preset level set by the 20K variable resistor. The second circuit is a light sensor that will activate the output LED when the light reaches to a preset level set by the 20K variable resistor.

The sensitivity of the circuit can be further increased by experimenting with the values of 10K resistor and variable resistor.  The circuit can be operated with any voltage from 3V to 30V. The LED current limiting resistor must be increased if operating voltage is higher than 12 volt is used.

Privacy Policy
Copyright 2016 CircuitDiagram.Org. All rights reserved.
The figure below shows two projects of light and dark sensors using LM358 IC. LM358 is a low cost good quality dual operational amplifier IC that is used as a comparator in the circuit.
The first circuit is a dark sensor; that will show visual indication by activating an LED when the darkness reaches to a
Hello Readers, We frequently add new circuit diagrams, so do not forget to come back often. Thank you.
Sponsored Links
Light Dark Sensor Using LM358 IC