Question: How to control the sample rate for heart rate mode in MAX30102?
Answer: The maximum sample rate for the ADC depends on the selected pulse width, which in turn, determines the ADC resolution. For instance, if the pulse width is set to 69µs then the ADC resolution is 15 bits, and all sample rates are selectable. However, if the pulse width is set to 411µs, then the samples rates are limited. The allowed sample rates for both SpO2 and HR Modes are summarized in the Table 11 and Table 12 of the datasheet.
Table 7 of the datasheet has further information on setting the LED Pulse Width Control