• State TI Thinks Resolved
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 45 subscribers
  • Views 33 views
  • Users 0 members are here
Support feedback
Options
Options
Related

ADS131B26-Q1: ADS131B26-Q1 GPIO trigger ADC sampling

Xiaoqiang Sun
Prodigy 230 points
Part Number: ADS131B26-Q1


Hi,

To sync the ADC sampling time with MCU, I want to trigger the sampling as I need.

I read the datasheet, it says "Setting the STARTy bit while conversions
are ongoing on an ADC aborts the ongoing conversion and restarts conversions."

It looks like I can only tigger it via send command from SPI. What is the frequency of SPI clock?

Can I configure the GPIO to input and trigger the ADC sampling start via this GPIO?

  • 0
    TI__Mastermind 23615 points

    Hi Xiaoqiang,

    unfortunately the ADS131B26-Q1 does not provide a START or SYNC pin to start conversions using a pin.
    You can only start or synchronize conversions by writing to the START bit through SPI.
    The maximum SPI frequency that you can use is specified by the tc(SC) parameter in the Timing Requirements table.

    Attached is some presentation I had put together previously to explain how you could time the sending of the START bit to get conversions started at a specific time.

    ADS131B2x-Q1 - Conversion Synchronization.pdf

    Regards,
    Joachim Wuerker