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CJMCU-TRRS 3.5mm Jack AV Stereo Module

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Ekostra Electronics

On April 13, 2025

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CJMCU-TRRS 3.5mm Jack AV Stereo Module

Compact breakout board for audio/video signal interfacing with TRRS connectors

Introduction

The CJMCU-TRRS is a compact breakout module featuring a standard 3.5mm TRRS (Tip-Ring-Ring-Sleeve) jack for audio and video signal interfacing. This module simplifies connections between microcontrollers and audio/video devices.

Key Features

🎧 TRRS Interface

Standard 4-pole 3.5mm audio/video jack

🔊 Stereo Audio

Left and right channel support

📹 Video Support

Composite video signal capability

🔌 Breakout Pins

Easy access to all signal lines

Technical Specifications

Jack Type	3.5mm TRRS (CTIA standard)
Connections	Tip: Left Audio, Ring1: Right Audio, Ring2: Ground, Sleeve: Video/Mic
PCB Dimensions	20mm × 15mm × 6mm
Pin Spacing	2.54mm standard header
Compatibility	Arduino, Raspberry Pi, most microcontrollers

Pin Configuration

Pin Label	Function	TRRS Connection
L	Left Audio Channel	Tip
R	Right Audio Channel	Ring 1
GND	Ground	Ring 2
V/M	Video or Microphone	Sleeve

Note: The V/M pin serves dual purpose – video output when used as AV, or microphone input when used for audio applications.

Basic Wiring with Arduino

// Simple Audio Output Example
const int audioPin = 9; // PWM pin for audio output

void setup() {
  pinMode(audioPin, OUTPUT);
}

void loop() {
  // Generate simple tone
  tone(audioPin, 440, 500); // 440Hz for 500ms
  delay(1000);
}

// Simple Audio Output Example

const int audioPin = 9; // PWM pin for audio output

void setup() {

pinMode(audioPin, OUTPUT);

}

void loop() {

// Generate simple tone

tone(audioPin, 440, 500); // 440Hz for 500ms

delay(1000);

}

Common Applications

Audio Output

Connect to headphones or external speakers for sound output from microcontrollers.

Video Output

Interface with displays that accept composite video input.

Audio Input

Capture microphone input when configured for audio recording.

Troubleshooting

No Audio Output

Verify TRRS plug is fully inserted
Check wiring to correct audio channels
Ensure audio signal is being generated

Poor Audio Quality

Use proper amplification for speaker output
Ensure clean power supply
Check for loose connections

Video Signal Issues

Confirm device supports composite video
Verify correct video standard (NTSC/PAL)
Check cable quality and connections

Project Ideas

MP3 Player

Build an Arduino-based music player with headphone output

Video Game Console

Create a retro gaming system with composite video output

Voice Recorder

Develop a simple audio recording device

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CJMCU-TRRS 3.5mm Jack AV Stereo Module

CJMCU-TRRS 3.5mm Jack AV Stereo Module

Introduction