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I am having diffuclt times with this sensor, so I kndliy ask for your help! The sensor is named "SPUVA-CS-C3535-A", datasheet here. The sensor I use (cs3535) has just two pins (+ and -). From my undesrstanding the ouput is a current corresponding on the UV light exposed to this sensor. Max value of the current is difficult to understand from the datasheet that also do not have a typical suggested circuit. It seems that a medium value is 200nA, it seems really low! I have connected (+) of the sensor to 3.3V, (-) of the sensor to A0, and a 220ohm resistor from A0 to Gnd. But readings are always 0. Any help would be really appreciated! Thanks

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The "sensor" is just a photodiode that is sensitive to UV. You use it the same as any photodiode.

The simplest (and crudest) way is to use a very large (eg 1MΩ) pullup resistor to 5V on an ADC pin, then connect the sensor (reverse biased) between the ADC pin and GND.

  • Thanks. I tried your suggestion, I get an high value (about 600) from the analog input, without UV light on the sensor, and it goes down to 100 when it is exposed. Is this normal? I connected 3.3V -- 1mohm -- (+) sensor (-) Gnd. A0 to (+) of sensor. Also the read value is not instantyl changed, instead it "drifts" to a value during several seconds... – Madaeon Feb 26 at 16:08
  • That sounds about right, yes. As light falls on it some small current leaks through it, reducing the voltage across it. – Majenko Feb 26 at 16:28
  • Ok. Thank you very much for your answer. – Madaeon Feb 26 at 17:46

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