• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 46 subscribers
  • Views 237 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.

ADS1234: No "Data Ready"

Scott Hudis
Prodigy 150 points
Part Number: ADS1234


Problem:
I am bringing up a new hardware design and as part of the debug process I applied power some time later I bring up the PD line and I expect some time later to get a data conversion ready. Have I missed an initialization step? My gains are both set to 1, My A0/A1 channels are set to 0. Should I see a conversion done.

Solution:

I design my boards with a star point connection to provide better control of the analog and digital ground connections.  I forgot to connect the grounds so in effect the analog ground was floating.  By the way if this happens you never get a data ready :).

  • 0
    TI__Mastermind 48240 points

    Hello Scott,

    If I understand your post, you have solved your problem and the ADC is now converting.

    Just to confirm, if the device is properly powered up, you should see /DRDY toggling at the output data rate with a high time of 39uS.  If you do not see this, then I would verify that the CLK is operating at the proper frequency, 4.9152MHz typical.  If you connect pin 3 low, this will enable the internal oscillator, which may be helpful to debug.

    Yes, both digital and analog ground pins must be connected to the same ground, next to the IC package for best performance.

    Regards,
    Keith Nicholas
    Precision ADC Applications