LDR – Light Dependent Resistor with Relay Circuit Diagram

LDR – Light Dependent Resistor with Relay Circuit Diagram

LDR Circuit Diagram

The circuit of LDR is an electronic circuit built with  Light Dependent Resistor, relay, Darlington pair, diode, & resistors shown in the below circuit diagram. A voltage supply is given to the load. The required DC voltage of the Light Dependent Resistor circuit is supplied from a bridge rectifier circuit or a battery. This circuit changes the AC supply into a DC. The bridge rectifier circuit uses a step-down transformer to step-down the voltage from 230v into 12v.

LDR circuit diagram

Light Dependent Resistor Circuit Diagram

LDR Circuit Operation:

  • The diodes are connected in the form of a bridge used to alter the AC voltage into DC.
  • The voltage regulator is used to change the 12v DC-6v DC, and then, this DC voltage is supplied to the entire circuit.
  • A 230v AC supply for both the bridge rectifier and the load is to be kept continuously for continuous operation of the light sensor circuit.


LDR circuit diagram 230v
LDR circuit diagram with relay
LDR sensor circuit
LDR darkness sensor circuit pdf
LDR circuit diagram with led
LDR darkness sensor circuit diagram
simple LDR circuit without transistor
how to make LDR circuit

Leave a Comment