Starting Electronics Needs Your Help!
It is that time of the year when we need to pay for web hosting and buy new components and equipment for new tutorials. You can help by making a donation. Contribute to this website by clicking the Donate button. The total will be updated once daily. (You may need to clear your browser cache to see the updates.)

Target Amount: $2000
Amount Raised: $1960

Donations Received

Top Donor: C.C. $100


LDR (Photoresistor)

Created on: 30 July 2012

A LDR (Light Dependent Resistor) or photoresistor is a resistor that will change its resistance, depending on how much light is shining on it. As the light intensity on the LDR increases, so the resistance of the LDR decreases.

Schematic symbols for a LDR or photoresistor are shown below:

Schematic symbols for a LDR or photoresistor

This photo shows what physical LDRs look like.

Light dependent resistors