Design with Adafruit LTR390 UV Light Sensor in Cirkit DesignerThe Adafruit LTR390 UV Light Sensor is a precision sensor module capable of detecting ultraviolet (UV) light and ambient light. It provides accurate UV index readings, which are essential for monitoring exposure to ultraviolet radiation. This sensor is commonly used in applications such as UV index monitoring, UV sterilization systems, environmental sensing, and wearable devices that track UV exposure.
This circuit uses an Arduino UNO to control a set of UV-C LEDs via a FemtoBuck LED driver, based on input from two UV light sensors. The UV LEDs are activated by a push button and remain on until the sensors detect a desired UV level, at which point the LEDs are turned off and a green indicator LED is lit.
Open Project in Cirkit Designer
This circuit is designed to measure UV intensity using an ML8511 UV sensor and display the readings on a 16x2 I2C LCD screen. The Arduino UNO microcontroller reads the analog output from the UV sensor, processes the signal, and then outputs the UV intensity data to the LCD. The circuit is powered by a 9V battery, with a resistor in series with the sensor for voltage division or current limiting.
Open Project in Cirkit Designer
This circuit utilizes a Photoresistor (LDR) sensor to measure ambient light levels and display the results on a 16x2 I2C LCD. The Arduino UNO processes the sensor data and updates the LCD to indicate whether the environment is 'Light' or 'Dark' based on the calculated lux value.
Open Project in Cirkit Designer
This circuit consists of an Arduino UNO microcontroller board connected to an LDR (Light Dependent Resistor) sensor module (LM393). The LDR sensor's digital output (D0) is connected to the Arduino's digital pin D4, allowing the Arduino to detect light intensity changes. The sensor is powered by the Arduino's 5V output, and both share a common ground.
Open Project in Cirkit Designer| Pin Number | Name | Description |
|---|---|---|
| 1 | VIN | Power supply (3.3V to 5V) |
| 2 | GND | Ground connection |
| 3 | SCL | I2C clock line |
| 4 | SDA | I2C data line |
| 5 | INT | Interrupt pin (optional use) |
To use the LTR390 with an Arduino UNO, you will need to use the I2C communication protocol. Below is a sample code snippet to get started with reading UV index values from the sensor.
#include <Wire.h>
#include <Adafruit_LTR390.h>
Adafruit_LTR390 uv = Adafruit_LTR390();
void setup() {
Serial.begin(9600);
// Initialize the sensor
if (!uv.begin()) {
Serial.println("Couldn't find LTR390 sensor!");
while (1);
}
Serial.println("Found LTR390 sensor");
}
void loop() {
// Perform a UV reading
uint32_t uv_index = uv.readUVS();
Serial.print("UV Index: ");
Serial.println(uv_index);
delay(1000); // Wait for 1 second before the next reading
}
Q: Can the sensor measure visible light? A: Yes, the LTR390 can measure both UV and ambient light.
Q: What is the range of UV index values the sensor can measure? A: The sensor can measure UV index values from 0 to 11+.
Q: Is the sensor waterproof? A: No, the LTR390 is not waterproof. Protect it from moisture and water exposure.
Q: How do I calibrate the sensor? A: Calibration involves comparing the sensor readings to a known light source or a reference sensor. Adafruit provides a detailed guide on calibration procedures.
For further assistance, consult the Adafruit LTR390 datasheet and the Adafruit support forums.