While using MAX30102, if mode = 010 or heart rate mode, is one full sample 3 bytes only?

Question: If mode = 010 or heart rate mode, is one full sample 3 bytes only? Answer: In the heart rate mode the FIFO Data does contain 3 bytes per channel

Are the LEDs in the MAX30102 homogeneously transmitting light to the users skin, or is the transmission angle tapered internally?

The LEDs in the MAX30102 are not optically altered in any way to vary the transmission angle. We expect the LEDs to transmit homogeneously out of their encapsulation.

How can I get MAX30102 EVKit software including SKA and PBA algorithms source code?

ADI does not providing any source code for the MAX30102 algorithms including SKA and PBA.

MAX30102 Averaging Information

Question: If mode = 011 or SpO2, there are 2 sets of data (Red and IR) for one full sample. If SMP_AVE[2:0] > 0 in register 0x08, does the averaging number applies to individual channel independently? Answer: If SMP_AVE[2:0] > 0 in register 0x08, the averaging number does indeed apply to individual channel independently.

How do the algorithms used with the MAX30102 determine heart rate from the ADC data?

The max30102 determines heart rate by implementing algorithms that measure the systolic peaks intervals or R-R intervals of the PPG signal and the difference in time between these peaks. From this we can deduce heart rate in BPM.

What is related to the data interruption of the MAX30102?

The frequency of interruption of the MAX30102 data is related to the settings of the sampling rate and sampling average. For example, if the sampling rate is 400sps and the sampling average is 8, the frequency of interruption will be 50.

How to control the sample rate for heart rate mode in MAX30102?

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

Does the MAX30102 have an R-curve associated with it to correlate the ratio R = (ACred/DCred)/(ACir/DCir)?

MAX30102 does not have an R curve data associated with it as the R curve data is typically collected for (sub) groups of people (or animals) in a very controlled medical manner. Especially, if the SpO2 range extends to lower levels (e.g., 70-75%) that endanger life. We recommend purchasing a medical SpO2 device (3% accuracy) and use it as a calibration control unit.

What is the effective noise free resolution of the MAX30102?

The effective noise free resolution is 18-bits . Valid data starts from bit 17 and end at 3-0 depending on the resolution configuration, data found in bit locations higher than 17 can seem to represent valid data but are more susceptible to noise and will lead to erroneous data collection that would need to be corrected. You should configure the ADC resolution according to table 5 so that you can read the full range of current you expect the photodiode to produce in the first 15-18 bits.

Does the MAX30102 support I2C rapid communication mode?

According to the MAX30102 datasheet, the maximum I2C clock rate is 400KHz. They do not support clock rate at 1Mhz. However, the MAX30102 and MAX30101 have a maximum sampling rate of 3200sps; when reading data under burst mode, the effective data write/read speed is 9600 per second, which is 9.6kHz, so 400kHz is sufficient for the component.

What is the maximum altitude specification for the MAX30102?

There is no altitude specification for this device. However we have ~300 million units in the market as of today in smartphones and we haven’t received any altitude-specific concerns.

How do I use the shutdown (SHDN) function of MAX30102?

The most significant bit of Mode Configuration (0x09) register needs to be configured; setting it to logic high would put the part to shutdown, and setting it to logic low would put the part under normal operation. While in power-save mode, all registers retain their values, and write/read operations function as normal. All interrupts are cleared to zero in this mode.

Why does the PPG waveform observed through AFEs differ slightly from the PPG waveform found in medical texts?

PPG AFEs measure the PPG signal via the intensity of the light reflected into photodiodes, and as the blood volume in the arteries increases, following the contraction during the systolic phase, so does the absorption of the light being shined into the tissue. Since there is more absorption, the photodiodes will receive less reflected light and the output of the AFE will decrease. During the diastolic phase, while there is less blood in the arteries there will be less absorption and therefore more reflected light to the photodiodes. Hence the output of the PPG AFEs is just an inversion of the PPG plot that you find in medical texts.

The MAX30102ACCEVKIT GUI keeps crashing while trying to find the pba.dll file, but it is installed correctly, what could be the issue?

Please i nstall the relevant Microsoft Visual C++ redistribute package for your OS at the below link. https://www.microsoft.com/en-us/download/details.aspx?id=40784

Can MAX30102's internal temperature sensor be used to measure body temperature?

The temperature sensor on board the MAX30102 is not needed in Maxim's HRM/SpO2 algorithms. The temperature sensor was leftover from an older through-process. It is not an accurate temperature sensor so no, it should not be used to reliably measure body temperature. An external IC sensor should be used for any (skin contact, for example) temperature measurements, but, again, body temperature measurements are not needed for any of Maxim's HRM/SpO2 algorithms.

What areas of the body are popular for measuring heart rate and SpO2?

The finger is used for both transmissive and reflective heart rate and SpO2 measurements, the MAX3010X is a reflective device meaning the LED signal is reflected back to the device as opposed to having the Photodiode opposite to the LEDs. The wrist is commonly used in fitness and wearables which also uses a reflective method, it is recommended that green LEDs are used for the wrist when using the MAX30101. The MAX30102 should be used with both Red and IR for heart and SpO2 measurements. Hearable devices such as earbuds measure heart rate and SpO2 at the ear which has strong blood perfusion using Red and IR LEDs and the MAX86140. The foot is mainly used for infants heart rate and SpO2 using Red and IR LEDs using the MAX30102. The forehead can also be used for SpO2 acquisition using the reflective devices, MAX30102 or MAX30101.

Does MAX30102 require an extra cover glass? If we add one, what are the requirements?

It is recommended to add an external cover glass. The cover glass must guarantee over 90% transmission of red and infrared light. Otherwise, the signal quality will degrade and affect the performance of the final design.

Can you suggest any tester/simulator model for the MAX30102?

As per simulators, this is one of the devices we are aware of that does Reflective simulation of PPG signals ( https://www.whaleteq.com/en/product.php?act=view&id=20 ).

Has the MAX30101/MAX30102 been tested for biocompatibility?

The MAX30101/MAX30102 was never been designed to be in contact with human skin directly, and it always requires a cover glass or encapsulation material. IEC 62471 Photobiological safety has been done, which tests radiation hazard or retinal damage instead of biocompatibility of skin.

Can the IR sensor of the MAX30102 be used to measure body temperature?

Answer: No, the photodiode is optimized for the spectrum of the LEDs used. (The IR LED is 880 nm; the red LED is 660 nm.) Measuring body temperature requires a good response to wavelengths more than 10 times longer, which is not feasible using a silicon photodiode. If non-contact temperature measurement is required then a thermopile -based sensor would be better suited.