How to Use PCM1822IRTER: Examples, Pinouts, and Specs

The PCM1822IRTER is a high-performance, low-power stereo analog-to-digital converter (ADC) manufactured by Texas Instruments. It is designed specifically for audio applications, offering a 24-bit resolution and supporting sampling rates of up to 192 kHz. This makes it ideal for high-fidelity audio processing in consumer electronics, professional audio equipment, and other audio systems.

The PCM1822IRTER integrates advanced digital filters and a flexible digital audio interface, simplifying its integration into a wide range of audio designs. Its low power consumption and compact size make it suitable for portable and space-constrained applications.

• Audio recording devices
• Professional audio equipment
• Consumer electronics (e.g., TVs, soundbars, and home theater systems)
• Voice recognition systems
• Musical instruments and audio effects processors

The PCM1822IRTER is available in a 16-pin WQFN package. Below is the pinout and description:

1. Power Supply: Connect the digital power supply (VDD) to 3.3 V and the analog power supply (VCCA) to either 3.3 V or 5 V, depending on your design requirements. Ensure proper decoupling capacitors are placed near the power pins.
2. Analog Inputs: Connect the audio signal to the differential or single-ended input pins (VINL+, VINL-, VINR+, VINR-). Use appropriate coupling capacitors to block DC components.
3. Clock Configuration: Provide a stable system clock (SCK) to the device. The clock frequency should match the desired sampling rate and audio interface configuration.
4. Digital Audio Interface: Configure the I²S, Left-Justified, or TDM interface using the LRCK, BCK, and DOUT pins. Ensure the host processor or microcontroller is configured to match the PCM1822IRTER's audio format.
5. I²C Communication: Use the SDA and SCL pins to configure the device via the I²C interface. This allows you to set parameters such as sampling rate, input gain, and digital filter options.
6. Reset: Use the RESET pin to initialize the device during power-up or after a fault condition.

• Grounding: Ensure a solid ground plane to minimize noise and interference.
• Decoupling: Place decoupling capacitors (e.g., 0.1 µF and 10 µF) close to the power supply pins to ensure stable operation.
• Input Impedance: Match the input impedance of the ADC to the source impedance for optimal performance.
• Clock Jitter: Minimize clock jitter to maintain high audio quality.
• Thermal Management: Although the PCM1822IRTER has low power consumption, ensure adequate thermal dissipation in high-temperature environments.

Below is an example of how to interface the PCM1822IRTER with an Arduino UNO using the I²C interface:

#include <Wire.h> // Include the Wire library for I²C communication

#define PCM1822_I2C_ADDRESS 0x4C // Default I²C address of PCM1822IRTER

void setup() {
  Wire.begin(); // Initialize I²C communication
  Serial.begin(9600); // Initialize serial communication for debugging

  // Reset the PCM1822IRTER
  pinMode(7, OUTPUT); // Assume RESET pin is connected to Arduino pin 7
  digitalWrite(7, LOW); // Hold RESET low
  delay(10); // Wait for 10 ms
  digitalWrite(7, HIGH); // Release RESET
  delay(10); // Wait for the device to initialize

  // Configure the PCM1822IRTER via I²C
  Wire.beginTransmission(PCM1822_I2C_ADDRESS);
  Wire.write(0x00); // Write to a configuration register (example)
  Wire.write(0x01); // Example value to configure the device
  Wire.endTransmission();

  Serial.println("PCM1822IRTER initialized.");
}

void loop() {
  // Main loop can handle audio data processing
}

1. No Output Signal:

   • Ensure the system clock (SCK) is stable and matches the required frequency.
   • Verify that the RESET pin is properly initialized during startup.
   • Check the I²C configuration to ensure the device is correctly set up.

2. Distorted Audio:

   • Verify that the input signal levels do not exceed the maximum input range of the ADC.
   • Check for proper grounding and minimize noise in the analog input path.
   • Ensure the clock jitter is within acceptable limits.

3. I²C Communication Failure:

   • Confirm the I²C address of the PCM1822IRTER matches the address used in the code.
   • Check the pull-up resistors on the SDA and SCL lines.

4. High Noise or Low SNR:

   • Ensure proper decoupling capacitors are used on the power supply pins.
   • Verify that the input impedance matches the source impedance.

Q: Can the PCM1822IRTER operate with a single-ended input?
A: Yes, the PCM1822IRTER supports both differential and single-ended inputs. For single-ended operation, connect the negative input pin (e.g., VINL-) to ground.

Q: What is the maximum sampling rate supported?
A: The PCM1822IRTER supports sampling rates of up to 192 kHz.

Q: Does the PCM1822IRTER require an external clock source?
A: Yes, the device requires a stable system clock (SCK) for proper operation. The clock frequency should match the desired sampling rate and audio interface configuration.

Q: Can the PCM1822IRTER be used in battery-powered devices?
A: Yes, its low power consumption (14 mW typical) makes it suitable for battery-powered applications.

This concludes the documentation for the PCM1822IRTER. For further details, refer to the official Texas Instruments datasheet.