• State
  • Locked Locked
  • Replies 1 reply
  • Subscribers 46 subscribers
  • Views 301 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.

ADS8332 does not do conversion

Alexander Panasyuk
Prodigy 40 points
Other Parts Discussed in Thread: ADS8332

Hello,

I need a bit of a help with  ADS8332. It is set to 0x7FD (no AUTO_CHANNEL, no TAGS) and communicates with processor (ATmega128, 20 MHz) just fine. Some time ago I've noticed that sometimes the chip suddenly switches into a mode when it stops doing conversions -  after CONVRT goes down EOC stays high and no conversion takes place, chip returns zeros (see diagram). CFR reads the same. Power cycle was bringing the chip out of this state.

Now power cycle does not help any more, chip communicates with processor fine but not doing conversions. 

Any suggestion would be appreciated,

Thanks,

Alexander.

  • 0
    TI__Guru 55466 points

    Hi Alexander,

    Sorry for the delay on the reply.  I would expect EOC to toggle low shortly after CONVST is pulsed low, and stay low during the conversion time (approximately ~1.500 us to ~1.7uS).  I assume the RESET pin is being set high while attempting to read data, is this correct? The plots provided are from a logic analyzer.  Is it possible to obtain oscilloscope shots zooming in to the SCLK signal?  It would be interesting to look if there is any overshoot/undershoot on the SCLK that may be causing issues.  Is this a PCB board or a proto board or using the ADS8332EVM? If you have an schematic showing the interface connections (CS, SDO, SDI, CONVST, EOC, and RESET connections) and the input driving circuit this also may be helpful.

    Thank you and Best Regards,

    Luis