3_1

3_1

Because the LCD screen is an instantaneous output, the MAX30102 sensor collects 4 seconds of data processing and outputs it together, causing data errors to be displayed on the LCD screen. So I changed the MAX30100 sensor to solve this problem. Because the MAX30100 sensor data is instantaneous output, it matches well with the LCD screen. The aim of this week is to test the optical sensor MAX30100 function.

Hardware requirement

1.     The optical sensor MAX30100

2.     Arduino Nano

3.     Three 4.7KΩ resistor

Software requirement

1.     Arduino 1.8-3

Connection requirement

MAX30100 sensor	Arduino Nano
VIN	5V
GND	GND
SCL	A5
SDA	A4
INT	D2

Figure 1: The circuit schematic for the MAX30100 sensor

The SCL and SDA pins are pulled-up via the 4.7k ohm resistors to 1.8V. This means it won't work well with microcontrollers with higher logic levels.

Figure 2: the connection circuit

Next, download the initial program to Arduino Nano and compile the program, the results can be seen in figure 3.

The figure 3: results from the Arduino Nano

Conclusion

It's worth noting that the sensor is not used on the Arduino Nano board directly, because of the limitation of working voltage for the sensor (MAX30100). We need pull-up the 4.7k ohm resistors between the SDA and SCL pins to reduced voltage to 1.8V.