{"product_id":"light-dependent-resistor-ldr-sensor-module","title":"Light Dependent Resistor (LDR) Sensor Module","description":"\u003cdiv class=\"markdown markdown-main-panel tutor-markdown-rendering enable-luminous-fast-follows enable-updated-hr-color\" id=\"model-response-message-contentr_c7fbc8d1bd44e081\" dir=\"ltr\"\u003e\n\u003cp\u003eThis is a standard \u003cstrong\u003eLight Dependent Resistor (LDR) Sensor Module\u003c\/strong\u003e, widely used for light detection and automated switching applications. Based on the components visible in the image, specifically the 3-pin header and the 8-pin IC, here is the technical breakdown.\u003c\/p\u003e\n\u003ch3\u003eCore Components \u0026amp; Operation\u003c\/h3\u003e\n\u003cp\u003eThe board functions by converting the analog resistance changes of the photoresistor into a clean, readable digital signal.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003ePhotoresistor (LDR): The component extending at the bottom. Its resistance decreases as the ambient light intensity increases.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eLM393 Comparator: The black 8-pin surface-mount IC. It compares the varying voltage from the LDR against a fixed reference voltage.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003ePotentiometer: The blue trimpot with the crosshead. This acts as a voltage divider to set the reference voltage for the LM393, allowing you to manually calibrate the exact light threshold at which the sensor triggers.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eStatus LEDs: Typically, these modules feature two LEDs—one to indicate power and another to indicate when the digital output pin is triggered.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003eOperating Voltage: 3.3V to 5V DC.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eOutput Type: Digital Output (DO). It provides a clean HIGH (1) or LOW (0) logic signal.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eLogic State: By default on most of these specific modules, the DO pin outputs HIGH in dark conditions and switches to LOW when the light intensity exceeds your set threshold.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eCurrent Consumption: Typically around 15mA.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eComparator IC: LM393 (Wide supply voltage range, low power consumption).\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eDimensions: Approximately 3.2cm x 1.4cm.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eInterfacing \u0026amp; Prototyping\u003c\/h3\u003e\n\u003cp\u003eThe 3-pin header makes it straightforward to interface with microcontrollers:\u003c\/p\u003e\n\u003col start=\"1\"\u003e\n\u003cli\u003e\n\u003cp\u003eVCC: Connects to your power supply. Pro-tip: If you are interfacing this with 3.3V logic boards (like an ESP32 or STM32), power the module with 3.3V rather than 5V. The LM393 outputs a voltage equal to its supply voltage, so powering it with 3.3V ensures you don't fry your 3.3V-tolerant GPIO pins.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eGND: Connects to common ground.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eDO (Digital Out): Connects to any digital input pin. You can poll this pin in your main loop or, for more efficient code, attach a hardware interrupt to trigger an action exactly when the light state changes.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003c\/div\u003e","brand":"scientifickart","offers":[{"title":"Default Title","offer_id":51355941208370,"sku":"OM-31028","price":59.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0951\/6561\/2338\/files\/ChatGPTImageJun23_2026_06_03_38PM.png?v=1782218073","url":"https:\/\/scientifickart.com\/products\/light-dependent-resistor-ldr-sensor-module","provider":"scientifickart","version":"1.0","type":"link"}