Description:    The MAX30102 is an integrated pulse oximeter and heart rate monitor biosensor module. It integrates a red LED and an infrared LED, photodetector, optical device, and low-noise electronic circuitry with ambient light suppression. The MAX30102 uses an 18V power supply and a separate 50V power supply for internal LEDs. Wear the device for heart rate and blood oxygen collection, and wear it on your fingers, earlobe and wrist. The standard I2C-compatible communication interface can transfer the collected values to the Arduino, KL25Z and other microcontrollers for heart rate and blood oxygen calculation. In addition, the chip can also shut down the module through software, the standby current is close to zero, and the power supply is always maintained. Because of its excellent performance, the chip is widely used in the Samsung Galaxy S series mobile phones. The chip integrates a glass cover to effectively eliminate external and internal light interference and has the best reliable performance.    Parameter:    LED peak wavelength: 660nm/880nm  LED supply voltage: 3.3-5V  Detection signal type: light reflection signal (PPG)  Output signal interface: I2C interface  Communication interface voltage: 18-3.3V-5V (optional)  Board reserved assembly hole size: 0.5X8.5mm  Working principle: Light-dissolving method: measuring the pulse and blood oxygen saturation by using human tissue to cause different light transmittance when the blood vessel beats; Light source: a specific wavelength illuminating pole tube selective for oxyhemoglobin (HbO2) and hemoglobin (Hb) in arterial blood; Transmittance is converted into electrical signal: the volume of the arterial pulsation is changed to the light transmittance of the light. At this time, the light is reflected by the human body tissue by photoelectric conversion, converted into an electrical signal and amplified and output.    Pin Description:    VIN: main power supply input terminal 1.8V-5V; 3-bit pad: Select the pull-up level of the bus, depending on the pin master voltage, select 1.8v or 3.3V (this terminal contains 3.3V and above)  SCL: Connect the clock of I2C bus;  SDA: data connected to the I2C bus;   INT : Interrupt pin of the MAX30102 chip;   RD: RED of the MAX30102 chip, LED ground terminal, - generally not connected;   IRD: The IR, LED grounding of the MAX30102 chip is generally not connected;  GND :Ground wire    Package Included:   1 x MAX30102 Heart Rate Sensor Module