The repeatable mode is the default and is suitable for most applications (e.g., lights that stay on while someone is in the room). The non‑repeatable mode is useful for triggering a single event per motion.
The is a reliable, low-power motion detection module ideal for hobbyist and industrial prototypes. This article has provided a complete datasheet covering electrical specs, pinouts, potentiometer adjustments, trigger modes, and real-world wiring examples.
Ground connection (Connect to the system common ground). Onboard Adjustments (Potentiometers) hw-416-b pir sensor datasheet
The HW-416-B usually has three pins, often exposed by removing the plastic Fresnel lens dome. OUT (Output): Digital output signal (High/Low). GND (Ground): Ground reference. 4. Key Components & Working Principle
The actual infrared detection is done by a pyroelectric sensor that responds to changes in infrared radiation. Because humans emit infrared at a wavelength of about 10 µm, the sensor is naturally sensitive to human movement. The white dome on top of the module is a . It divides the detection area into multiple zones and focuses the infrared energy onto the sensor, greatly increasing the detection range and angle. Without the Fresnel lens, the sensor would only “see” a narrow, short‑range window. The repeatable mode is the default and is
She imagined the makers: someone soldering tiny resistors, testing detection angles, verifying hold times. The datasheet’s diagrams sketched the connector: Vcc, GND, OUT. A recommended application diagram suggested powering the HW-416-B from a microcontroller’s 3.3V rail and reading the OUT pin through a pull-down resistor. There were cautions too—don’t stare into the Fresnel lens with a laser, avoid prolonged exposure to humidity, and allow thirty seconds of stabilization when powering up; the sensor needed a moment of calm to learn the background temperature before it could tell friend from phantom.
| Pin Name | Function | Description | | :--- | :--- | :--- | | | Power Input | Connect to +5V DC (or 4.5V–20V). Do not exceed 20V. | | GND | Ground | Common ground with the microcontroller or load circuit. | | OUT | Digital Output | Goes HIGH (3.3V) when motion is detected. Falls LOW after lock-down time. | This article has provided a complete datasheet covering
Arduino (through a 220Ω resistor) to act as a visual alarm indicator. 6. Arduino Example Code
Most HW-416-B boards include three solder pads or header pins with a jumper labeled and L .
Because the sensor relies on heat signatures, avoid placing it near air conditioners, heating vents, incandescent light bulbs, or direct sunlight. Rapidly changing ambient air currents can cause false positive triggers.
Approximately 32mm x 24mm (Standard compact footprint) 3. Pinout and Hardware Overview
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