MAX9814 Microphone Amplifier Module AGC Auto Gain Control 2.7-5.5V Arduino

🔧 MAX9814 Microphone Amplifier Module | AuscomTech

The MAX9814 Microphone Amplifier Module is a compact low-noise audio front-end board designed for capturing microphone signals for microcontroller and embedded audio projects.

It combines a low-noise preamplifier, variable gain stage, output amplifier, microphone bias generator, and automatic gain control (AGC) in one module to deliver a stable analog audio output.

This module is commonly used for voice detection, sound-reactive projects, audio sampling, and microphone input applications with Arduino, ESP32, and similar development platforms.

⭐ Key Features

• Automatic Gain Control – Built-in AGC helps maintain a more consistent output level across changing sound volumes.
• Low Noise Audio Front End – Designed for clear microphone signal amplification with low input-referred noise.
• Programmable Gain Options – Supports selectable total gain settings of 40dB, 50dB, or 60dB.
• Programmable Attack and Release Behaviour – Suitable for applications needing controlled AGC response timing.
• Wide Supply Range – Operates from 2.7V to 5.5V for easy integration with common logic supplies.
• Low THD Performance – Typical low distortion makes it suitable for audio sensing and voice input projects.
• Microcontroller Friendly – Analog output can be interfaced with ADC-capable boards for audio level monitoring and sampling.

📊 Technical Specifications

• Main IC: MAX9814
• Function: Microphone amplifier module with AGC
• Supply Voltage: 2.7V to 5.5V DC
• Gain Settings: 40dB, 50dB, 60dB
• Fixed Preamplifier Gain: 12dB
• AGC VGA Range: 20dB to 0dB
• Typical THD: 0.04%
• Input Noise Density: Up to 30nV/√Hz
• Microphone Bias: Internal low-noise bias, 2V
• Operating Temperature: -40°C to +85°C
• Output Type: Analog audio signal

🧩 Typical Applications

• Arduino and ESP32 audio input projects
• Voice and sound level detection
• Portable audio recorders
• Digital camera and headset audio circuits
• Intercom and teleconference devices
• Sound-reactive lighting and automation
• Embedded microphone front-end designs

⚠️ Important Notes

• This is an analog microphone amplifier module, not a digital microphone.
• Output should be connected to a suitable analog input or audio processing circuit.
• Not designed to drive speakers directly.
• Check board pin labels and supply voltage before wiring.
• Module layout or component placement may vary slightly between production batches.

📦 Package Includes

• 1 × MAX9814 Microphone Amplifier Module

🔗 Recommended Accessories (Not Included)

• Arduino or ESP32 board – for analog signal reading and processing
• Dupont jumper wires – for quick prototyping connections
• Breadboard – for testing and development
• 5V or 3.3V regulated power supply – for stable module operation