The GUVA-S12SD is a true UV detector that detects light from 240nm to 370nm which is the UV-B and most of the UV-A spectrum, it also picks up the upper end of UV-C. It uses a UV photodiode, which can detect the 240-370nm range of light. The signal level from the photodiode is very small, in the nano-ampere level, so it comes with an opamp to amplify the signal to a more manageable volt-level.

This sensor is much simpler than Si1145 breakout, it only does one thing and gives an analog voltage output instead of requiring a complicated I2C setup procedure. This makes it better for simple projects. It also has a 'true' UV sensor instead of a calibrated light-sensor. To use, power the sensor and op-amp by connecting V+ to 2.7-5.5VDC and GND to power ground. Then read the analog signal from the OUT pin. The output voltage is: Vo = 4.3 * Diode-Current-in-uA. So if the photocurrent is 1uA (9 mW/cm^2), the output voltage is 4.3V. You can also convert the voltage to UV Index by dividing the output voltage by 0.1V. So if the output voltage is 0.5V, the UV Index is about 5.

Specifications

• Detects UV light in the 240nm – 370nm range
• Analog voltage output proportional to the UV Index of UV light falling on the detector
• 3.3 and 5V compatible

Documents:

• Datasheet