ultraviolet light sensor

The VEML6075 senses UVA and UVB light and incorporates photodiode, amplifiers, and analog / digital circuits into a single chip using a CMOS process. When the UV sensor is applied, it is able to detect UVA and UVB intensity to provide a measure of the signal strength as well as allowing for UVI measurement.

The VEML6075 provides excellent temperature compensation capability for keeping the output stable under changing temperature. VEML6075’s functionality is easily operated via the simple command format of I2C (SMBus compatible) interface protocol. VEML6075’s operating voltage ranges from 1.7 V to 3.6 V.

Shopping List

Schematics/Layout

microbit and VEML6075

Code

Again we use a library  – https://github.com/NorthernWidget/VEML6075

[codesyntax lang=”cpp”]

[codesyntax lang=”cpp”]

#include <VEML6075.h>

VEML6075 UV;

void setup()
{
Serial.begin(38400); //Begin Serial
UV.begin(); //Begin the UV module

}

void loop()
{
Serial.print("UVA = ");
Serial.print(UV.GetUVA()); //Get compensated UVA value
Serial.print(" UVB = ");
Serial.println(UV.GetUVB()); //Get compensated UVB value
delay(1000);
}

[/codesyntax]

Output

Open the serial monitor – this is what I saw

UVA = 0.00 UVB = 3.00
UVA = 0.00 UVB = 0.00
UVA = 0.00 UVB = 1.00
UVA = 0.00 UVB = 2.00
UVA = 0.00 UVB = 1.00
UVA = 0.00 UVB = 3.00
UVA = 0.00 UVB = 1.00
UVA = 0.00 UVB = 1.00

Links

https://www.vishay.com/docs/84304/veml6075.pdf

I2C Interface 3.3V Board Based on VEML6075 UVA UVB Light Sensor Module

VEML6070 is an advanced ultraviolet (UV) light sensor with I2C protocol interface and designed by the CMOS process. It is easily operated via a simple I2C command. The active acknowledge (ACK) feature with threshold windows setting allows the UV sensor to send out a UVI alert message.

Under a strong solar UVI condition, the smart ACK signal can be easily implemented by the software programming.

VEML6070 incorporates a photodiode, amplifiers, and analog / digital circuits into a single chip. VEML6070’s adoption of FiltronTM UV technology provides the best spectral sensitivity to cover UV spectrum sensing. It has an
excellent temperature compensation and a robust refresh rate setting that does not use an external RC low pass filter.

VEML6070 has linear sensitivity to solar UV light and is easily adjusted by an external resistor. Software shutdown mode is provided, which reduces power consumption to be less than 1 μA. VEML6070’s operating voltage ranges from 2.7 V to 5.5 V.

Shopping List

Schematics/Layout

microbit and VEML6070

Code

No libraries in this example

[codesyntax lang=”cpp”]

#include <Wire.h>

// VEML6070 I2C address is 0x38(56)
#define Addr 0x38

void setup()
{
  // Initialise I2C communication as MASTER
  Wire.begin();
  // Initialise serial communication, set baud rate = 9600
  Serial.begin(9600);
  
    // Start I2C Transmission
    Wire.beginTransmission(Addr);
    // Select command register
    // Integration time = 0.5T, shutdown mode disable 
    Wire.write(0x02);
    // Stop I2C Transmission
    Wire.endTransmission();
  delay(300);
}

void loop() 
{
  unsigned int data[2];
  
  // Start I2C Transmission
  Wire.beginTransmission(Addr);
  // Select data msb register
  Wire.write(0x73);
  // Stop I2C Transmission
    Wire.endTransmission();
    
  // Request 1 byte of data
  Wire.requestFrom(Addr, 1);
  
  // Read 1 byte of data
    if(Wire.available() == 1)
    {
    data[0] = Wire.read();
    }
    
  // Start I2C Transmission
  Wire.beginTransmission(Addr);
  // Select data register
  Wire.write(0x71);
    // Stop I2C Transmission
    Wire.endTransmission();
    
  // Request 1 byte of data
    Wire.requestFrom(Addr, 1);
    
    // Read 1 byte of data
    if(Wire.available() == 1)
    {
        data[1] = Wire.read();
    }
  
  // Convert the data
  float uvlight = data[0] * 256.0 + data[1];
  
  // Output data to serial monitor
    Serial.print("UV Light Of The Device");
    Serial.println(uvlight);
    delay(1000);     
}

[/codesyntax]

Output

Open the serial monitor – this is what I saw. I was indoors at the time

UV Light Of The Device0.00
UV Light Of The Device0.00
UV Light Of The Device0.00
UV Light Of The Device0.00
UV Light Of The Device0.00
UV Light Of The Device0.00

Links

https://www.vishay.com/docs/84277/veml6070.pdf

VEML6070 UV Sensitivity Detection Sensor for Arduino