HCSR501 PIR Motion Sensor module for reliable motion detection in electronics projects Overview The HCSR501 is a compact PIR motion sensor module that detects human and animal movement using a Fresnel lens and onboard signal conditioning. It runs from a 5V supply and provides a 3.3V TTL output, with adjustable sensitivity and time delay via onboard potentiometers. The module delivers stable performance while keeping power use low. Key benefits Simple integration: 3.3V TTL output and 5V operation make it easy to connect to common microcontrollers such as Arduino, Raspberry Pi, and PIC. Tunable detection: Onboard potentiometers let you adjust sensitivity and holding time to match different environments, reducing false triggers. Reliable sensing: Fresnel lens plus signal conditioning provides a wide 120 degree field of view and consistent detection out to 7 meters. Low power operation: Typical current draw of 65mA supports battery and lowpower applications without large energy overhead. Compact and practical: PCB module design fits into DIY projects and product prototypes where space is limited. Specifications and features Model: HCSR501 Supply voltage: 5V Output: 3.3V TTL signal suitable for direct input to logiclevel microcontroller pins Adjustable sensitivity and hold time via onboard potentiometers Detection angle: 120 degrees Detection range: up to 7 meters (environment dependent) Typical current consumption: 65mA Optical element: Fresnel lens Onboard signal conditioning circuitry for stable output Typical applications Motionactivated lighting: turn lights on in hallways, closets, or entryways only when movement is detected. Security and alarm systems: trigger alerts or cameras when motion is detected within the sensor field. Smart home and automation: integrate with microcontroller projects to automate scenes, control devices, or record events. DIY electronics and prototyping: quick to add motion detection to custom builds and testing setups. Integration notes The HCSR501 is intended for direct connection to microcontroller input pins using its 3.3V TTL output. Adjust sensitivity and time delay on the module to suit the installation environment. Detection performance may vary with ambient temperature and placement; mounting the lens with a clear view of the monitored area helps maximize range and reliability.