If you bought a bundle of "HW-416B" PIR sensors from Amazon, AliExpress, or a starter kit, you probably noticed something frustrating:
The is a compact Passive Infrared (PIR) motion sensor module, frequently used as a direct, higher-quality alternative to the common HC-SR501 . It uses the BISS0001 IC to process infrared signals into a digital output, offering better thermal stability and noise resistance than standard budget clones. Core Specifications PIR Motion Sensor: How It Works + Arduino Project - Zbotic hw416b pir sensor datasheet better
void setup() Serial.begin(9600); pinMode(PIR_PIN, INPUT); pinMode(LED_PIN, OUTPUT); If you bought a bundle of "HW-416B" PIR
PIR sensors are sensitive to power supply noise. Adding a 10uF electrolytic capacitor across the VCC and GND pins can significantly reduce "phantom" triggers caused by voltage ripples. or a starter kit