Calculate O2 Saturation from AFE4490 Data

Robert Learney

Other Parts Discussed in Thread: AFE4490

Hello,

I've managed to set up and communicate with the AFE4490, and retrieve appropriate-looking data from my pulse oximetry setup (see attached image).

I just need a little help understanding how to move to the next stage of my project, which is to use the data from the AFE4490 to calculate the oxygen saturation. The standard method relies on log ratios of the RMS signal levels to their DC levels (attached)6371.Red-IR Ratio.tiff 3581.Left first finger - new timings.tiff. However, I don't know how to get the DC level out of the AFE4490 in order to perform this calculation. Do you perform the calculation a different way with the AFE4490?

Do you have any code or other resources to explain how you are able to extract a saturation value from the AFE4490's data? I'm using the reflectance-based DCM03 sensor, which I understand is the same module used in your HealthTech document dated the 27th August 2013.

Many thanks,

-Rob.

over 12 years ago

0 Amy Schnoor over 12 years ago

TI__Mastermind 18305 points

Robert,

You can request the source code of how we calculate the oxygen saturation from this site http://www.ti.com/tool/tida-00010#Technical Documents. Click on "TI Health Hub Evaluation and Demonstration Software Request". Hope this helps you move to the next stage of your project.

0 Robert Learney over 12 years ago in reply to Amy Schnoor

Intellectual 280 points

Thank you very much Amy,

I've gone through and completed the request as advised.

All the best,

-Rob.

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Calculate O2 Saturation from AFE4490 Data