Microbit and GUVA-S12SD UV Sensor
The GUVA-S12SD UV Sensor chip is suitable for detecting the UV radiation in sunlight. It can be used in any application where you want monitor for the amount of UV light and is simple to connect to any microcontroller. I recently noticed that some sellers had little modules for this sensor at a reasonable price so decided to purchase one
The module, with a typical UV detection wavelength of 200 – 370nm, outputs a calibrated analog voltage which varies with the UV light intensity so basically all you need to do is connect this to an ADC input and read in the value.
This value ties in with the UV index, this looks something like this
Connection
The connections are straightforward and described below, I used 3.3v from my Micro:bit. This was mainly for compatibility with other development boards but the module works with 5v.
1. GND: 0V (Ground)
2. VCC: 3.3V to 5.5V
3. OUT: 0V to 1V ( 0 to 10 UV Index)
Layout
Code
Simple code example that reads the value at A0 and outputs the results via the serial monitor
sensorVoltage = sensorValue/1024*3.3;
[codesyntax lang=”cpp”]
void setup()
{
Serial.begin(9600);
}
void loop()
{
float sensorVoltage;
float sensorValue;
sensorValue = analogRead(A0);
sensorVoltage = sensorValue/1024*3.3;
Serial.print(“sensor reading = “);
Serial.print(sensorValue);
Serial.println(“”);
Serial.print(“sensor voltage = “);
Serial.print(sensorVoltage);
Serial.println(” V”);
delay(1000);
}
[/codesyntax]
Testing
Open the serial monitor and look at the readings
sensor reading = 46.00
sensor voltage = 0.15 V
sensor reading = 46.00
sensor voltage = 0.15 V
sensor reading = 46.00
sensor voltage = 0.15 V
sensor reading = 46.00
sensor voltage = 0.15 V
sensor reading = 46.00
sensor voltage = 0.15 V
If you look at the image earlier that corresponds to UV index of 0
