Dark Light Sensor Circuit Diagram. Ldr circuit diagram dark sensor circuit. This is a light controlled led light circuit light activated switch which fully depends on light.
The following is the pin diagram of the 555 timer ic. In this project we are using an ldr to detect darkness i e. So the voltage at the base of transistor increases when the brightness of light decreases and once it gets past the minimum threshold voltage required at the base of transistor it turns on the led.
This is the basic dark and light sensor which using photoresistor as sensing component.
The diode in the circuit diagram shows to be 1n914. In this project we are using an ldr to detect darkness i e. So the voltage at the base of transistor increases when the brightness of light decreases and once it gets past the minimum threshold voltage required at the base of transistor it turns on the led. We will design the circuit with respect to 555 timer ic.
