PIR & Motion Sensor
PIR & Motion Sensor
Introduction Noise Equivalent Power (NEP) is a key figure of merit for infrared detectors. It quantifies the minimum detectable signal power. This article explains what NEP means for PIR sensors and how to use it in design. Definition of NEP…
Introduction Thermal camera arrays (e.g., MLX90640, AMG8833) are becoming popular for occupancy sensing. This article compares them with traditional PIR sensors to help you choose the right technology. How Thermal Camera Arrays Work Thermopile arrays consist of multiple thermopile sensors…
Introduction The final stage in a PIR signal chain is a comparator that converts the analog signal to a clean digital output. Adding hysteresis prevents oscillation when the signal hovers near the threshold. Why Hysteresis is Essential Without hysteresis, when…
Introduction The raw output from a pyroelectric sensor is a tiny signal, typically millivolts or less, requiring significant amplification before it can be processed. This guide covers the design of a complete analog front-end. Signal Characteristics Amplitude: 1-50 mV peak-to-peak…
Introduction To properly place a PIR sensor, you need to understand its field of view (FOV) and how it translates to actual coverage area. This article provides the formulas and calculations needed. Basic Parameters Horizontal FOV (θ_h): The angle the…
Introduction The Murata IRA-S200ST01 is a high-performance pyroelectric infrared sensor widely used in security systems, automatic doors, and occupancy detection. This article provides a complete technical analysis of its specifications, characteristics, and integration requirements. Key Specifications Parameter Value Package TO-5…
Introduction PIR sensors have been around for decades, but they continue to evolve. Here are the key trends shaping the future of motion sensing. 1. Ultra-Low Power for Energy Harvesting As IoT devices aim for battery-free operation, PIR sensors are…
Introduction A PIR sensor datasheet contains all the technical information you need to use the sensor correctly. But if you’re new, the jargon can be overwhelming. This guide explains common sections and parameters. Typical Sections of a PIR Sensor Datasheet…
Introduction Home Assistant is a popular open-source home automation platform. Combining it with ESP32 and PIR sensors lets you create powerful automations. This guide walks you through the setup. Hardware Needed ESP32 development board (e.g., NodeMCU-32S) PIR sensor (AM312 or…
Introduction Thermopile sensors are often confused with PIR sensors because both detect infrared. However, they operate on different principles and serve different purposes. This article clarifies the differences. PIR (Passive Infrared) – Motion Detection Principle: Pyroelectric effect – generates charge…