tecno4

A photoresistor (also known as photocell) is a Light Dependent Resistor (LDR). As the name suggests, these components act just like a resistor, changing their resistance in response to how much light is falling on it. Usually, photoresistors have a very high resistance in near darkness and very low resistance in bright light.
This component is used to manage electronic or electric devices to answer light conditions enabling or disabling functions.

To use, for example, a weather station, it is important to know the brightness. With a Raspberry Pi light sensor (photoresistor/brightness sensor), it is very easy to determine a value, which can say, for example, if it is day, twilight or night.

In turn, projects could be implemented to control the (exterior) lights, which turn on automatically after a certain level of darkness. In this tutorial, we connect such a brightness sensor and read the light values accordingly, so that we can respond.

In this tutorial, I go through the steps of setting up a Raspberry Pi ADC (Analog to digital converter). As you may already know the Pi doesn’t have any GPIO pins that are analog. This lack of analog pins makes connecting analog sensors a little more complex.

There are several solutions to the lack of Analog pins like the one I did in the Raspberry Pi LDR tutorial which involved using a capacitor to measure the resistance of the LDR (Light Dependent Resistor). A better solution to this would be to use what is known as an analog digital converter (MCP3008). This chip involves a little bit of setting up which I will go into below.