Light Dependent Resistor is a special type of resistor used for the detection of light. As it is a type of resistor hence it doesn’t have any polarity and can be connected in any direction. LDR provides high resistance of several Mega Ohm in the absence of light but as the light starts striking on its surface the resistance offered by the LDR gradually decreases to a few Ohm. It is widely used in smart street lights, automatic headlight dimmers, automatic rearview mirrors, etc.
LDR module consists of a potentiometer, a comparator-LM393 and LDR. The output of the module goes high in the presence of light and goes low in the absence of light. The sensitivity of the module can be adjusted using a potentiometer.
|Max Voltage||150 volts|
|Max Power||100 mW|
|Light resistance(10 lux)||5-10 k ohm|
|Dark Resistance||>100 k ohm|
|Operating Temperature||-30° to 70° C|
|Number of Pins||2|