SparkFun Mini Spectral UV Sensor - AS7331 (Qwiic)

The SparkFun Qwiic Mini Spectral UV Sensor, featuring the AS7331 UV sensor from ams OSRAM®, measures UV radiation across three channels: UVA (320-400nm), UVB (280-320nm), and UVC (200-280nm) with high sensitivity and accuracy. This compact breakout board, measuring just 1.27cm by 2.54cm, offers three operating modes: Single Measurement (CMD), Continuous Measurement (CONT), Synchronized Start (SYNS), and Synchronized Start & End (SYND), with an automatic power-down sequence to minimize current consumption.

With I²C communication, this mini breakout routes the I²C bus pins (3.3V, GND, SDA, and SCL) to a Qwiic connector for solderless assembly. It also provides a 2.54mm-spaced through-hole header on the bottom for those who prefer soldered connections. This header includes the sensor's Interrupt and Sync pins. The AS7331 supports four I²C addresses (default: 0x74), adjustable via the A1 and A0 solder jumpers on the back of the board.

An Arduino library is available to simplify configuring the AS7331 and obtaining UV radiation data. This library can be downloaded through the Arduino Library Manager by searching for 'SparkFun AS7331' or directly from the GitHub repository in the Documents section.

Features:

• Operating Voltage: 2.7V-3.6V
• Current Consumption:
  • Active Measurement: 1.42mA (Typ.)
  • Standby Mode: 970µA
  • Power Down Mode: 1µA
• Three UV Channels: UVA, UVB, & UVC
  • Each with dedicated photodiode
• Four Operating Modes:
  • Single Measurement
  • Continuous Measurement
  • Synchronized Start Measurement
  • Synchronized Start/Stop Measurement
• High Dynamic Range: Up to 3.43E+10 (resolution multiplied by gain range)
• 2x Qwiic Connectors
• Four Adjustable I²C Addresses
  • Set through A0 & A1 pins
  • 0x74 (Default), 0x75, 0x76, & 0x77
• Qwiic Mini Footprint: 2.54cm x 1.27cm

Documents:

• Schematic
• Eagle Files
• Board Dimensions
• Hookup Guide
• Datasheet (AS7731)
• Qwiic Info Page
• SparkFun AS7331 Arduino Library
• GitHub Hardware Repo

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