SmartElex NS612 PIR Motion Sensor Module

🔹 Overview
The SmartElex NS612 PIR Motion Sensor Module is a digital passive infrared (PIR) motion detection module designed for human motion sensing.
Combines pyroelectric sensor + digital control circuitry
Outputs processed digital signal (no external conditioning required)
Designed for low-power embedded and IoT systems
🔹 Working Principle
Detects infrared radiation changes emitted by moving human bodies
Uses a pyroelectric sensing element
Signal flow:
IR change → analog signal
Internal amplifier + filter
ADC + digital processing → output signal
When signal crosses threshold → REL output triggered
🔹 Internal Architecture
Pyroelectric IR sensing element
High-impedance differential amplifier
Digital signal processing circuit
Electromagnetic shielding
Built-in band-pass filtering
👉 All signal processing is done on-chip
🔹 Electrical Characteristics
Operating Voltage: 2.2V – 3.7V
Static Current: < 11 µA (ultra-low power)
👉 Suitable for battery-powered devices
🔹 Detection Characteristics
Detection Range: up to 10 meters
Detection Angle: ~120° (horizontal)
Sensing Window: 3 × 4 mm
👉 Range depends on Fresnel lens used
🔹 Output Characteristics
Output Type: Digital (HIGH / LOW)
Signal Name: REL output
Behavior:
HIGH → Motion detected
LOW → No motion
👉 Direct interface with microcontrollers
🔹 Functional Features
Adjustable parameters (via onboard potentiometers):
Detection range
Response time
OEN (Enable Pin):
Controls output enable
Can integrate with light sensor or logic control
Built-in:
Noise filtering
RF interference suppression
Stable threshold detection
🔹 Performance Characteristics
High signal stability (low false triggers)
Short warm-up time
High power supply noise rejection
🔹 Functional Behavior
Detects only motion (dynamic IR changes)
Best detection when motion is:
Across the sensing field
Outputs a timed digital pulse after detection
🔹 Physical Characteristics
Dimensions: ~34 × 11 × 7 mm
Compact, lightweight module (~3g)
🔹 Key Technical Features
Integrated PIR + digital processing
Ultra-low power consumption (<11 µA)
Long detection range (~10 m)
Wide detection angle (120°)
Adjustable sensitivity and delay
Noise-resistant design
Direct digital output
🔹 Advantages
No external signal conditioning required
Easy integration with embedded systems
Flexible tuning (range + delay)
Stable performance in noisy environments
🔹 Limitations
Cannot detect stationary objects
Sensitive to:
Ambient temperature changes
External heat sources
Requires proper lens and positioning
Accuracy depends on calibration and environment
🔹 Technical Summary
The NS612 module is a smart PIR motion detection solution that:
Combines sensing + processing in one module
Provides reliable digital motion output
Is optimized for low-power, embedded, and automation systems