The LM49370 is an integrated audio subsystem that supports both analog and digital audio functions. The LM49370 includes a high quality stereo DAC, a mono ADC, a stereo headphone amplifier, which supports output cap-less (OCL) or AC-coupled (SE) modes of operation, a mono earpiece amplifier, and an ultra-low EMI spread spectrum Class D loudspeaker amplifier. It is designed for demanding applications in mobile phones and other portable devices. The LM49370 features a bi-directional I2S interface and a bidirectional PCM interface for full range audio on either interface. The LM49370 utilizes an I2C or SPI compatible interface for control. The stereo DAC path features an SNR of 85 dB with an 18-bit 48 kHz input. In SE mode the headphone amplifier delivers at least 33 mWRMS to a 32 single-ended stereo load with less than 1% distortion (THD+N) when A_VDD = 3.3V. The mono earpiece amplifier delivers at least 115mWRMS to a 32 bridged-tied load with less than 1% distortion (THD+N) when A_VDD = 3.3V. The mono speaker amplifier delivers up to 490mW into an 8 load with less than 1% distortion when LS_VDD = 3.3V and up to 1.2W when LS_VDD = 5.0V.