Circuit Documentation

Summary

This document provides a detailed description of a simple light-sensitive circuit. The circuit uses a BC547 transistor, a Light Dependent Resistor (LDR), a white LED, a resistor, and a 9V battery. The LED lights up when the LDR detects a certain level of light, controlled by the transistor.

Component List

1. BC547 Transistor

   • Pins: Collector, Base, Emitter
   • Description: NPN Bipolar Junction Transistor
   • Purpose in Circuit: Acts as a switch to control the LED based on the LDR input.

2. Photocell (LDR)

   • Pins: pin 0, pin 1
   • Description: Light Dependent Resistor
   • Purpose in Circuit: Changes resistance based on light intensity, influencing the transistor's base current.

3. LED: Two Pin (white)

   • Pins: cathode, anode
   • Description: Light Emitting Diode
   • Purpose in Circuit: Emits light when current flows through it.

4. Resistor

   • Pins: pin1, pin2
   • Description: Fixed Resistor
   • Purpose in Circuit: Limits current to protect the components.
   • Properties:
     • Resistance: 10,000 Ohms (10kΩ)

5. 9V battery

   • Pins: +, -
   • Description: Power Source
   • Purpose in Circuit: Provides the necessary voltage to power the circuit.

Wiring Details

BC547 Transistor

• Collector is connected to the cathode of the LED.
• Base is connected to pin 0 of the Photocell (LDR) and pin1 of the Resistor.
• Emitter is connected to pin 1 of the Photocell (LDR) and the negative terminal of the 9V battery.

Photocell (LDR)

• pin 0 is connected to the Base of the BC547 Transistor and pin1 of the Resistor.
• pin 1 is connected to the Emitter of the BC547 Transistor and the negative terminal of the 9V battery.

LED: Two Pin (white)

• cathode is connected to the Collector of the BC547 Transistor.
• anode is connected to the positive terminal of the 9V battery and pin2 of the Resistor.

Resistor

• pin1 is connected to pin 0 of the Photocell (LDR) and the Base of the BC547 Transistor.
• pin2 is connected to the anode of the LED and the positive terminal of the 9V battery.

9V battery

• + is connected to the anode of the LED and pin2 of the Resistor.
• - is connected to pin 1 of the Photocell (LDR) and the Emitter of the BC547 Transistor.

Code

There is no microcontroller code associated with this circuit.