The WWZMDiB 5-pack AM312 Mini PIR Motion Sensor Module, also known as HC-SR312, is designed for Arduino and other microcontroller projects. Each module integrates a passive infrared sensor with a compact footprint of approximately 10mm x 8mm, making it suitable for space-constrained applications such as automatic lighting, security alarms, and human presence detection. The sensor operates on a DC voltage range of 2.7V to 12V, with a typical quiescent current of less than 50μA, ensuring energy efficiency during standby. Detection range reaches up to 3 meters with a 100-degree cone angle, offering reliable triggering for indoor proximity sensing. The module features a single digital output pin that goes high (3.3V logic level) when motion is detected, and remains low otherwise. The output pulse duration is adjustable via an onboard potentiometer, allowing users to fine‑tune the hold time from approximately 0.5 seconds to 200 seconds. The build quality is consistent with standard mini PIR modules: a black plastic lens covers the pyroelectric element, and the PCB is mounted with a small number of passive components for signal conditioning. The solder joints are clean, and the pin header spacing follows the 2.54mm standard, compatible with breadboards and prototyping boards. These modules are intended for low‑power, always‑on applications where compact size and low cost are priorities. They are not suited for outdoor use or high‑temperature environments without additional enclosures. The HC‑SR312 variant shares the same pinout and functionality as the popular AM312, which is widely used in DIY electronics. Each unit in the pack is individually tested for functionality before packaging. The overall construction focuses on affordability and simplicity, making these sensors an accessible choice for hobbyists and educators exploring motion detection projects. The modules do not include an onboard voltage regulator, so input voltage should be kept within the specified range to avoid damage. When used with Arduino, the output can be read as a digital signal, and multiple modules can be integrated into a single project. The compact size also enables embedding into battery‑powered devices, as the low standby current minimizes drain. While not featuring advanced features like adjustable sensitivity or noise immunity, the module provides reliable binary motion detection for basic interactive systems. The 5‑pack quantity offers good value for prototyping and teaching multiple students or building redundant sensor networks. Each module weighs approximately 2 grams, and the overall package dimensions are small enough for bulk storage. The lens is slightly domed to improve field of view. The response time to motion is under 1 second in typical conditions. For best results, avoid placing the sensor near heat sources or direct air currents.

This product delivers essential motion‑sensing functionality at a very affordable price point, suitable for learning, experimenting, and simple automation tasks.