The MAX98357A/MAX98357B are digital pulse-code mod-ulation （PCM） input Class D power amplifiers that provide Class AB audio performance with Class D efficiency. These ICs offer five selectable gain settings （3dB， 6dB， 9dB， 12dB， and 15dB） in I2S/left-justified mode set by a single gain select input and a fixed 12dB gain in TDM mode.

　　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 reduc-es EMI and possible board coupling issues in addition to reducing the size and pin count of the ICs.