SmartElex Sound Detection Sensor

Overview

The SmartElex Sound Detection Sensor is a microphone-based audio sensing module designed to:

• Detect presence of sound

• Measure sound intensity (basic level)

• Provide digital and/or analog output signals

It is a low-level audio detection module, not a full audio processing or recording device.

Working Principle

The sensor operates using a combination of:

1. Electret Microphone

• Converts sound waves electrical signal (voltage)

• Responds to air pressure variations caused by sound

2. Signal Amplification

• Uses LM386 audio amplifier or LM393 comparator stage

• Amplifies weak microphone signals (up to ~200 gain)

3. ed signal with a preset reference level

If sound exceeds threshold:

• Digital output changes state (HIGH/LOW)

4. Output Generation

Analog Output (AOUT)

• Continuous voltage proportional to sound intensity

Digital Output (DOUT)

• Trigger signal when sound crosses threshold

This allows both:

• Sound level monitoring

• Event detection (e.g., clap)

Key Specifications

Electrical

• Operating voltage: 3.3V to 5.3V

• Low power consumption

• TTL-compatible output

Core Components

• Microphone: Electret condenser type

• Amplifier: LM386 or comparator LM393

Outputs

• Analog (AOUT): Sound level signital (DOUT): Threshold-based trigger

Physical

• Compact PCB (~45 21 mm typical)

• Lightweight (~5 g)

Pin Configuration

Typical 4-pin interface:

• VCC Power supply (3.3V5V)

• GND Ground

• DO (DOUT) Digital output

• AO (AOUT) Analog output

Some versions may only provide digital output.

Internal Features

Adjustable Sensitivity

• Often includes potentiometer

• Sets sound threshold level

Dual Output Capability

• Analog intensity measurement

• Digital event detection

Amplification Stage

• Detects even

  Sound Detection Process

  • Sound wave hits microphone

  • Converted to voltage

  • Amplified

  • Compared with threshold

  • Output generated

   

  Response Characteristics

  • Fast response (real-time detection)

  • Sensitive to nearby sounds (typically within ~0.5 m range)

   

  Environmental Influence

  • Affected by:

    • Ambient noise

    • Distance from sound source

    • Direction of sound

     

  Limitations

  • Cannot:

    • Identify sound type (voice, music, etc.)

    • Measure exact sound level in dB

     

  • Only detects:

    • Presence or relative intensity of sound

     

  • Sensitive to:

    • Electrical noise

    • Vibrations

     

    The module acts as a:

    • Sound presence detector

    • Basic audio intensity sensor

    • Trigger input device for control systems

     

    It is not a high-precision acoustic measurement instrument.

    Summary

    The SmartElex Sound Detection Sensor is a simple, compact audio sensing module that:

    • Uses a microphone + amplifier + comparator architecture

    • Provides analog and/or digital outputs

    • Operates at 3.3V5V

    • Detects sound presence and intensity changes

    • Is optimized for real-time sound-triggered systems</