Last Updated on March 16, 2024
Simple Light Fence circuit and this circuit can be used for security purpose, by implementing light fence at the entrance gate or entry door we can get notified before the person knock the door. Use white LED biased with 220Ω 3Volt battery for light source.
Components List
| S.No | Name | Quantity |
| 1. | IC 4069 | 1 |
| 2. | LDR medium size | 1 |
| 3. | Relay 9Volt | 1 |
| 4. | Light source (white LED) | as required |
| 5. | Transistor 2N4401 | 1 |
| 6. | Resistor 100KΩ Resistor 10KΩ Capacitor 1 uF/20V Capacitor 100nF Diode 1N4004 |
1 2 1 1 1 |