• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 46 subscribers
  • Views 378 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.

DAC9881: Glitch Reduction

Martin Stougaard
Prodigy 120 points
Part Number: DAC9881

Hi

I am considering using an external S/H switch in a DAC-application running 18 or 20 bits.

I have read the document "http://www.ti.com/lit/ug/tidu022/tidu022.pdf"

of Matthew Sauceda.

Is the switch controlled so that you not is turning it on/off when non-major codes are loaded - and how? From an output of a microcontroller?

Is the sample/hold-switch circuit too noisy to operaing always at all codes?

regards Martin

  • 0
    TI__Mastermind 46290 points
    Hello Martin,

    Largely the TI Design is intended to discuss the analog content. The software implementation would be up to the user. Concerning the reduction in glitch the document uses the mid-scale major carry transition as the code for showing the glitch reduction since this should be the worst case. If you wanted you could implement some intelligence for the switch such that it is only implemented for major carry transitions.

    On the other end of the spectrum, you could also choose to enable the S+H action for all codes. There should not be any significant noise impairment compared to the results shown for the major carry transition in the document.