Mini Basic PIR Sensor - BS412

Compact BS412 PIR motion sensor, self-contained with power, ground, and a resistor-set delay. Detects motion to ~5m; breadboard and perfboard friendly.

Pin 1 / GND1
Ground connection. Adafruit product page says to connect pin #1 to ground.
Type · groundVoltage · 0V
Pin 2 / on-time set2
On-time delay setting input. Adafruit says connect pin #2 to ground for an on time of 2 seconds, or use a resistor divider to set delay time.
Type · controlVoltage · 0V to 3.3V delay-setting input per Adafruit product page
Pin 3 / 3.3V3
3.3V power input. Adafruit product page says to connect pin #3 to 3.3V and run the sensor on 3.3V power.
Type · powerVoltage · 3.3V
Pin 4 / signal4
Digital PIR motion signal output. Adafruit says to check signal on pin #4 and describes the digital output as 3.3V high/low.
Type · signalVoltage · 3.3V logic high/low output per Adafruit product page

Start wiring

Analog · I2C · UART · 3.3 – 5 V · Breakout

Verify supply voltage and logic levels before powering up.

Module pins: Pin 3 / 3.3V, Pin 1 / GND, Pin 4 / signal. Schematik maps them to your board in the app.

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