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Adafruit LTR390 UV Light Sensor - STEMMA QT / Qwiic

Adafruit  |  SKU: ADA4831
$9.80 AUD
$8.91 exc GST

Delivery and Shipping

Delivery Options

We offer several delivery choices to fit your needs:

  • FREE Delivery: $0. Enjoy Free AusPost Parcel Standard Delivery on orders over $100 in value. Exclusions may apply.
  • AusPost Untracked Letter: $3. Delivery in 3-8 business days (untracked). No refunds or replacements without proof of receiving the order.
  • AusPost Parcel Standard: $9. Tracked delivery in 2-6 business days.
  • AusPost Parcel Express: $13. Express tracked delivery in 1-3 business days.
  • Pickup: $0. Email us to arrange a pickup from our location in Huntingdale 3166 in Melbourne at support@zaitronics.com.au. More details can be found in our contact page.

Additional Information

  • Non-metro addresses in WA, NT, SA & TAS may require extra time.
  • Certain batteries (like LiPo) cannot be shipped by air, affecting Express Post availability.
  • We recommend selecting tracked options for valuable items. Untracked orders will not receive tracking numbers or refunds without proof of delivery.
  • Note: Wherever possible, we will combine orders to save on shipping and reduce packaging waste.
  • Note: Orders containing backordered item will delay delivery until all items are available

Warranty & Refund Policy

Warranty & Refund Policy

  • Standard Warranty: 12 months for all products. Low-cost hobby parts have a 90-day warranty unless safe handling is shown.
  • Exceptions: Kits and interfaceable electronics may not be covered if damaged due to misuse.
  • Returns: Contact support via your order confirmation email within 14 days of purchase. Items must be unopened and in original packaging. Proof of purchase is required.
  • Defective/Damaged Items: Notify us within 30 days for a free refund or replacement. Exclusions apply.
  • Return Shipping Costs: Paid by the customer unless the item is defective. Shipping costs are non-refundable.

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 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. QT Cable is not included, but we have a variety in the shop for quick plug-and-play support.

Technical Details

Revision History:

  • As of October 2022 – we've updated this PCB with Adafruit Pinguin to make a lovely and legible silkscreen - you may get the new PCB or the older version with vector fonts - both are identical other than the fancy silkscreen. Additionally, this sensor breakout may come with black or tan STEMMA QT connectors. They work the same!
    RoHS 2 2011 65 EU Compliant
    RoHS 2 2015 863 EU Compliant