MAX4466 Electret Microphone Amplifier Module with Adjustable Gain

MAX4466 Electret Microphone Amplifier Module Audio developers and electronics hobbyists utilize this high-performance preamplifier board to capture ambient sound and convert it into clean voice signals for microcontrollers. Consequently, it integrates a low-noise Maxim MAX4466 op-amp with a high-sensitivity electret capsule and an onboard trimmer to provide fully adjustable output gain. Therefore, this compact breakout board serves as an exceptional choice for voice changers, audio recording suites, and acoustic FFT frequency analysis projects.

Key Features:

• Adjustable Gain Control: Features a backside-mounted trim potentiometer allowing smooth gain adjustment from 25x to 125x to match diverse microcontroller ADC requirements.
• Excellent Power Supply Rejection: Built with exceptional power supply noise rejection (PSRR) to deliver ultra-clean audio amplification without hum or ripple from digital logic.
• Ultra-Low Audio Distortion: Employs an optimized operational amplifier topology ensuring minimal harmonic distortion for accurate acoustic monitoring.
• Integrated Electret Capsule: Comes pre-soldered with a high-sensitivity microphone capsule optimized for picking up standard vocal ranges and environmental acoustics.
• Breadboard-Friendly Form Factor: Features a small three-pin layout that fits perfectly into standard breadboards and compact DIY project enclosures.

Technical Specifications:

• Operating Voltage: 2.4 V to 5.5 V DC.
• Core Operational Amplifier IC: Maxim Integrated MAX4466.
• Gain Range Profile: Adjustable from 25× to 125× via onboard trim pot.
• Output Profile: Analog rail-to-rail voltage signal (ideal for ADC reading).
• Frequency Response: 20 Hz to 20 kHz.
• Power Supply Rejection Ratio (PSRR): 112 dB typical for stable low-noise execution.

Mechanical Specifications:

• PCB Layout Style: Single-sided low-profile SMD population with through-hole interface pads.
• Solder Mask Color: Vibrant purple or dark blue mask featuring clear white component designations.
• Microphone Assembly: Directly edge-mounted and fixed securely to the PCB to resist microphonic vibrations.

Dimensions:

• PCB Length: ≈ 20.00 mm.
• PCB Width: ≈ 14.00 mm.
• Total Module Height: ≈ 8.00 mm (including the depth of the electret capsule).
• Total Module Weight: ≈ 3.00 g (Ultra-light profile ideal for miniature audio recorders or wearables).

Pinout and Wiring:

• VCC Pad: Connects to a clean, filtered positive supply line between 2.4V and 5.5V DC (3.3V recommended for quietest performance).
• GND Pad: System audio and power ground reference point.
• OUT Pad: Audio signal output delivering an analog AC wave riding on a DC bias of VCC/2 to link directly into an ADC input pin.

Datasheet Reference: Download Datasheet

• MAX4466 Low-Noise Electret Microphone Amplifier Module Schematic and Gain Calculation Guide

Commonly Used in:

• Voice-Activated Controllers: Serving as the front-end acoustic sensor for voice-responsive relays or home automation control hubs.
• Audio Sampling Projects: Interfacing with Arduino, ESP32, or Raspberry Pi boards to execute FFT spectrum calculations and audio-reactive LED matrices.
• Spy Bug & Recording Suites: Acting as a low-power, high-gain preamplifier stage for miniature audio recording devices and dictaphones.

Applications:

• Acoustic Monitoring and Decibel Metering: Capturing environmental decibel metrics or sampling local frequencies for noise-pollution analysis trackers. However, connecting the VCC pin to a noisy or unshielded digital power rail can introduce severe audio hum and false ADC triggers; therefore, engineers should ideally utilize a dedicated linear voltage regulator or place a decoupling capacitor across the supply pins.

Equivalent Models:

• MAX9814 Microphone Amplifier: An advanced alternative featuring built-in Automatic Gain Control (AGC) and selectable compression settings.
• KY-038 Microphone Sensor Board: A simpler comparator-based digital switch module that only outputs high/low logic gates rather than continuous analog waveforms.

Package Includes:

• 1 × MAX4466 Electret Microphone Amplifier Board