• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Answers 1 answer
  • Subscribers 46 subscribers
  • Views 298 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.

ADS1292: Channels interfere with each other

Ryan Chan
Prodigy 20 points
Part Number: ADS1292

Hi!

I am currently trying to use an ADS1292 to read EMG signals. After connecting 2 electrodes from a muscle to IN1P and IN1N and a third electrode from my elbow to ground like in this guide, I was able to get pretty good raw data from channel 1 as expected. However, when I read channel 2 with no electrodes connected to it, I discovered that channel 1 interfered with channel 2 significantly. Here’s a video of the raw data where the blue is channel 1 and red is channel 2 (https://youtu.be/iw_7iULqlTM). I was wondering if anyone might have any idea on what might be causing channel 1 to interfere with channel 2? Thank you!

Edit: here is the schematic of the PCB for a bit more context

:

  • +1
    TI__Genius 11550 points

    Hi Ryan,

    Welcome to the E2E forum !!!

    The input to the device has a very high input impedance (GOhms), which may cause some noise coupling from different sources. The channel crosstalk for the device is specified at -120 dB typically, so it is unlikely to be the device issue itself. In the video, you can see some oscillation in CH2 data even without any EMG signals. Typical, all the INP and INN should be at the common-mode voltage level and not be left floating.

    Thanks

    -TC

  • 0 in reply to TCT
    Prodigy 20 points

    Hi TC,

    Thank you for the response! It is very helpful and I will test it again without leaving channel 2's INP and INN floating like I did in video.

    Best,

    Ryan