MAX4466 Electret Microphone Amplifier with Adjustable Gain Module

MAX4466 Electret Microphone Amplifier with Adjustable Gain Module is a high-performance audio sensing solution specifically designed for projects requiring precise voice and ambient sound capture. This module utilizes the MAX4466 op-amp, which engineers optimized for use as a microphone preamplifier due to its excellent power-supply noise rejection. Consequently, the circuit delivers remarkably clean audio signals even when powered by potentially noisy digital supplies. The board features an integrated electret microphone and a small multi-turn potentiometer to adjust the gain from 25x to 125x. Furthermore, this flexibility allows you to tune the output to match various input requirements, ranging from loud environments to whisper-quiet recordings. Therefore, you can easily integrate this module into your next microcontroller-based audio project for reliable and adjustable sound detection.

Key Features:

• Adjustable Gain: The on-board trimmer potentiometer allows users to manually set the gain between 25x and 125x for diverse audio environments.
• Superior Noise Rejection: The MAX4466 IC provides high power-supply rejection ratio (PSRR), which ensures a low-noise output even in complex digital circuits.
• Rail-to-Rail Output: This feature enables the amplifier to provide a full-scale signal output, maximizing the dynamic range for analog-to-digital converters (ADCs).
• Ultra-Low Current: The module operates with a very low supply current, making it an ideal choice for battery-powered or portable electronic devices.
• Compact Form Factor: Its small PCB footprint allows for seamless integration into space-constrained enclosures and wearable technology.

Technical Specifications:

• Supply Voltage (V_CC): +2.4 V to +5.5 V DC
• Operating Current: ≈ 24 µA (Ultra-low power consumption)
• Gain Range: Adjustable from 25 V/V to 125 V/V
• Output Signal: Analog voltage (Rail-to-Rail)
• Power Supply Rejection Ratio (PSRR): 112 dB (Typical)
• Operating Temperature Range: −40°C to +85°C

Mechanical Specifications:

• Microphone Type: 6 mm Electret Condenser Microphone
• Potentiometer Type: Multi-turn trimmer for precise gain calibration
• PCB Material: Standard FR-4 glass epoxy with high-quality solder masking
• Mounting Hole: Includes one pre-drilled hole for secure mechanical fastening

Dimensions:

• PCB Length: ≈ 20 mm
• PCB Width: ≈ 14 mm
• Overall Height: ≈ 8 mm (including microphone and components)
• Weight: ≈ 2.5 g

Pinout and Wiring:

• VCC: Connect to a stable DC power source between 2.4 V and 5.5 V. However, for best results, use the quietest power supply available.
• GND: Connect to the common ground of your circuit.
• OUT: Connect this analog output pin directly to an ADC pin on your microcontroller (e.g., A0 on Arduino).

Datasheet Reference:

• Download MAX4466 Electret Microphone Amplifier Datasheet

Commonly Used in:

• Arduino and ESP32 Projects: Providing audio input for FFT-based music visualizers or sound-reactive LED strips.
• Voice Recognition Modules: Serving as a pre-amplification stage for speech-to-text or voice command interfaces.
• Environmental Monitoring: Monitoring noise pollution or detecting specific sound patterns in industrial settings.

Applications:

• Voice Changers: Capturing clean vocal data for real-time digital signal processing.
• Audio Recording: Acting as a sensitive input for small-scale voice recorders or spy gadgets.
• Smart Home Sensors: Triggering actions based on claps, knocks, or other acoustic events.
• Scientific Research: Measuring ultrasonic or low-frequency sound waves with appropriate gain settings.

Equivalent Models:

• MAX9814 Module: Offers automatic gain control (AGC), whereas the MAX4466 requires manual adjustment.
• CMA-4544PF-W: A standalone electret microphone that requires an external amplifier circuit.
• LM393 Sound Sensor: Typically used for digital sound detection (high/low) rather than full analog audio amplification.

Package Includes:

• 1 x MAX4466 Electret Microphone Amplifier with Adjustable Gain Module
• 1 x 3-Pin Straight Male Header Connector