• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 47 subscribers
  • Views 351 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.

INA333: Bandwidth-limiting in a PT100 application

Adam Steele
Prodigy 160 points
Part Number: INA333

Tool/software:

I am using the INA333 in a PT100 reader circuit and only need good performance near DC. Is it possible to limit the gain bandwidth of the INA333?

  • +1
    TI__Mastermind 33061 points

    Hey Adam,

    Since the INA333 is a closed-loop device, there isn't really a way to directly limit the BW of the device. Technically, increasing the gain will lower the 3dB bandwidth, but this does not change the UGBW of the device. What benefit are you looking to realize by lowering the GBW? Increased noise performance?

    Best,
    Gerasimos

  • +1 in reply to Gerasimos Madalvanos
    Prodigy 160 points

    Hi Gerasimos,

    Yes that is correct. If i have some noise on the RTD cables, etc.. then it would be better if this were not gain'ed up. 

    In the absence of a way to limit the BW, then also given the high input impedance and low bias current requirements of the INA333 I can instead put some common mode filtering at the input. Maybe 10K on each input and 1 uF between them?