describe

MAX98357A/MAX98357B is an easy-to-use, low-cost, digital pulse code modulation (PCM) input Class D amplifier that provides industry-leading AB level audio performance and Class D efficiency. This digital audio interface can automatically recognize up to 35 different PCM and TDM clock schemes, eliminating the need for I2C programming.

By eliminating the need for external MCLK signals commonly used for PCM communication, the operation is further simplified. Simply provide power, LRCLK, BCLK, and digital audio to generate audio! In addition, a new suite allows customers to use cost-effective WLP software packages without the need for expensive channels (see application instructions 6643: Optimizing Cost, Size, and Performance with MAX98357 WLP).

The digital audio interface is highly flexible, with MAX98357A supporting I2S data and MAX98357B supporting left positive data. Both integrated circuits support 8-channel time-division multiplexing (TDM) data. For all supported data formats, the digital audio interface accepts a specified sampling rate between 8 kHz and 96 kHz.

Integrated circuits can be configured to generate left channel, right channel, or (left/2+right/2) output from stereo input data. Integrated circuits use 16/24/32-bit data for I2S mode and left pass mode, as well as 16 bit or 32-bit data for TDM mode. Integrated circuits eliminate the need for external MCLK signals typically used for PCM communication. This reduces electromagnetic interference and potential board coupling issues, in addition to reducing the size and pin count of integrated circuits.

The integrated circuit also has a very high broadband jitter tolerance (12ns typ) on BCLK and LRCLK to provide powerful operation.

Active emission limitation, edge rate limitation, and overshoot control circuits greatly reduce electromagnetic interference. A unfiltered spread spectrum modulation scheme eliminates the need for output filtering in traditional D-class devices and reduces the component count of the solution.

The integrated circuit comes in 9-pin WLP (1.345mm x 1.435mm x 0.64mm) and 16 pin TQFN (3mm x 3mm x 0.75mm) packages, and is specified within the temperature range of -40 ° C to+85 ° C.

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)
● 25μVRMS Output Noise (AV = 15dB)
● Low 0.015% 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
● Solution Size with Single Bypass Capacitor is 
4.32mm2
Applications
● Single Li-ion Cell/5V Devices 
● Smart Speakers
● Notebook Computers 
● IoT Devices
● Gaming Devices (Audio and Haptics)
● Smartphones 
● Tablets 

● Cameras