Ldr Sensor Circuit. As you can see in the ldr circuit diagram it can be a distinguished as two smaller circuits. The circuit of light detector is very simple and easy to build with very few components.
This circuit changes the ac supply into a dc. Which turn led on when light is not falling on ldr and turn led off when light falling on ldr. The resistance of a photoresistor decreases with increasing incident light intensity in other words it exhibits photoconductivity.
By using such characteristic of ldr we can build a ldr darkness sensor circuit which turn on light in darkness and turn off light when there is sufficient light.
A photoresistor can be applied in light sensitive detector circuits and light and dark activated switching circuits. This circuit detects light incident on the ldr and turns on led whenever the intensity of light is greater than a certain level. This sensor also is known as the photoresistor sensor. In this tutorial we ll learn how to make a light sensor circuit using ldr light dependent resistor 555 timer ic and a few other electronics components.
