Hi Dharmesh, [quote userid="301387" url="~/support/data-converters-group/data-converters/f/data-converters-forum/1485066/ads1119-adc-selection-advice"]I would like to know if this device is suitable or if you would recommend a better alternative. The only requirement is that it must have an I²C interface and at least four channels. [/quote] I would recommend also taking a look at the ADS1115 data sheet, product information and support | TI.com , and at the ADS112C04 data sheet, product information and support | TI.com , which is a similar device that offers a h igher sample rate (2 kSPS), variable input range, iDACs, and internal temp sensor. The ADS1115 should be a good solution for your application. Is there a max sample rate requirement? [quote userid="301387" url="~/support/data-converters-group/data-converters/f/data-converters-forum/1485066/ads1119-adc-selection-advice"]Should I use 5V as my reference? Am I correct in understanding that since the REF is differential, the top reference value will be 2.5? [/quote] Correct, typically the max voltage that you can measure is equal to the reference voltage of the ADC. [quote userid="301387" url="~/support/data-converters-group/data-converters/f/data-converters-forum/1485066/ads1119-adc-selection-advice"]Should I include additional filtering, or would it be better to use the internal 2.048V reference? I do not expect my signal to exceed 2V.[/quote] I'm not sure what you mean by this question. You can use internal reference without issues if you don't expect your signal to exceed 2V. We recommend adding an anti-aliasing filter at the analog inputs of the ADC. See example: [quote userid="301387" url="~/support/data-converters-group/data-converters/f/data-converters-forum/1485066/ads1119-adc-selection-advice"]I plan to take readings multiple times per minute unless it is recommended to do so every few seconds and apply averaging. How do I determine the optimal data rate setting? Since the ADC is Delta-Sigma, I believe it performs oversampling and filters outliers—am I correct?[/quote] If you don't have a sample rate requirement, using the lowest data rates results in the lowest noise due to the higher over sampling rate. You can learn more about the delta-sigma ADC operation from our TIPL video series: Precision labs series: Analog-to-digital converters (ADCs) | TI.com [quote userid="301387" url="~/support/data-converters-group/data-converters/f/data-converters-forum/1485066/ads1119-adc-selection-advice"]Since the device has a gain setting, would it be advisable to initially take a sample at gain 1 and, if the voltage is below 0.5V, switch to gain 4 for better resolution? Is this a recommended practice, or should I keep the gain at 1 for my application?[/quote] You can change the gain settings for the different ADC sensor readings to improve dynamic range. Ultimately you have to decide what makes sense for your application and sensor measurements, gain of 1 may be good enough for your purposes. Best Regards, Angel
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