LM49101 Datasheet | National Semiconductor

Description The LM49101 is a fully integrated audio subsystem with a mono power amplifier capable of delivering 540m W of continuous average power into an 8Ω BTL speaker load with 1% THD+N using a 3.3V supply. The LM49101 includes a separate stereo headphone amplifier that can deliver 44m W per channel into 32Ω loads using a 2.75V supply. The LM49101 has four input channels. A pair of single-ended inputs and a fully differential input channel with volume control and amplification stages. Additionally, a bypass differential input is available that connects directly to the mono speaker outputs through an analog switch without any amplification or volume control stages. The LM49101 features a 32- step digital volume control on the input stage and an 8- step digital volume control on the headphone output stage. The digital volume control and output modes, programmed through a two-wire I2C patible interface, allows flexibility in routing and mixing audio channels. The LM49101 is designed for cellular phones, PDAs, and other portable handheld applications. The high level of integration minimizes external ponents. The True Ground headphone amplifier eliminates the physically large DC blocking output capacitors reducing required board space and reducing cost. -  Output Power   VDDLS = 3.3V, VDDHP = 2.75V   1% THD+N RL = 8Ω speaker RL = 32Ω headphone 540W (typ) 40m W (typ) -  PSRR:   VDD = 3.3V, 217Hz ripple, Mono In -  Shutdown power supply current 90d B (typ) 0.01μA (typ) Features - - - - - - - - - - - - - - - Differential mono input and stereo single-ended input Separate earpiece (receiver) differential input Analog switch for a separate earpiece path 32-step digital volume control (-80 to +18d B) Three independent volume channels (Left, Right, Mono) Separate headphone volume control Flexible output for speaker and headphone output True Ground headphone amplifier eliminates large DC blocking capacitors reducing PCB space and cost. Hardware reset function RF immunity topology...