How do we detect light with LDR?
The project aims to learn the operation of a photo-resistor in a circuit with two transistors.
This circuit with two transistors (BC337) activates the LED1 indicator when the light falls on LDR1 (Light Detecting Resistance). The POT1 potentiometer is adjusted for the required sensitivity. The supply voltage is 3V.
List of required components:
1 x Breadboard test board + connecting wires
1 x R1 = 10k
1 x R2 = 10k
1 x R3 = 470 Ohms
1 x R4 = 47 Ohms
1 x POT = 100k
1 x D1 = 1N4148
1 x T1 = BC337
1 x T2 = BC337
1 x Photoresistor (LDR1)
1 x LED
For a better understanding of the circuit's functionality and to make this assembly on the breadboard we will need the electronic diagram presented below:
Also, for this application, the following video materials are available in which similar functionalities are presented: