Hi all, I have a confusion over choosing combination. I have scenario where I need to measure SPO2 reading from a photodiode. So here should I use a op-amp and amplify and feed it to a stm32 or use a HX710b and feed the digital signal to the stm32. Which one will be robust and reliable and can do repeated readings perfectly?

 

Either of your stated choices, and many other electronic configuration could be made robust enough to give repeatable readings, depending on the accuracy and resolution you require. The main problem will be how you are going to position the sensor to give reliable repeatable results.

 

Either of your stated choices, and many other electronic configuration could be made robust enough to give repeatable readings, depending on the accuracy and resolution you require. The big problem will be how you are going to position the sensor to give reliable repeatable results.

I need high accuracy and resolution, either way I can use IIR filter and do that I guess. But the thing which you said 'the position of the sensor', I didn't get this. Can you please elaborate it?

 

I need high accuracy and resolution, either way I can use IIR filter and do that I guess. But the thing which you said 'the position of the sensor', I didn't get this. Can you please elaborate it?

You didn't mention whether you are measuring the O2 levels in a sample or on a live subject.

 

You didn't mention whether you are measuring the O2 levels in a sample or on a live subject.

My bad, I meant to measure SPO2 of human. Probably at finger tip..

 

My bad, I meant to measure SPO2 of human. Probably at finger tip..

Then I will repeat: The main problem will be how you are going to position the sensor to give reliable repeatable results. The best you can hope for is about 2% accuracy.