Hi
We have questions about INA226Q1.
1. What is the purpose of filtering at ADC input? Is this filter needed anytime?
2. Can we change the full-scale range of Bus voltage (40.96V)?
BestRegards
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.
Hi Mayrim,
what is the ADC specific(to consider) time during the signal have to be stable to be measured? I have to measure dynamics currents on my MCU. I know about the conversion times, but my question is focusing in to fastest measures, If ADC conversion time is 140us, how long the ADC take to get the value before convert and write all register(shubtV,BusV,current...)?
thank you in advance.
Ricardo.
Hi Ricardo,
I apologize for the delay. The INA226 is a low bandwidth device (only about 400Hz according to figure 1 of datasheet) that is intended for precise DC current measurements. So to begin with I would not recommend it for your application. Also, input signal stability during sampling is not a major concern with this device because of the relatively low input switching frequency (max 650kHz according to section 7.4.2). Even with a sampling cap value of 10pF (gross over-estimate) the input impedance would be about 24kOhm, which would result in less than 0.05% input voltage droop with a 10ohm source resistance. In addition, adding a large 0.1uF to 1uF input bypass cap, as recommended in the datasheet, will decrease the source impedance at high frequencies and reduce the droop even further.
Best Regards,
Harsha Munikoti