Dear team,
Here is a question from the customer.
They read back the data through I2C every 500ms. The conversion period of our chip is about every 500us. So, there are about 100 samples during a read period. So what will I get when reading back data? The average value of these 100 samples? Or RMS of these 100 samples? Or just the last value of these 100 samples?
best regards,
Lijia Zhu
Hello Lijia,
Thanks for reaching out on the forum. What you get depends upon the settings you use in the configuration register. The particular settings you need to consider for this question are labeled as BADC and SADC (register bits 3-10). Depending on how configure these bits, the INA220 conversion time could be as little as 84us or 532us. Assuming you are wanting 12 bit resolution, the minimum conversion averaging time could be as little as 532us (1 sample) or as much as 17.02ms (32 samples). If you choose the 1 sample setting, the data you read back will always be the last value. If you choose any of the multi-sample options, you will get an average. The most samples the INA220 will average before beginning another averaging set is 32. The table below should help clarify your options.
