How To Make LDR Darkness Sensor Circuit Simple.

LDR Darkness Sensor

LDR Darkness Sensor
LDR Darkness Sensor

In This Video, We Will See How We Can Build A Dark Sensor Using The Ldr Sensor. This Sensor Detects The Light Falling On It And Turns On The Light In The Dark And The Light Turns Off When There Is Enough Lighting.

Parts Required:

Battery 9V Holder
Battery 9V
Green Led
1KΩ Resistance
56KΩ Resistance
2N2222 Transistor
Light Dependent Resistor (LDR)

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How It Works:

LDRStands For The Light-Dependent Resistor, As The Name Suggests It Is A Type Of Resistor Whose Resistance Depends On The Amount Of Light Falling On It.
LDRIs Made Up Of A High Resistance Semiconductor. In Dark, Its Resistance Is High As Several Megaohms, And In Light Its Down To Few Ohms.
So When Sufficient Light Falling On LDR The Resistance Of LDR Is Very Low, As A Result, All Current Is Flowing From Resistor 56KΩ, So LED Is Not Glowing,
When There Is Dark And No Light Is Falling On LDR, So The LDR Resistance Became Very High So Current Will Flow To The Base Of Transistor 2N2222, So Transistor Became To Turn On An LED Glow.

The Build:


LDR Darkness Sensor
LDR Darkness Sensor Schematic


LDR Darkness Sensor
LDR Darkness Sensor Breadboard

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