cause additional long-term drift of this spec? Thanks.

OUTPUT

VO       Voltage output swing from rail (over temperature)              RL = 10 kΩ AOL ≥ 110 dB                        (V–) + 0.35                (V+) – 0.35              V

  • 0
    TI__Guru**** 155126 points

    Arie,

    I do not expect aging to effect that parameter significantly. The AOL part infers that the output transistor gate drive is not fully applied. Therefore more gate drive is in reserve.

     

  • 0
    Guru 140200 points

    Hi Arie,

    see this very nice article:

    Kai

  • 0 in reply to kai klaas69
    TI__Expert 3390 points

    Hi Kai,

    Thanks for sharing this article. From this article, the life time shift have two types:

    • Specifications centered around zero or a mean value (like Vos, Vos Drift, Vref, AOL, CMRR, PSRR, etc.) may shift over 10-year life up to:

                                 +/-100% of the max (min) PDS specified value

    • Specifications defined as an absolute value (like IQ, slew rate, Isc, etc.) may shift over 10-year life up to:

                                 +/-10% of the max (min) PDS specified value

    Which type does the output voltage swing belong to? If it belongs to the first one, so the long-term drift is within 100%, does it mean the output voltage swing of OPA2171 will become (V-)+0.7 to (V+)-0.7? The datasheet spec is (V-)+0.35 to (V+)-0.35

  • 0 in reply to Arie Li
    TI__Guru**** 155126 points

    Arie,

    Output swing would be in the second category. 

    The first category applies to parameters that are based heavily on component to component matching. Output swing does not require matching.  

  • 0 in reply to Ron Michallick
    TI__Expert 3390 points

    Hi Ronald,

    Thanks for your guidance. Could you please help to check if my below understanding is correct? Thank you so much.

    The output voltage swing of OPA2171-Q1 is (V-)+0.35 to (V+)-0.35 in datasheet, it does not include the long-term drift. If we take long-term drift into consideration, we can guarantee 110% of the datasheet spec, which is (V-)+0.385 to (V+)-0.385. Is it correct?

  • 0 in reply to Arie Li
    Guru 140200 points

    Hi Arie,

    what is the maximum ambient temperature in your application? +125°C? For a longer period?

    Kai

  • 0 in reply to Arie Li
    TI__Guru**** 155126 points

    Arie,

    110% of the datasheet spec, which is (V-)+0.385 to (V+)-0.385 is a good 'rule of thumb'. However, that is not a guarantee.

    The term '10 year life' is under a reasonable temperature. At high temperatures the '10 year life' shrinks quite a bit.