A light dependent resistor changes its resistance based on the intensity of light hitting its surface. In bright light, resistance drops to 10–20 KΩ on this 12mm LDR Sensor. In darkness, resistance climbs into the megaohm range. That large resistance swing between lit and dark conditions makes the ldr sensor easy to read through a simple voltage divider — one fixed resistor in series, with the midpoint voltage read by any microcontroller ADC pin. The 12mm diameter dome gives a larger photosensitive surface than standard 5mm components, which improves response in low-ambient-light conditions.
The spectral peak sits at 560 nm — the green-yellow portion of the visible spectrum, which closely matches human eye sensitivity. That alignment means the ldr electronics response tracks perceived brightness rather than just raw photon count, making it suitable for applications where the sensor should respond the way a human eye would. The light dependent resistor datasheet parameter of 10–20 KΩ under illumination defines the lower resistance bound for voltage divider design — a 10 KΩ fixed resistor in series gives a mid-range voltage at typical indoor brightness levels, which centres the ADC reading comfortably within the 0–5V range.
The light dependent resistor 2-pin body at 12mm diameter fits standard 12mm PCB footprints and panel-mount holes used in enclosure builds. The 12mm ldr sensor lead length allows direct breadboard insertion for prototyping or trimming for PCB soldering. Compatible with 3.3V to 5V systems, it connects without level shifting to most development boards used in India. StemVolt stocks this component for engineers and students building light-reactive circuits and practical embedded sensing applications.
Related Product:
- Explore the 650nm Mini Laser Dot Diode Module
Features:
- Diameter of 12mm fits standard through-hole PCB footprints without any modification
- Compatible with 3.3V to 5V systems so no level shifting is needed for ESP boards
- Two-pin through-hole body allows direct breadboard or PCB insertion for quick testing
Technical Specifications:
Applications:
- An automatic night lamp uses this to turn on a light when the room gets dark
- A 12mm LDR sensor reads ambient brightness and controls LCD backlight intensity automatically
- A light dependent resistor in a line follower reads surface reflection to steer the robot
Package Includes:
- 1 x 12mm LDR Sensor
Sunil Pancholi –
Great value for money
Yogesh Nama –
On time delivery
Ashish Rathi –
12mm LDR Sensor provides reliable light sensing performance and is ideal for automatic lighting systems, DIY projects, and STEM learning applications.
Preeti Mahawar –
No complaints at all
Kavita Dhankar –
Received this LDR sensor with bubble wrap packing and COD option, sensitivity was excellent and it worked perfectly for my light detection project.