{"product_id":"adafruit-ltr390-uv-light-sensor-stemma-qt-qwiic","title":"Adafruit LTR390 UV Light Sensor - STEMMA QT\/Qwiic","description":"\u003cdiv class=\"product-copy\"\u003e\n \u003cstyle\u003e\n .product-copy{line-height:1.7;color:#1f2937}\n .product-copy \u003e * + *{margin-top:1rem}\n .product-copy h2{margin:1.4em 0 .6em;color:#111827}\n .product-copy h3{margin:1.1em 0 .5em;color:#111827}\n .product-copy p{margin:0 0 1em}\n .product-copy ul,.product-copy ol{margin:0 0 1.2em 1.2em}\n .product-copy li{margin:.35em 0}\n .product-copy table{width:100%;border-collapse:collapse;margin:1.2em 0}\n .product-copy table th,.product-copy table td{border:1px solid #e5e7eb;padding:.7em .8em;text-align:left;vertical-align:top}\n .product-copy table th{background:#f9fafb;width:32%}\n .faq-list{margin:1.2rem 0 1.4rem}\n .faq{border:1px solid #e5e7eb;border-radius:12px;padding:.85rem 1rem;margin:.6rem 0;background:#fafafa}\n .note{background:#f8fafc;border-left:4px solid #2563eb;padding:.85rem 1rem;border-radius:8px}\n \u003c\/style\u003e\n\n \u003ch2\u003eMeasure Real UVA and Ambient Light in One Compact Sensor\u003c\/h2\u003e\n\n \u003cp\u003e\n The \u003cstrong\u003eAdafruit LTR390 UV Light Sensor - STEMMA QT \/ Qwiic\u003c\/strong\u003e is a compact digital breakout that lets your project detect both\n \u003cstrong\u003eUVA light\u003c\/strong\u003e and \u003cstrong\u003eambient light levels\u003c\/strong\u003e from a single board. It’s a great choice for sunlight monitoring,\n UV exposure projects, outdoor sensing, plant-light experiments, and smart devices that react to changing light conditions.\n \u003c\/p\u003e\n\n \u003cp\u003e\n Unlike many basic UV modules, the LTR390 is a \u003cstrong\u003etrue UVA sensor\u003c\/strong\u003e with a dedicated UV-sensitive channel. It also includes internal\n biasing and ADC circuitry, so you can read data directly over \u003cstrong\u003eI2C\u003c\/strong\u003e without needing an analog input pin or extra signal-conditioning hardware.\n \u003c\/p\u003e\n\n \u003cdiv class=\"note\"\u003e\n \u003cstrong\u003eImportant:\u003c\/strong\u003e The sensor does not natively output a ready-made UV Index value on its own. Instead, software libraries can convert\n the raw UV reading into an estimated \u003cstrong\u003eUV Index\u003c\/strong\u003e, while ambient light data can be converted into \u003cstrong\u003elux\u003c\/strong\u003e.\n \u003c\/div\u003e\n\n \u003ch3\u003eWhy you'll love it\u003c\/h3\u003e\n \u003cul\u003e\n \u003cli\u003e\n\u003cstrong\u003eTrue UVA sensing:\u003c\/strong\u003e Better than simple visible-light approximations for UV-aware projects\u003c\/li\u003e\n \u003cli\u003e\n\u003cstrong\u003eAmbient light sensing too:\u003c\/strong\u003e Monitor both UV and brightness from one sensor\u003c\/li\u003e\n \u003cli\u003e\n\u003cstrong\u003eDigital I2C interface:\u003c\/strong\u003e Easy to use with Arduino, Raspberry Pi, Feather, ESP32, and more\u003c\/li\u003e\n \u003cli\u003e\n\u003cstrong\u003eNo analog pin needed:\u003c\/strong\u003e Internal ADC and biasing are already built in\u003c\/li\u003e\n \u003cli\u003e\n\u003cstrong\u003e3V and 5V friendly:\u003c\/strong\u003e Onboard regulator and level shifting simplify wiring\u003c\/li\u003e\n \u003cli\u003e\n\u003cstrong\u003eSTEMMA QT \/ Qwiic ready:\u003c\/strong\u003e Fast solderless hookup for I2C builds\u003c\/li\u003e\n \u003cli\u003e\n\u003cstrong\u003eInterrupt pin available:\u003c\/strong\u003e Useful for threshold alerts or event-driven sensing\u003c\/li\u003e\n \u003c\/ul\u003e\n\n \u003ch3\u003eWhat you can build\u003c\/h3\u003e\n \u003cp\u003e\n This breakout is ideal for UV exposure meters, sunlight trackers, outdoor data loggers, wearable weather projects, greenhouse monitors,\n smart blinds, light-reactive installations, and portable devices that need both UV and ambient light awareness.\n \u003c\/p\u003e\n\n \u003ch3\u003eStarter bundles\u003c\/h3\u003e\n \u003cp\u003e\n Pair it with an \u003ca href=\"\/search?q=arduino\"\u003eArduino-compatible board\u003c\/a\u003e, \u003ca href=\"\/search?q=raspberry+pi\"\u003eRaspberry Pi\u003c\/a\u003e,\n or \u003ca href=\"\/search?q=feather\"\u003eAdafruit Feather\u003c\/a\u003e, plus a \u003ca href=\"\/search?q=STEMMA+QT+cable\"\u003eSTEMMA QT cable\u003c\/a\u003e\n for quick plug-and-play setup.\n \u003c\/p\u003e\n\n \u003ch3\u003eRecommended add-ons\u003c\/h3\u003e\n \u003cp\u003e\n Useful add-ons include OLED displays, battery packs, enclosures, microSD logging boards, and other environmental sensors if you want to build\n a complete weather or sunlight-monitoring station.\n \u003c\/p\u003e\n\n \u003ch3\u003eTechnical specifications\u003c\/h3\u003e\n \u003ctable\u003e\n \u003ctr\u003e\n \u003cth\u003eProduct\u003c\/th\u003e\n \u003ctd\u003eAdafruit LTR390 UV Light Sensor - STEMMA QT \/ Qwiic\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003cth\u003eMain Sensor\u003c\/th\u003e\n \u003ctd\u003eLTR390\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003cth\u003eSensing Modes\u003c\/th\u003e\n \u003ctd\u003eUVA sensing and ambient light sensing\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003cth\u003ePeak UV Response\u003c\/th\u003e\n \u003ctd\u003eApproximately 300nm to 350nm\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003cth\u003eInterface\u003c\/th\u003e\n \u003ctd\u003eI2C\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003cth\u003eSignal Conditioning\u003c\/th\u003e\n \u003ctd\u003eInternal biasing and ADC onboard\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003cth\u003ePower Input\u003c\/th\u003e\n \u003ctd\u003e3V to 5V DC\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003cth\u003eLogic Compatibility\u003c\/th\u003e\n \u003ctd\u003e3V to 5V logic via onboard level shifting\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003cth\u003eConnector Type\u003c\/th\u003e\n \u003ctd\u003eDual STEMMA QT \/ Qwiic-compatible JST SH connectors\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003cth\u003eExtra Pin\u003c\/th\u003e\n \u003ctd\u003eINT interrupt output\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003c\/table\u003e\n\n \u003ch3\u003ePinout \u0026amp; usage notes\u003c\/h3\u003e\n \u003cp\u003e\n The breakout uses a simple \u003cstrong\u003eI2C interface\u003c\/strong\u003e with power, ground, \u003cstrong\u003eSDA\u003c\/strong\u003e, and \u003cstrong\u003eSCL\u003c\/strong\u003e,\n plus an \u003cstrong\u003eINT\u003c\/strong\u003e pin for interrupt-based applications. Because it is fully digital, it works especially well with modern boards\n that have limited or no analog inputs.\n \u003c\/p\u003e\n\n \u003cp\u003e\n In software, you can read raw UV and ambient light values directly, then use Adafruit’s library routines to derive\n \u003cstrong\u003eUV Index\u003c\/strong\u003e and \u003cstrong\u003elux\u003c\/strong\u003e when needed.\n \u003c\/p\u003e\n\n \u003ch3\u003eWhat’s in the box\u003c\/h3\u003e\n \u003cp\u003e\n 1 × Adafruit LTR390 UV Light Sensor breakout\n \u003c\/p\u003e\n \u003cp\u003e\n \u003cstrong\u003eNote:\u003c\/strong\u003e STEMMA QT cable is not included.\n \u003c\/p\u003e\n\n \u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n \u003cdiv class=\"faq-list\"\u003e\n \u003cdiv class=\"faq\"\u003e\n \u003cstrong\u003eDoes this measure real UV light?\u003c\/strong\u003e\n Yes. The LTR390 has a dedicated UVA sensing channel instead of only estimating UV from visible light.\n \u003c\/div\u003e\n \u003cdiv class=\"faq\"\u003e\n \u003cstrong\u003eDoes it output UV Index directly?\u003c\/strong\u003e\n Not by itself. You read the raw UV data, then software can derive a UV Index estimate.\n \u003c\/div\u003e\n \u003cdiv class=\"faq\"\u003e\n \u003cstrong\u003eCan I use it with Arduino or Raspberry Pi?\u003c\/strong\u003e\n Yes. It uses I2C and is designed for common maker platforms.\n \u003c\/div\u003e\n \u003cdiv class=\"faq\"\u003e\n \u003cstrong\u003eDo I need an analog pin?\u003c\/strong\u003e\n No. The sensor is fully digital and includes the ADC internally.\n \u003c\/div\u003e\n \u003cdiv class=\"faq\"\u003e\n \u003cstrong\u003eIs the QT cable included?\u003c\/strong\u003e\n No. The board has STEMMA QT \/ Qwiic connectors, but the cable is sold separately.\n \u003c\/div\u003e\n \u003c\/div\u003e\n\u003c\/div\u003e","brand":"Adafruit","offers":[{"title":"Default Title","offer_id":52445329785121,"sku":"4831","price":416.0,"currency_code":"PHP","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0777\/1491\/5617\/files\/4831-07_52675ef9-4b88-4a43-b90a-a4b0aff900cd.jpg?v=1773455443","url":"https:\/\/circuit.rocks\/products\/adafruit-ltr390-uv-light-sensor-stemma-qt-qwiic","provider":"circuitrocks","version":"1.0","type":"link"}