How to Use Adafruit Stereo 2.8W Class D Audio Amplifier - I2C Control AGC - TPA2016: Examples, Pinouts, and Specs

The Adafruit Stereo 2.8W Class D Audio Amplifier with I2C Control AGC, featuring the TPA2016D2 chip, is a sophisticated audio amplification solution designed for projects that require high-quality sound in a compact form factor. This amplifier is capable of delivering up to 2.8 watts per channel into 4-ohm speakers. With its I2C interface, users can digitally control volume and configure the automatic gain control (AGC) settings, making it ideal for a wide range of applications such as DIY speakers, portable audio devices, and interactive installations.

• Stereo output: 2.8W per channel into 4Ω
• Class D operation: Highly efficient and low heat generation
• I2C control interface: Digital volume and AGC configuration
• Supply voltage: 2.7V to 5.5V
• PSRR: 77 dB at 217 Hz with AGC disabled
• THD+N: 0.02% at 1W into 8Ω
• SNR: 90 dB (typical A-weighted)
• AGC and compression settings: Adjustable via I2C

1. Power Supply: Connect the Vin pin to a 2.7V to 5.5V power source and the GND pin to the ground.
2. Speaker Connection: Connect your 4Ω speakers to the L+ and L- for the left channel, and R+ and R- for the right channel.
3. I2C Communication: Connect the SCL and SDA pins to your microcontroller's I2C clock and data lines, respectively.
4. Shutdown Control (Optional): Connect the SD pin to a GPIO on your microcontroller if you wish to control the shutdown mode programmatically.

• Use a decoupling capacitor close to the Vin pin to filter out voltage spikes.
• Ensure that the speakers are rated for the output power of the amplifier to prevent damage.
• Keep the audio input signal within the recommended levels to avoid distortion.
• Use shielded cables for I2C communication to reduce noise pickup.

#include <Wire.h>
#include <Adafruit_TPA2016.h>

Adafruit_TPA2016 audioamp;

void setup() {
  Wire.begin(); // Join I2C bus
  audioamp.begin(); // Initialize the amplifier

  audioamp.setAGCCompression(TPA2016_AGC_OFF); // Disable AGC
  audioamp.setGain(30); // Set gain to 30dB
}

void loop() {
  // Your code to control the amplifier
}

• No Sound Output: Ensure that the speakers are properly connected and the amplifier is powered.
• Distorted Sound: Check if the input signal level is too high and adjust the gain settings.
• I2C Communication Failure: Verify the connections to SCL and SDA pins and check for correct pull-up resistors.

Q: Can I use 8Ω speakers with this amplifier? A: Yes, but the output power will be lower than with 4Ω speakers.

Q: How do I change the I2C address? A: The I2C address can be changed by connecting the ADR pin to Vin or GND.

Q: What is the default I2C address? A: The default I2C address is 0x58.

Q: Can the amplifier run on a 3.3V supply? A: Yes, the amplifier can operate on a supply voltage as low as 2.7V.

Q: How do I enable the AGC feature? A: AGC can be enabled and configured through the I2C interface using the Adafruit_TPA2016 library.

For further assistance, consult the Adafruit support forums or the detailed datasheet for the TPA2016D2 chip.