• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 47 subscribers
  • Views 391 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.

Original question:

ADS131M06: ADC Noise measurement to achieve resolution

ADS131M06: Noise floor level calculations

Deepak c
Prodigy 100 points

Part Number: ADS131M06

Hi Ryan,

Sorry i was away for Long time and busy with other things.

Actually i am sensing AC Voltage of 540V with upper resistor of 900K and Bottom resistor of 2K.

so at ADC i am getting 1.2V when 540V is applied.

For continuous operation i wanted to make sure resoultion of 1V is achieved (All the resistor used are 1% tolerance).

Could you please help me how i will get the noise floor level?

  • 0
    TI__Guru 69076 points

    Hello Deepak,

    With external AC voltage applied through a resistor divider, I would not expect the ADC noise performance to match the data sheet noise measurements (section 7). Our tests generally consist of input-short noise or full-scale sine waves from a clean, low-distortion function generator (i.e. an Audio Precision or similar). The reason we characterize the device this way is to showcase the best possible performance the ADC can achieve.

    However, 1 V through your resistor divider will translate to about 2.2 mV. Assuming Gain = 1, this equates to a signal amplitude of -54.67 dBFS. At Gain = 1, our minimum dynamic range is 92 dB, so this should not be a problem for our ADC. 

    Regards,

    Ryan