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

1 Answer 1


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, 2020 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, 2020 at 16:28
  • Ok. Thank you very much for your answer.
    – Madaeon
    Feb 26, 2020 at 17:46

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.