I am working with the MAX30100 and MAX30102 Blood Oxygen SPO2 Detectors trying to get them to work. First I bought the MAX30100 and then later the MAX30102 but they did not work. I have tried several libraries to no avail. Then, finally, I came across the issue that the 4.7K pull up resistors are tied to 1.8 volts and they are not high enough for a five volt processor.
The first solution is to remove the three 4.7K resistors (marked 472 in the picture) and replace them with external 4.7K resistors to 3.3 or even 5 volts. The second solution is to cut the run connecting them to 1.8 volts and jumper them over to the 3.3 volt regulator. The run to cut is marked in yellow in the following picture and then add the jumper marked in red.