• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 40 subscribers
  • Views 363 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.

TIDA-00168: Thermocouple Biasing and ESD Protection

Darren (FAE)
Expert 5483 points
Part Number: TIDA-00168
Other Parts Discussed in Thread: ESD321

This Reference design is really helping me support a customer. 

I understand from around Fig. 32 how to go about calculating the error due to bias currents, etc.

But I was wondering if there was any documentation/guide, or advice someone could provide, on how adding the ESD diodes affects the measurements? I know there is some leakage current...
I was hoping for some help on a setup with ESD diodes with/without surge-proof resistors...

Not really sure how to start going about calculating the error due to the diodes...

- Darren

  • 0
    TI__Expert 8471 points

    Hi Darren,

    The important thing to note about leakage current with ESD diodes is that you want to keep the normal voltage levels on the line at or below the Vrwm of the diode. Here is an article explaining this. If you look at the ESD321 datasheet, you'll see that the maximum leakage at Vrwm is 10 nA. However, if you increase the voltage to Vbr, the current through the diode will be 1 mA. 

    I'm not as familiar with surge proof resistors, but generally, the more you add components in parallel, the higher your leakage will be. 

    Let me know if this needs any clarification.

    Regards,

    Matt Smith