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AFE4490SPO2EVM: DB9 oximetry reflective mode

Genius 15159 points
Part Number: AFE4490SPO2EVM
Other Parts Discussed in Thread: AFE4490, , AFE44S30, AFE44I30, AFE4460, AFE4403EVM, AFE44S30EVM, AFE44I30EVM, AFE4403

Hi Experts,

I am seeing posts from over 7yrs ago about AFE4490 designing with reflective oximeter.

For our current AFE4490SPO2EVM, it comes with DB9 oximeter, but the sensor is in transmitting mode. I am looking for DB9 oximetry which is in reflective mode and compatible with the kit.

Can you suggest?

Regards,
Archie A.

  • Hi Archie, 

    As recommended in the AFE4490 datasheet, the AFE4490 is more focused towards transmissive SpO2 methods due to the number of LEDs and photodiodes supported. For something more focused towards reflective pulse oximetry, I recommend our more recent devices, such as the AFE44I30, AFE44S30, and AFE4460. These support the number of LEDs and photodiodes that are required for effective reflective pulse oximetry. 

    For a DB9-compatible AFE44xx EVM, I would recommend the AFE4403EVM https://www.biometriccables.in/products/spo2-extension-cable-compatible-with-hrmdb9-to-8pin 
    However, I would prefer you lean towards a more recent device such as the other AFE44xx devices mentioned above. 

    As a side note, could you let me know which customer you're supporting? What are their requirements for PPG and SpO2? 

    Kind regards,
    Nick Z

  • Thanks Nick, for your complete explanation.

    One more question. Is AFE4490SPO2 compatible with NONin 8000R?

    Regards,
    Archie A.

  • Hello Archie, 

    I understand that you're looking for a reflective SpO2 system. However, this application usually requires more photodiode inputs and LED inputs than what the AFE4490 can offer. Reflective SpO2 has both a lower amplitude and more noisy signal than transmissive SpO2, meaning that the extra photodiode inputs are essential.

    If the sensor has a DB9 connector in the pinout that's compatible with the EVM, it should work fine. However, looking at the Nonin 8000R specifications, I cannot find a pinout of the device, nor see the connector that it uses. I do not recommend trying to use this with the EVM. 

    My recommendation is to acquire an EVM that has reflective SpO2/PPG in mind. For a DB9-compatible EVM, I recommend the AFE4403EVM. For an EVM with superior performance to the AFE4403 but does not have a DB9, I recommend the AFE44I30EVM or AFE44S30EVM.

    Kind regards,
    Nick Z