• State Resolved
  • Locked Locked
  • Replies 4 replies
  • Subscribers 45 subscribers
  • Views 180 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

DAC11001B：How temperature drift calibration works？

Tianru Cao
Part Number: DAC11001B

I have recently been researching the performance and settings of the DAC11001B component. There are two functions in the datasheet that are not explained very clearly.

1. the temperature drift calibration. The datasheet only mentions how to calibrate by writing certain registers, but it does not explain how it works. Can you please explain how the temperature drift calibration works?

2. TNH_MASK Bit. What the difference of those 4 selection? 

Mask track and hold (TNH) circuit. This bit is writable only when FSET = 0
[fast-settling mode] and DIS_TNH = 0 [track-and-hold enabled]
00: TNH masked for code jump > 2^14 (default)
01: TNH masked for code jump > 2^15
10: TNH masked for code jump > 2^13
11: TNH masked for code jump > 2^12

  • +1
    TI__Expert 3310 points

    Hi,

    I will contact the designers to get more information about the temperature drift calibration for you.

    For TNH, when making small code jumps, the output is latched to help it not be affected by glitch voltage as much, which slows the update rate. This is disabled for larger code jumps, which the cutoff value is specified by the TNH_MASK bits that you provided. Let me know if this explanation is satisfactory.

    Thanks,
    Lucas

  • +1 in reply to Lucas Burnette
    TI__Expert 3310 points

    Hi,

    I have more information about the temperature drift calibration.

    During production, the device is trimmed at two temperature, which is saved in the device registers. When a temperature calibration occurs, the device measures the temperature and interpolates coefficients from the saved information. After recalibration, a write must be issued for it to come into effect. The designers advise to recalibrate when the temperature changes 5 C, but the device should be relatively accurate up to a 10 C change.

    Let me know if you have any further questions,

    Thanks,
    Lucas

  • 0 in reply to Lucas Burnette

    Thank you for your reply.

    According to your answer, I find there are three temperature coefficients in the datasheet: Zero code error, gain error and Full-scale error temperature coefficients.

    Can I understand your explanation by this way: The DAC contains the above three temperature coefficient registers, which will be updated after a temperature drift calibration occurs? 

  • 0 in reply to Tianru Cao
    TI__Expert 3310 points

    Hi,

    Yes, that is correct.

    Thanks,
    Lucas