Light Dependent Resistor

Datasheet

An LDR is a resistor that varies resistance with the amount of light shining on it. The GL5537 changes resistance from 2000 kOhms in darkness to around 20 Ohms when lots of light shines on it.

Connect as follows:

Note: any Analog pin will do.

You can then easily read the analog value. Because of the way the sensor is wired, the value you'll get will be near 0.5 in darkness, and 1 when there is a lot of light.

var light = analogRead(A1);
console.log(light);

Using

DIY Smart Meter Pico Light Sensor

Buying

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