# KS6085 KS0599 KS0600 keyestudio I2S Audio Power Amplifier Module
![0](./media/0.png)

## 1.Description

This module is equipped with the MAX98375 as the main control chip. It is a highly efficient, low-noise and highly integrated D-class audio power amplifier, which is particularly suitable for portable audio devices with high requirements for power consumption and anti-interference. Its I2S digital input, anti-distortion function and rich protection mechanisms make it have broad applications in consumer electronic products.

## 2.Parameters

- I2S serial digital audio input interface
- Supports wide-range sampling rates: 8kHz to 96kHz
- Automatic sampling rate detection, self-adaption
- Built-in digital high-pass filter, a single pulse sets its turning point
- Optional left and right channels can be set by pressing CTRL to the pin level
- Anti-distortion NCN function
- Class D amplifier without filter
- Output power: 2.5W(VDD=5V, RL=4Ω)
- Operating voltage range: 3.0V to 5.5V
- 0.2% THD (VDD=5V, RL=4Ω, Po=1W)
- 80% efficiency (VDD=5V, RL=4Ω, Po=2.5W)
- Excellent noise suppression for “power-on and power-off”
- Overcurrent protection, overheat protection, under-voltage protection
- eSOP8 packaging
- Dimensions: 48 *24mm
- Weight: 6.96g

## 3.Schematic Diagram

![1](./media/1.png)

## 4.Connection Diagram

|            **Module**            | QTY  |
| :------------------------------: | :--: |
|    Kidsbits ESP32-Dev-Module     |  1   |
| I2S audio power amplifier module |  1   |
|         M-F DuPont wire          |  5   |
|        Type C data cable         |  1   |
|             Speaker              |  1   |

| Amplifier module | ESP32 |
| :---------------: | :---: |
|        VCC        |  3V3/5V  |
|        GND        |   G   |
|       BCLK        | io19  |
|       LRCK        | io17  |
|       DOUT        | io18  |

![10](./media/10.png)

Connect either of the two interfaces at the back of the module to a speaker. After burning the program, the experimental effect can be achieved.

## 5.Environment Configuration & Sample Code

**Arduino IDE (Windows)**

First, let's go to the download website of Arduino official software: https://www.arduino.cc/en/software/#ide.   

Download the latest version of the Arduino development software. After entering the website, it is as shown in the following figure:

There are many versions of Arduino, including those for Windows,mac and linux systems, as well as older ones.You just need to download a version that suits your system.

![12](./media/12.png)

Here, we take the Windows system as an example to introduce the steps of downloading and installing. There are also two versions of the Windows system: one for installation, one for download(no need to install and just unzip it to use).

![13](./media/13.png)

Click JUST DOWNLOAD.

**Environment Configuration**

First, open the Arduino IDE,Install the corresponding development board platform.

![4](./media/4.png)

 select Development Board, the port number and the corresponding development board platform.

![2](./media/2.png)

![3](./media/3.png)



In the menu, click on “File” to find “Preferences” and “Enter”, and then enter “https://espressif.github.io/arduino-esp32/package_esp32_index.json” in “Other Development Board Management” and click OK.

![9](./media/9.png)

![5](./media/5.png)

Next, install the required driver libraries. Enter “ESP32-audioI2S-master” in the library management box to install the corresponding library file.

![6](./media/6.png)

Then copy the following code to the editing box and upload it to the ESP32 board via ArduinoIDE.

```c
#include <driver/i2s.h>

#define I2S_PORT I2S_NUM_0

// Audio parameter configuration
#define SAMPLE_RATE     44100    // Sampling rate (Hz)
#define BITS_PER_SAMPLE 16       // Sampling bit number
#define BUFFER_SIZE     1024     // Buffer size

// Ambulance siren parameters
#define LOW_FREQ        500      // Low frequency (Hz)
#define HIGH_FREQ       700      // High frequency (Hz)
#define SWEEP_TIME      1000     // Frequency variation period (ms)

// Audio buffer
int16_t audioBuffer[BUFFER_SIZE];
int bufferIndex = 0;
bool isHighFreq = false;
unsigned long lastSweepTime = 0;

// I2S pin configuration (Modify according to actual connection)
#define I2S_MCLK_PIN    I2S_PIN_NO_CHANGE  // There are no MCLK pins
#define I2S_BCLK_PIN    19
#define I2S_LRCK_PIN     17
#define I2S_DOUT_PIN    18
#define I2S_DATA_IN_PIN I2S_PIN_NO_CHANGE

void setup() {
  Serial.begin(115200);
  
  // Configure the I2S parameters
  i2s_config_t i2s_config = {
    .mode = (i2s_mode_t)(I2S_MODE_MASTER | I2S_MODE_TX),
    .sample_rate = SAMPLE_RATE,
    .bits_per_sample = (i2s_bits_per_sample_t)BITS_PER_SAMPLE,
    .channel_format = I2S_CHANNEL_FMT_ONLY_LEFT,
    .communication_format = I2S_COMM_FORMAT_STAND_I2S,
    .intr_alloc_flags = ESP_INTR_FLAG_LEVEL1,
    .dma_buf_count = 8,
    .dma_buf_len = BUFFER_SIZE,
    .use_apll = false,
    .tx_desc_auto_clear = true,
    .fixed_mclk = 0  // Disable the fixed MCLK
  };
  
  // Configure the I2S pins
  i2s_pin_config_t pin_config = {
    .bck_io_num = I2S_BCLK_PIN,
    .ws_io_num = I2S_LRCK_PIN,
    .data_out_num = I2S_DOUT_PIN,
    .data_in_num = I2S_DATA_IN_PIN
  };
  
  // Install and start the I2S driver
  i2s_driver_install(I2S_PORT, &i2s_config, 0, NULL);
  i2s_set_pin(I2S_PORT, &pin_config);
  i2s_start(I2S_PORT);
  
  Serial.println("The ambulance siren simulator has been activated");
}

// Generate the waveform of the ambulance siren
void generateSirenWaveform(int16_t* buffer, int size, float frequency) {
  float amplitude = 16000.0;  // Volume level(0-32767)
  float phase = 0.0;
  float phaseIncrement = 2.0 * PI * frequency / SAMPLE_RATE;
  
  for (int i = 0; i < size; i++) {
    // Generate a sine wave
    buffer[i] = (int16_t)(amplitude * sin(phase));
    phase += phaseIncrement;
    
    // Deal with phase overflow
    if (phase > 2.0 * PI) {
      phase -= 2.0 * PI;
    }
  }
}

void loop() {
  // Check whether the frequency needs to be switched
  if (millis() - lastSweepTime > SWEEP_TIME) {
    isHighFreq = !isHighFreq;
    lastSweepTime = millis();
    Serial.print("Switching frequency: ");
    Serial.println(isHighFreq ? "High frequency" : "Low frequency");
  }
  
  // Generate the waveform of the current frequency
  float currentFreq = isHighFreq ? HIGH_FREQ : LOW_FREQ;
  generateSirenWaveform(audioBuffer, BUFFER_SIZE, currentFreq);
  
  // Send the waveform data to the I2S interface
  size_t bytesWritten = 0;
  i2s_write(I2S_PORT, audioBuffer, BUFFER_SIZE * sizeof(int16_t), &bytesWritten, portMAX_DELAY);
}

```

![7](./media/7.png)

## 6.Test Result

After the burning and uploading the code, the ambulance siren sound will be produced, alternating between two frequencies. It sounds like “woo ~ wah ~ woo ~ wah ~”. The serial monitor will print the following data, as shown below:

![8](./media/8.png)