AM312 Mini IR Pyroelectric Infrared PIR Motion Human Sensor

AM312 Mini IR Pyroelectric Infrared PIR Motion Human Sensor is an ultra-compact, highly efficient digital passive infrared module engineered explicitly for tight spaces and low-power applications. By relying on an advanced digital signal processing (DSP) core, this miniature sensor reliably detects the presence of moving human bodies while effectively rejecting environmental interference. Consequently, hardware developers frequently choose this diminutive component when building covert security nodes, miniature IoT smart home devices, and battery-run automatic lighting solutions where a standard HC-SR501 would simply be too large. Unlike its bulkier cousins, this module lacks physical adjustment potentiometers, instead relying on carefully calibrated, fixed factory settings for maximum stability. Furthermore, its impressively wide input voltage tolerance allows it to interface effortlessly with standard 3.3V microcontrollers as well as 12V systems. Therefore, whether you are concealing a motion alarm inside a doorbell or designing an automated pet feeder, the AM312 delivers flawless, zero-configuration motion detection.

Key Features:

• Microscopic Footprint: The incredibly small PCB layout allows the entire sensor to easily hide inside narrow plastic pipes, custom 3D printed housings, and lightbulb bases.
• Digital Intelligent Processing: Internal DSP circuitry actively filters out electronic noise and false thermal triggers, therefore drastically improving reliability over standard analog PIRs.
• Repeatable Trigger Mode: If continuous movement is detected within the sensing zone, the digital output remains locked HIGH until the subject completely vacates the area.
• Fixed Operating Parameters: Factory-set detection range and delay times eliminate the need for manual calibration tuning and consequently streamline mass production assembly.
• Wide Operating Voltage: The integrated electronics smoothly accept anything from a 2.7V lithium coin cell all the way up to a 12V automotive power supply.

Technical Specifications:

• Operating Voltage (V_IN): 2.7 V to 12.0 V DC
• Logic Output Voltage: 3.3 V (HIGH) / 0 V (LOW)
• Quiescent Current: ≤ 0.1 mA (Typically ∼ 15 μA in deep standby)
• Detection Angle: ≤ 100 degrees cone angle
• Detection Range: 3.0 meters to 5.0 meters (Fixed, non-adjustable)
• Delay Time: 2.0 seconds (Fixed, non-adjustable)
• Block Time: 2.0 seconds (Fixed period before a new trigger sequence initiates)
• Operating Temperature: −20°C to +60°C

Mechanical Specifications:

• Lens Material: White, high-density polyethylene (HDPE) micro-Fresnel dome lens
• Board Material: Multi-layer FR4 Fiberglass PCB
• Mounting Support: Devoid of mounting holes due to size limitations; typically secured by friction fitting the dome or using silicone adhesive on the PCB edges.
• Sensor Element: Integrated AM312 digital pyroelectric sensor
• Weight: ≈ 2.0 grams

Dimensions:

• Board Length: ≈ 10.0 mm
• Board Width: ≈ 8.0 mm
• Dome Diameter: ≈ 12.0 mm
• Total Height: ≈ 25.0 mm (Including dome and standard header pins)

Pinout and Wiring:

• VIN / VCC: Connect to your primary DC power supply (ranging from 2.7V to 12V).
• OUT: Connect this 3.3V digital logic line directly to an interrupt or input pin on your Arduino, ESP8266, or Raspberry Pi.
• GND: Connect firmly to the common ground of your power supply.
• Wiring Note: Due to its microscopic size, the pin labels are printed very faintly on the bottom of the PCB. However, strictly verify your VCC and GND connections before applying power, as reverse polarity will destroy the internal DSP chip.

Datasheet Reference:

• Download AM312 Mini PIR Sensor Datasheet

Commonly Used in:

• Smart Mirrors: Waking up hidden LCD displays instantly when a person steps in front of the vanity mirror.
• Battery-Powered Nightlights: Fitting inside compact, self-contained LED hallway pucks without draining the internal AAA batteries.
• Security Doorbell Cameras: Triggering the primary video recording sequence whenever a visitor approaches the front porch.

Applications:

• Interactive Advertising: Illuminating localized product display cases precisely when a shopper walks down the retail aisle specifically.
• Wearable Tech: Embedding into highly specialized safety garments to detect approaches in blind spots consequently.
• Vending Machines: Awakening the primary touchscreen interface from deep sleep mode strictly when a customer approaches.

Equivalent Models:

• SR602: Another hyper-compact PIR module boasting a slightly wider voltage range and an equally small fixed-lens profile.
• AS312: A nearly identical sibling sensor using the exact same DSP architecture and physical dimensions.
• HC-SR501: The larger, industry-standard PIR module however featuring adjustable delay times and distance sensitivity via bulky onboard potentiometers.

Package Includes:

• 1 x AM312 Mini IR Pyroelectric Infrared PIR Motion Human Sensor