LM4946 Datasheet | National Semiconductor

Description The LM4946 is an audio power amplifier capable of delivering 540m W of continuous average power into a mono 8Ω bridged-tied load (BTL) with 1% THD+N, 35m W per channel of continuous average power into stereo 32Ω single-ended (SE) loads with 1% THD+N, or an output capacitor-less (OCL) configuration with identical specifications as the SE configuration, from a 3.3V power supply. The LM4946 has three input channels: one pair for a twochannel stereo signal and the third for a differential singlechannel mono input. The LM4946 features a 32-step digital volume control and eight distinct output modes. The digital volume control, 3D enhancement, and output modes (mono/ SE/OCL) are programmed through a two-wire I2C or a threewire SPI patible interface that allows flexibility in routing and mixing audio channels. The LM4946 is designed for cellular phone, PDA, and other portable handheld applications. It delivers high quality output power from a surface-mount package and requires only seven external ponents in the OCL mode (two additional ponents in SE mode). Key Specifications j THD+N at 1k Hz, 540m W into 8Ω BTL (3.3V) j THD+N at 1k Hz, 35m W 1.0% (typ) 1.0% (typ) 2.7 to 5.5V 2.2 to 5.5V into 32Ω SE (3.3V) j Single Supply Operation (VDD) j I2C/SPI Single Supply Operation Features n I2C/SPI Control Interface n I2C/SPI programmable National 3D Audio n I2C/SPI controlled 32 step digital volume control (-54d B to +18d B) n Three independent volume channels (Left, Right, Mono) n Eight distinct output modes n LLP surface mount packaging n “Click and Pop” suppression circuitry n Thermal shutdown protection n Low shutdown current (0.02u A, typ) n RF immunity topology Applications n Mobile Phones n PDAs Boomer ® is a registered trademark of National Semiconductor Corporation. © 2006 National Semiconductor Corporation DS201628 .national. Data Sheet 4 U . .. Typical Application 201628G1 FIGURE 1. Typical Audio Amplifier Application Circuit-Output...