Flora UV Index Sensor - Si1145 Light Sensor

Your wearable can now keep you from getting sunburnt, with the Flora digital UV index sensor. We took our popular SI1145 UV index sensor and cut out everything you don't need for using with a Flora. It's small, round, and connects to the I2C bus pads.

Vin
Input to the onboard regulator; Adafruit says power with 3-5VDC and notes reverse-polarity protection.
Type · powerVoltage · 3-5VDC input
GND
Signal and power ground; connect to microcontroller ground.
Type · groundVoltage · 0V
3Vo
3.3V output from the onboard regulator; Adafruit says up to 100mA can be drawn.
Type · powerVoltage · 3.3V output, up to 100mA
INT
Interrupt output from the SI1145 with a 10K pullup to 3.3V; indicates when conversions are done.
Type · signalVoltage · pulled up to 3.3V
LED
Open-collector IR LED drive pin for proximity use; Adafruit says connect IR LED cathode to this pin and anode to 3-5VDC, with sink spikes up to 300mA.
Type · signalVoltage · open collector, LED anode to 3-5VDC

Start wiring

I2C · 3-5VDC input · 0V

Confirm the data interface matches your host board.

Module pins: Vin, 3Vo, GND, INT, LED, SCL, SDA. Schematik maps them to your board in the app.

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