Sitron Labs Texas Instruments OPT3001 Arduino Library

Arduino library for interfacing with the Texas Instruments OPT3001 ambient light sensor.

Description

The OPT3001 is an ambient light sensor that measures illuminance in lux with a wide dynamic range from 0.01 lux to 83,000 lux. The sensor features automatic full-scale range selection, allowing it to automatically optimize the measurement range for current light conditions. This library provides a simple interface to read illuminance measurements via I2C.

Installation

Arduino IDE

Install via the Arduino Library Manager by searching for "Sitron Labs OPT3001".

Alternatively, install manually:

Download or clone this repository
Place it in your Arduino libraries folder
Restart the Arduino IDE

PlatformIO

Install via the PlatformIO Library Manager by searching for "Sitron Labs OPT3001".

Alternatively, add the library manually to your platformio.ini file:

lib_deps = 
    https://github.com/sitronlabs/SitronLabs_TexasInstruments_OPT3001_Arduino_Library.git

Hardware Connections

Connect the OPT3001 to your Arduino using I2C:

VCC → 3.3V (check your board's specifications)
GND → GND
SDA → SDA (I2C Data)
SCL → SCL (I2C Clock)
ADDR → GND or VCC (I2C address selection)
INT → NC (unused by this library)

The I2C address is determined by the ADDR pin:

ADDR = GND: 0x44
ADDR = VCC: 0x45
ADDR = floating: 0x46 or 0x47 (depends on package)

Usage

Continuous Conversion Mode

#include <Wire.h>
#include <opt3001.h>

// Create sensor object
opt3001 sensor;

// I2C address (0x44, 0x45, 0x46, or 0x47)
const uint8_t I2C_ADDRESS = 0x44;

void setup() {
  Serial.begin(9600);
  
  // Initialize I2C
  Wire.begin();
  
  // Setup the OPT3001 (I2C library, I2C address)
  if (sensor.setup(Wire, I2C_ADDRESS) != 0) {
    Serial.println("Failed to setup OPT3001");
    return;
  }
  
  // Detect the sensor
  if (sensor.detect() != 0) {
    Serial.println("OPT3001 not detected");
    return;
  }
  
  // Configure conversion time (100ms or 800ms)
  sensor.config_set(OPT3001_CONVERSION_TIME_800MS);
  
  // Enable continuous conversion mode
  sensor.conversion_continuous_enable();
  
  Serial.println("OPT3001 initialized");
}

void loop() {
  float lux;
  
  // Read illuminance in lux
  if (sensor.lux_read(&lux) == 0) {
    Serial.print("Illuminance: ");
    Serial.print(lux);
    Serial.println(" lux");
  } else {
    Serial.println("Failed to read illuminance");
  }
  
  delay(1000);
}

Single-Shot Conversion Mode

#include <Wire.h>
#include <opt3001.h>

opt3001 sensor;
const uint8_t I2C_ADDRESS = 0x44;

void setup() {
  Serial.begin(9600);
  Wire.begin();
  
  sensor.setup(Wire, I2C_ADDRESS);
  sensor.detect();
  sensor.config_set(OPT3001_CONVERSION_TIME_100MS);
}

void loop() {
  float lux;
  
  // Trigger single-shot conversion
  sensor.conversion_singleshot_trigger();
  
  // Wait for conversion to complete (100ms in this example)
  delay(150);
  
  // Read the result
  if (sensor.lux_read(&lux) == 0) {
    Serial.print("Illuminance: ");
    Serial.print(lux);
    Serial.println(" lux");
  }
  
  // Sensor automatically enters shutdown mode after conversion
  delay(1000);
}

API Reference

setup(TwoWire &i2c_library, uint8_t i2c_address)

Initializes the OPT3001 sensor.

i2c_library: I2C library instance to use (typically Wire)
i2c_address: I2C address (0x44, 0x45, 0x46, or 0x47)

Returns 0 on success, or -EINVAL if the I2C address format is invalid.

detect(void)

Detects and verifies the presence of an OPT3001 sensor by reading the manufacturer ID and device ID.

Returns 0 if a valid OPT3001 device is detected, or a negative error code otherwise.