LM4935

The LM4935 is an integrated audio subsystem that supportsboth analog and digital audio functions. The LM4935 includesa high quality stereo DAC, a mono ADC, a multipurposeSAR ADC, a stereo headphone amplifier, whichsupports output cap-less (OCL) or AC-coupled (SE)modes ofoperation, a mono earpiece amplifier and a mono high efficiencyloudspeaker amplifier. It is designed for demandingapplications in mobile phones and other portable devices.The LM4935 features a bi-directional I2S serial interface forfull range audio and an I2C or SPI compatible interface forcontrol. The stereo DAC path features an SNR of 88 dB withan 18-bit 48 kHz input. In SE mode the headphone amplifierdelivers at least 33 mWRMS to a 32 single-ended stereoload 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 amplifierdelivers up to 600 mW into an 8 load with less than1% distortion when LS_VDD = 3.3V and up to 1.3W whenLS_VDD = 5.0V. The LM4935 also contains a general purposeSAR ADC for housekeeping duties such as battery and
temperature monitoring. This can also be used for analogvolume control of the output stages and can trigger interruptevents.

The LM4935 employs advanced techniques to reduce powerconsumption, to reduce controller overhead to speed developmenttime and to eliminate click and pop. Boomer audiopower amplifiers were designed specifically to provide highquality output power with a minimal amount of external components.It is therefore ideally suited for mobile phone andother low voltage applications where minimal power consumption,PCB area and cost are primaryrequirements.