How to Use CA-6928 Bluetooth Audio: Examples, Pinouts, and Specs

The CA-6928 Bluetooth Audio module is a compact and versatile Bluetooth audio receiver designed for wireless audio streaming. It enables seamless connectivity between Bluetooth-enabled devices, such as smartphones, tablets, and laptops, and audio systems, such as speakers or amplifiers. This module is ideal for applications requiring high-quality audio transmission without the need for physical connections.

• Wireless audio streaming for home audio systems
• Integration into DIY Bluetooth speaker projects
• Car audio systems for hands-free music playback
• Audio upgrades for legacy sound systems
• Portable speaker designs

The CA-6928 Bluetooth Audio module is designed to deliver reliable performance with the following specifications:

The CA-6928 module features a simple pinout for easy integration into circuits:

1. Power the Module: Connect the VCC pin to a 3.7V-5.5V power source and the GND pin to ground.
2. Audio Output: Use the L_OUT and R_OUT pins to connect the module to an amplifier or speaker system. Alternatively, use the onboard 3.5mm AUX output if available.
3. Control Pin (KEY): Optionally, connect a push button to the KEY pin and ground. Pressing the button can initiate pairing or control playback (depending on the module's configuration).
4. Status LED: Connect an LED with a suitable current-limiting resistor to the LED pin to monitor the module's status (e.g., pairing, connected).

• Power Supply: Ensure a stable power supply within the specified voltage range to avoid damage to the module.
• Audio Quality: Use shielded cables for audio connections to minimize noise and interference.
• Placement: Avoid placing the module near sources of electromagnetic interference (e.g., motors, power supplies) to maintain a stable Bluetooth connection.
• Pairing: The module typically enters pairing mode automatically when powered on. Check the LED status to confirm pairing mode (blinking LED) or successful connection (steady LED).

The CA-6928 can be used with an Arduino UNO to control playback or pairing via the KEY pin. Below is an example code snippet:

// Example code to control the CA-6928 Bluetooth Audio module with an Arduino UNO
// This code toggles the KEY pin to initiate pairing or control playback.

const int keyPin = 7; // Connect the KEY pin of the CA-6928 to Arduino pin 7

void setup() {
  pinMode(keyPin, OUTPUT); // Set the KEY pin as an output
  digitalWrite(keyPin, HIGH); // Ensure the KEY pin is initially HIGH
}

void loop() {
  // Example: Simulate a button press to toggle playback or pairing
  digitalWrite(keyPin, LOW); // Pull the KEY pin LOW to simulate a button press
  delay(500); // Hold the LOW state for 500ms
  digitalWrite(keyPin, HIGH); // Release the button by setting the pin HIGH
  delay(5000); // Wait 5 seconds before the next action
}

1. No Audio Output:

   • Ensure the audio output pins (L_OUT and R_OUT) are properly connected to the amplifier or speakers.
   • Verify that the paired device is playing audio and the volume is not muted.

2. Bluetooth Connection Fails:

   • Check that the module is powered on and in pairing mode (blinking LED).
   • Ensure the device is within the 10-meter communication range.
   • Remove any previously paired devices from the Bluetooth settings of your smartphone or tablet and try pairing again.

3. Distorted Audio:

   • Verify that the power supply is stable and within the specified voltage range.
   • Use shielded cables for audio connections to reduce interference.

4. LED Not Working:

   • Confirm that the LED is connected to the LED pin with a suitable current-limiting resistor.
   • Check the polarity of the LED and ensure it is not damaged.

Q: Can the CA-6928 be powered by a USB port?
A: Yes, the module can be powered by a USB port as long as the voltage is within the 3.7V-5.5V range.

Q: Does the module support hands-free calling?
A: No, the CA-6928 is designed for audio streaming only and does not include a microphone for hands-free calling.

Q: Can I connect multiple devices to the module simultaneously?
A: No, the CA-6928 supports a single active Bluetooth connection at a time.

Q: How do I reset the module?
A: To reset the module, disconnect and reconnect the power supply. This will clear any active connections and restart the module.

By following this documentation, you can effectively integrate the CA-6928 Bluetooth Audio module into your projects and troubleshoot common issues with ease.