Pulse oximeter circuit: Help

[Precious1]

Hi everyone!
Can someone help me with the working circuit of pulse oximeter? I have tried to look at different circuits and I am just getting confused more and more; as I have read algorithms for calculating pulse rate and SPO2 I hope I can manage the code part. Please help

 

[amayilsamy]

This forum link having details about SPO2 Design basics.

https://www.edaboard.com/threads/95352/

I hope its helps you.

 

[Precious1]

Thanks Amayilsamy.
I have gone through the link even before, I don't find it helping me. That's why now I need a circuit. So please if you have one

 

[BradtheRad]

There have been several threads here, which will turn up by doing a search on 'oximeter' or 'blood'.

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In my mind the hard part is to attach a sensor which is sensitive enough to detect blood color, intensity, etc., under the skin.

Some combination of a phototransistor (or photodiode), plain light or infrared, hue filtering, etc.

And sufficient amplification.

Maybe also the ability to compare blood intensity during a pulse to intensity between pulses, etc.