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DAC5681 / INL,DNL, offset and gain drift

Ryuji
Guru 20090 points
Other Parts Discussed in Thread: DAC5681
Hello,
INL, DNL , offset drift and gain drift of the DAC5681 is specified at the condition of over operating free-air temperature range.
Will these parameters be improved at the narrow temperature range(for example +30°C~+40°C)?
If yes, could I have the improved data at the above condition?

Best Regards,
Ryuji
  • 0
    Guru 20090 points
    Hello,
     
    Would you please let me know the historam or the characteristics of at fixed temperature (Ta=+30C~+50C) of  INL,DNL,offset drift and gain drift? 
    Our customer is searching the DAC which has the following specifications.
    Since I can't find the device which satisfy the following specifications,  I suggested DAC5681 as close device to them.
     
    <Request>---------------------------------------
    Resolution:16bit
    Ta=+30C~+50C
    INL=<+/-4SLB(max)
    DNL=<+/-4SLB(max)
    Gain Drift =<10ppm(max)
    Offset Drift =<10ppm(max)
    Sampling Rate >10MSPS
    --------------------------------------------------------
     
    Then they request above data.

    Best Regards,
    Ryuji
  • 0 in reply to Ryuji
    TI__Genius 17310 points

    Hi Ryuji,

    We do expect these parameters to have a tighter range over a smaller temperature range (e.g. 30C to 50C), however I have no data to back it up. I would expect that we're very close or better than the customer's requirements over this narrower temperature range.

    From the designer: 

    INL/DNL will definitely be better in the 30 to 50C range because most of the drift in mismatch comes from the change in Gm and Vt over temperature.  If you hold the temperature more constant, then these mismatches won’t change as much.  Also, the bandgap reference, which affects the gain, has a temperature coefficient which also will be better over a tighter temp range.

    Regards,
    Matt Guibord

  • 0 in reply to Matt Guibord
    Guru 20090 points
    Hello Matt san,
     
    Thank you for your reply and sorry for my late reply.
    I consulted with my customer and as a result I got the following questions from them.
     
    (1) accuracy of external reference for Gain drift specification
    Could you please let me know the acuracy of external reference for Gain Drift Specification ?
    Gain drift is specified by external and internal reference.
    However there is no acuracy of external reference.
     
    (2) Gain drift with 1ppm/°C external reference
    Could you please let me know the gain drift specification with 1ppm/°C external reference?
    My customer use 1ppm/°C external reference for DAC5681.
     
    (3)Glitch impulse
    Could you please let me know the glitch impulse of DAC5681?
    LTC166x has the glitch impulse data as 5pV-s.
     
    Best Regards,
    Ryuji Asaka
  • 0 in reply to Ryuji
    Guru 20090 points

    Hi Matt san,

    Any update on this ?
    Our customer need these answer for using this device.

    Best Regards,
    Ryuji

  • 0 in reply to Ryuji
    TI__Genius 17310 points

    Hi Ryuji-san,

    Initial measurements show that the gain drift is worse than listed in the datasheet. Still working to confirm.

    Regards,
    Matt Guibord

  • 0 in reply to Matt Guibord
    Guru 20090 points
    Hello Matt san,

    Thank you very much for your checking.
    I'll be waiting for your confirming.

    Best Regards,
    Ryuji
  • 0 in reply to Ryuji
    Guru 20090 points
    Hello Matt san,
     
    Any update on this ?
    If you have some reply about the following questions, please let me know.
     
    -----------------
    (1) accuracy of external reference for Gain drift specification
    Could you please let me know the acuracy of external reference for Gain Drift Specification ?
    Gain drift is specified by external and internal reference.
    However there is no acuracy of external reference.
     
    (2) Gain drift with 1ppm/°C external reference
    Could you please let me know the gain drift specification with 1ppm/°C external reference?
    My customer use 1ppm/°C external reference for DAC5681.
     
    (3)Glitch impulse
    Could you please let me know the glitch impulse of DAC5681?
    LTC166x has the glitch impulse data as 5pV-s.
    -----------------
     
    Best Regards,
    Ryuji