# Photosensitive light sensor KY-018

> Photosensitive module KY-018 with photoresistor for measuring light level, compatible with Arduino and other development boards. Integrates a 10k resistor for a voltage divider, providing an analog output signal. Supply voltage 3.3-5VDC, compact PCB mount. Suitable for automation, smart lighting and day-night detection.

- Page: https://sigmanortec.ro/en/photosensitive-light-sensor-ky-018
- Price: 2.81 RON
- Availability: In stock; 1-2 zile
- Reference: 33167 · EAN: 5948289124817
- Category: Mechatronics and IoT > Sensors and Modules > Light and Optical Sensors
- Package (shipping data): 0.002 kg
- Updated: 2026-09-14
- Shop: [Sigmanortec.ro](https://sigmanortec.ro/en/llms.txt)
- Prices: RON, VAT included; prices and stock as of 2026-10-22 03:25 (Europe/Bucharest)

## Description

Photosensitive module with photoresistor for measuring light level, ideal for Arduino projects and other development boards. Integrates 10k resistor for voltage divider, providing stable analog signal for reading on analog input. Operates at 3.3-5VDC, compact PCB mounting, suitable for automation, smart lighting and day/night detection.
Light photoresistor sensor, compatible with Arduino and other development boards.
When connecting a photoresistor to the development boards, their resistance limits the current but without creating a voltage that can be understood by the development board on the analog input. With photoresistors, this is solved by adding a resistor and creating a voltage divider to measure the voltage.
This board solves the problem mentioned above by integrating a 10k resistor that serves this purpose.
Depending on the batch, it is possible that the markings on the PCB are incorrect. Follow the connection diagram in the picture below, completely ignoring the markings on the board.
Specifications:
Supply voltage: 3.3 - 5VDC
Output type: Analogue
Model: KY-018