• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Subscribers 46 subscribers
  • Views 557 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

DAC121S101QML

James Johnson2
Prodigy 20 points
Other Parts Discussed in Thread: DAC121S101, LM4050QML-SP

I'm interested in using the DAC121S101QML in a space application.  The requirements include -20 to 60 deg C environment, a +/-10V range, 12-bit monotonicity, <+/-0.1% FS (0.020V) linearity error, and <0.2% FS (0.040V) total error.  The datasheet gain error tempco is given as 'typical'.  Are absolute min/max numbers available?  Can you provide a second opinion about whether or not this device will meet these requirements and total error calculated.  Please assume 0 error for supporting circuitry and gain and offset errors initially zero'd out.  I will use a 5V reference/supply, bipolar output connection and a following 2x gain stage.  I'm comparing this to an AD768S, so any comparisons you can make would also be appreciated. Thank you. JPJ

  • 0
    TI__Genius 17125 points

    Hello James,

    Attached are gain error and full scale error raw data for 49 units (in ppm) and tempcos (in ppm/C).   I apologize for the presentation but this was the quickest way to get you data.

    As you can see, the distribution is much tighter than the limits and there is very little shift over temperature. 

    Between this part and the AD768S depends upon what is important to the application.   The DAC121S101QML only operates off of a single supply.   The AD768S uses about 1000 times more power than the DAC121S101.

    For a 5V reference/supply, I would like to suggest the space grade LM4050QML-SP.

    DAC121S101 Gain Error over temp.pptx

  • 0 in reply to Kirby Kruckmeyer96848
    Prodigy 20 points
    Hello Kirby,
    Thanks for the information. Could I ask for one example of interpreting the data you provided so I can make sure I understand it correctly.
    Thanks again.
    JPJ
  • 0 in reply to James Johnson2
    TI__Genius 17125 points

    If I understand your question correctly:

    Page 2 shows the gain error with supply voltage at 5.5V for 49 parts.

    On unit #1, gain error at -55C is -162 ppm of full scale range, at +25C -167 ppm and at 125C, -169 ppm.

    Divide the numbers by 1000 to put the data in terms of % of full scale range as the limits are listed in the datasheet.

    The tempco  for of the gain error for unit 1 for the temp range of --55C to +25C is -0.07 ppm/C and the tempco for the temp range of +25C to +125C is -0.02 ppm/C.