Max30100(SpO2 sensor) with PSOC 4 BLE

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Anonymous
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Hi, I'm working on an implementation of Max30100 sensor with my PSOC 4 BLE kit. As mentioned in the datasheet I am getting 4 bytes of data. First two bytes represent IR values, while the next two represent Red values. But I am unable to understand which one is for AC level and which is for DC?

Datasheet of Max30100 - https://datasheets.maximintegrated.com/en/ds/MAX30100.pdf

Psoc project file -

9194.jpgspo2_data.PNG

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Anonymous
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The chip does not give values for AC versus DC, it gives voltage readings at the specified rate for the IR/Red readings. You will need to process the data from the raw ADC voltage readings into separate AC/DC values in order to calculate your heart rate measurement, and will need to deal with the calculations that that entails.

Based on these documents:

http://www.mnkjournals.com/ijlrst_files/Download/Vol%203%20%20issue%205/27-31-20102014%20An%20Overvi...

http://www.ti.com/lit/an/slaa655/slaa655.pdf

And the datasheet for the sensor: https://datasheets.maximintegrated.com/en/ds/MAX30100.pdf

I tried running some of the calculations in an excel sheet, but I must be doing the math wrong, or missing something, as the oxygenation levels are too low. But, either way I believe the values from the sensor are only raw data and need to be processed before use. The AC component I took to be the difference between the maximum and minimum measurements on the data, and the DC is the average of the data measurements. Also, it would seem that the data is stored/output as High Byte, Low Byte, but it is weird that the low bytes are not changing much. Also, unless you are setting up the Maxim sensor before reading values, it could be set in the wrong mode/settings as well.

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