Looking for Ltr390 Sensor? Adafruit LTR390 UV Light Sensor – STEMMA QT/Qwiic is available at Zbotic with fast shipping across India.
The LTR390 is one of the few low-cost UV sensors available, and it’s a pretty nice one! With both ambient light and UVA sensing with a peak spectral response between 300 and 350nm. You can use it for measuring how much sun you can get before needing to covering up.
Unlike the Si1145, this sensor will not give you UV Index readings. However, the Si1145 does UV Index approximations based on a light level, not true UV sensing. The LTR-390, in contrast, does have a real light sensor in the UV spectrum. It’s also got a much much simpler I2C interface so you can run it on the Arduino or Python microcontrollers/microcomputers with ease. Unlike the GUVA analog sensor, the biasing and ADC is all internal so you don’t need an ADC.
To make using it as easy as possible, we’ve put the LTR390 on a breakout PCB in our Stemma QT form factor with a sprinkle of support circuitry to give you options when testing. You can either use a breadboard or the SparkFun qwiic compatible STEMMA QT connectors, and compatibility with 5V voltage levels as commonly found on Arduinos, as well as 3.3V logic used by many other boards like the Raspberry Pi or our Feathers.
Package Includes:
1 x Adafruit LTR390 UV Light Sensor – STEMMA QT/Qwiic
Datasheet:-
https://cdn-learn.adafruit.com/downloads/pdf/adafruit-ltr390-uv-sensor.pdf
Adafruit LTR390 UV Light Sensor – STEMMA QT/Qwiic Overview
The Adafruit LTR390 UV Light Sensor – STEMMA QT/Qwiic is a compact I2C breakout featuring the LTR390 chip for true UVA (300–350 nm) and ambient light (500–600 nm) measurements. Ideal for DIY weather stations, wearable UV monitors, and plant-growth projects, this sensor provides accurate irradiance readings without complex calibration.
Key Features of Adafruit LTR390 UV Light Sensor – STEMMA QT/Qwiic
- Dual-band sensing: measures UVA (300–350 nm) and ambient light (500–600 nm)
- STEMMA QT/Qwiic plug-and-play I2C interface at address 0x53
- Wide supply range: 3 V to 5 V DC, with onboard level shifting
- Compact PCB breakout with easy mounting holes
- Arduino and CircuitPython libraries with sample code
- Genuine Adafruit hardware, fast shipping from Zbotic across India
Applications and Use Cases
- Wearable UV exposure trackers for skin safety
- Environmental monitoring in weather stations
- Plant-growth chambers to optimize light conditions
- Solar panel efficiency testing by measuring irradiance
- STEM education projects in light and photobiology
How to Use Adafruit LTR390 UV Light Sensor – STEMMA QT/Qwiic
Simply connect the sensor to your microcontroller via a STEMMA QT or Qwiic cable (SDA to SDA, SCL to SCL, VIN to 3–5 V, GND to ground). Install the Adafruit_LTR390 library in Arduino IDE or CircuitPython runtime, initialize the sensor at I2C address 0x53, then read UVA and ambient light values using provided example sketches.
Why Buy from Zbotic?
- Genuine Products: All items sourced from authorized distributors
- Fast Shipping: Orders ship within 24 hours with tracking (non backordered products)
- Free Shipping: Free delivery on qualifying orders
- COD Available: Cash on Delivery, UPI, cards, net banking
- Technical Support: Expert help for setup and troubleshooting
- Easy Returns: Hassle-free replacement for defective products
Frequently Asked Questions
How do I wire the LTR390 sensor to an Arduino?
Use a STEMMA QT or Qwiic cable to connect VIN to 3–5 V, GND to ground, SDA to SDA (A4 on Uno), and SCL to SCL (A5 on Uno). No extra resistors are needed due to onboard level shifting.
Does this sensor output UV Index directly?
No. The LTR390 provides raw UVA irradiance data between 300 nm and 350 nm. You can calibrate those readings against standard UV Index scales in software if required.
Which libraries support the LTR390 on Raspberry Pi?
For Python on Raspberry Pi, use the Adafruit CircuitPython LTR390 library. Install via pip and import adafruit_ltr390 to access both UVA and ambient light measurements over I2C.
Technical Specifications
| Brand | Adafruit |
|---|---|
| Model | LTR390 |
| SKU | AI1750 |
| Weight | 0.008 kg |
| Availability | Out of Stock |
Applications & Use Cases
The Adafruit LTR390 UV Light Sensor – STEMMA QT/Qwiic is a versatile light/color sensor used across a wide range of applications including electronics projects, DIY builds, prototyping, and educational experiments.
Common use cases:
- Integrating into a custom electronics project
- Learning and experimenting with circuits
- Replacing or upgrading components in existing setups
This product is ideal for electronics enthusiasts, engineers, and students.
Technical Tip: Always verify voltage and current requirements before connecting to your circuit. Check datasheets for detailed specifications and pin configurations.
Shipping & Delivery
- Free shipping on orders above ₹999 across India
- Dispatched within 1-3 business days
- Expected delivery: 3-7 business days depending on location
- Secure packaging to ensure safe transit of electronic components
- Genuine Adafruit product sourced from authorized channels
Eshan Parekh (verified owner) –
This Adafruit LTR390 UV Light Sensor – works great with Arduino. Easy to wire up and code.
Chirag Das –
Good Adafruit LTR390 UV Light Sensor –. Works as described. Calibration needed some patience but results are good.
Devansh Nayak (verified owner) –
Decent Adafruit LTR390 UV Light Sensor – for the price. Requires proper wiring but works well once set up.
Vijay Batra (verified owner) –
Good Adafruit LTR390 UV Light Sensor –. Works as described. Calibration needed some patience but results are good.
Lakshya Shetty (verified owner) –
Outstanding accuracy from this Adafruit LTR390 UV Light Sensor –. Compared with a professional instrument, readings match closely.
Shruti Bose –
This Adafruit LTR390 UV Light Sensor – is a must-have for sensor projects. Plug and play with Arduino.
Hitesh Chopra (verified owner) –
Excellent sensitivity and range on this Adafruit LTR390 UV Light Sensor –. Works better than I expected.
Raghav Deshpande (verified owner) –
Good quality Adafruit LTR390 UV Light Sensor –. Some variation in readings but within acceptable range.
Sameer Saxena (verified owner) –
This Adafruit LTR390 UV Light Sensor – is excellent for the price. My data logging project is working perfectly now.
Mukesh Vohra (verified owner) –
Love this Adafruit LTR390 UV Light Sensor –. Response time is fast and readings are stable.