Photosensitive Resistor Sensor Module KY-018

Photosensitive Resistor Sensor Module KY-018

Sensors
DET568
Part.No: KY-018
€2.00
In Stock
Immediate Dispatch
KY-018 Photosensitive Resistor Sensor Module – an analog light sensor for Arduino and compatible boards. Detects ambient light intensity and outputs a varying analog voltage. Ideal for automatic lighting, alarm systems, and light-controlled projects.

 

The KY-018 Photosensitive Resistor Sensor Module (MPN: KY-018) is an analog light detection module built around a photoresistor (LDR – Light Dependent Resistor). Its core principle is simple: resistance decreases as light intensity increases, producing a varying analog voltage on its signal pin. This makes it the go-to solution for any project that needs to sense ambient brightness, from automatic night lights to light-triggered alarms.

Κύρια Χαρακτηριστικά / Key Features

  • Analog Light Sensing: The onboard photoresistor changes resistance with light intensity → enables fine-grained brightness measurement via analog input
  • Three Photoresistor Types (by spectral response): UV-sensitive, Infrared-sensitive, and Visible-light-sensitive variants exist in the photoresistor family → choose the right type for your light spectrum
  • Key Parameters – Dark Resistance & Dark Current: At a given voltage with no light, the resistor exhibits high dark resistance and low dark current → ensures predictable baseline readings in the dark
  • Sensitivity: Defined as the ratio of dark resistance to illuminated resistance → higher sensitivity means a larger swing between dark and lit states
  • Compact Module Format: Photoresistor pre-mounted on a small PCB with signal, power, and ground pins → plug-and-play connection, no soldering of the sensor itself required

Pinout & Wiring

PINSymbolDescription
1S (Signal)Analog output – voltage varies with light level
2+Power supply (VCC)
3–Ground (GND)

Wiring note: Connect S to an analog input pin (e.g., A0 on Arduino), + to 5 V, and – to GND. Read the analog value with analogRead(A0); higher values typically indicate less light (higher resistance).

Compatibility

  • Arduino UNO / Nano / Mega: Fully compatible – connect directly to 5 V and any analog input pin.
  • ESP32 / ESP8266: Compatible at 3.3 V; the signal output is suitable for 3.3 V ADC inputs.
  • Raspberry Pi: Requires an ADC (e.g., MCP3008) since Raspberry Pi has no built-in analog input.

Typical Applications

  • Automatic night lights: Turn on LEDs or relays when ambient light drops below a threshold.
  • Light-triggered alarms: Detect sudden darkness or light flashes (e.g., laser tripwire).
  • Smart blinds & curtain controllers: Adjust position based on sunlight intensity.
  • Weather stations & data loggers: Log ambient light levels alongside temperature and humidity.
  • Educational projects: Demonstrate analog sensing, voltage dividers, and ADC concepts with Arduino.

Technical Specifications

ParameterValue
InterfaceAnalog
Sensor TypePhotoresistor (LDR)
Spectral VariantsUV-sensitive / Infrared-sensitive / Visible-light-sensitive
MPNKY-018

FAQ

Q: Does the KY-018 give a digital or analog output?
A: The KY-018 provides an analog output – the signal voltage varies continuously with light intensity, so you need to connect it to an analog input pin (ADC) on your microcontroller.

Q: Can I use the KY-018 with a 3.3 V board like the ESP32?
A: Yes. The module operates over a range that is compatible with 3.3 V systems, making it suitable for ESP32 and similar boards.

Package Contents: 1 × KY-018 Photosensitive Resistor Sensor Module
Category: Arduino Modules
16 other products in the same category:
Product added to wishlist
Product added to compare.