MAX98357 I2S 3W Class D powerful Amplifier Interface Audio Decoder Module Filterless Board for Raspberry Pi, ESP32

About MAX98357

The MAX98357 I2S digital audio amplifier board is suitable for Raspberry Pi. Accepts digital audio through the I2S interface, converts it to an analog output signal, and amplifies it to allow direct speaker connection. It combines an I2S D/A converter with an audio amplifier on one board.

The small stereo amplifier module is surprisingly powerful and delivers up to 3.2W on 4Ω impedance speakers. The class D amplifier can be operated with a voltage of 2.7 V – 5.5 V. Due to the high efficiency of the amplifier, the module is particularly suitable for mobile and battery-powered projects.

The I2S audio input supports 3.3V and 5V levels. The gain can be set to the following values ​​using the gain input: 3dB, 6dB, 9dB, 12dB, and 15 dB.

By default, the stereo signals (L + R) are mixed to form an output signal. The behavior can be changed using a resistor so that only L or R is output. The MAX98357A/MAX98357B is an easy-to-use, low-cost,digital pulse-code modulation (PCM) input Class D amplifier that provides industry-leading Class AB audio performance with Class D efficiency. The digital audio interface automatically recognizes up to 35 different PCM and TDM clocking schemes which eliminates the need for I2C programming. Operation is further simplified by eliminating the need for an external MCLK signal that is typically used for PCM communication. Simply supply power, LRCLK, BCLK, and digital audio to generate audio! Furthermore, a novel pinout allows customers to use the cost-effective WLP package with no need for expensive vias (refer to Application Note 6643: Optimize Cost, Size, and Performance with MAX98357 WLP for more information). The digital audio interface is highly flexible with the MAX98357A supporting I2S data and the MAX98357B supporting left-justified data. Both ICs support 8 channel time division multiplexed (TDM) data. The digital audio interface accepts specified sample rates between 8kHz and 96kHz for all supported data formats. The ICs can be configured to produce a left channel, right channel, or (left/2 + right/2) output from the stereo input data. The ICs operate using 16/24/32-bit data for I2S and left-justified modes as well as 16-bit or 32-bit data using TDM mode. The ICs eliminate the need for the external MCLK signal that is typically used for PCM communication. This reduces EMI and possible board coupling issues in addition toreducing the size and pin count of the ICs.

The ICs also feature a very high wideband jitter tolerance (12ns typ) on BCLK and LRCLK to provide robust
operation. Active emissions-limiting, edge-rate limiting, and overshoot control circuitry greatly reduce EMI.

A filterless spread-spectrum modulation scheme eliminates the need for output filtering found in traditional Class D devices and reduces the component count of the solution.

Specifications of MAX98357 :

• 3.2 W output at 10% THD, 4 Ω impedance of the speaker, and 5 V power supply
• 2.7 – 5.5 V operating voltage
• 77 dB PSRR at 1 kHz
• Selectable gains: 3 dB, 6 dB, 9 dB, 12 dB, 15 dB

Features

• Single-Supply Operation (2.5V to 5.5V)
• 3.2W Output Power into 4Ω at 5V
•  2.4mA Quiescent Current
•  92% Efficiency (RL = 8Ω, POUT = 1W)
•  22.8μVRMS Output Noise (AV = 15dB)
• Low 0.013% THD+N at 1kHz
• No MCLK Required
• Sample Rates of 8kHz to 96kHz
• Supports Left, Right, or (Left/2 + Right/2) Output
• Sophisticated Edge Rate Control Enables
• Filterless Class D Outputs
• 77dB PSRR at 1kHz
• Low RF Susceptibility Rejects TDMA
• Noise from GSM Radios
• Extensive Click-and-Pop Reduction Circuitry
• Robust Short-Circuit and Thermal Protection
• Available in Space-Saving Packages:
• 1.345mm x 1.435mm WLP (0.4mm Pitch) and 3mm x 3mm TQFN

How to Use it 

• We have created a video that guides you how to use this module with ESP32 board to make your own Internet Radio and several other projects
• Package Includes:
  • 1 x MAX98357 I2S 3W Class D Amplifier Interface Audio Decoder Module Filterless Board For Raspberry Pi ESP32