●The LM4946 is an audio power amplifier capable of delivering 540mW of continuous average power into a mono 8Ω bridged-tied load (BTL) with 1% THD+N, 35mW 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 two-channel stereo signal and the third for a differential single-channel 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 I 2C or a three-wire SPI compatible 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 components in the OCL mode (two additional components in SE mode).
●## Key Specifications
●■ THD+N at 1kHz, 540mW into 8Ω BTL (3.3V) | 1.0% (typ)
●---|---
●■ THD+N at 1kHz, 35mW into 32Ω SE (3.3V) | 1.0% (typ)
●■ Single Supply Operation (VDD) | 2.7 to 5.5V
●■ I 2C/SPI Single Supply Operation |
● LLP | 2.2 to 5.5V
● micro SMD | 1.7 to 5.5V
● I 2C/SPI Control Interface
● I 2C/SPI programmable National 3D Audio
● I 2C/SPI controlled 32 step digital volume control (-54dB to +18dB)
● Three independent volume channels (Left, Right, Mono)
● Eight distinct output modes
● LLP and microSMD surface mount packaging
● “Click and Pop” suppression circuitry
● Thermal shutdown protection
● Low shutdown current (0.02uA, typ)
● RF immunity topology
