原标题：Atmel的 音频解决方案

　　该评估套件可让设计人员快速评估AT73C240的音频能力，并进行原型设计和测试新的设计。单机板便于利用示范软件产品评估。

　　基本特性：

　　The AT73C240 is a fully integrated, low-cost, combined stereo audio DAC and audio power amplifier circuit targeted for Li-Ion or Ni-Mh battery powered devices such as mobile phones, smartphones, PDA, DECT phones, digital still cameras, music players or any other type of handheld device where an audio interface is needed.

　　Stereo Audio DAC

　　– 2.7V to 3.3V Analog Supply Operation

　　– 2.4V to 3.3V Digital Supply Operation

　　– 20-bit Stereo Audio DAC

　　– 90 dB SNR Playback Stereo Channels

　　– 32 Ohm/20 mW Stereo Headset Drivers with Master Volume and Mute Controls

　　– Stereo Line Level Input with Volume Control/Mute and Playback through the Headset Drivers

　　– Accepts Mixed Signals from All Signal Paths (Line Inputs and DAC Output)

　　– 8, 11.024, 16, 22.05, 24, 32, 44.1 and 48 kHz Sampling Rates

　　– 256x or 384xFs Master Clock Frequency

　　– I2S Serial Audio Interface

　　Mono Audio Power Amplifier

　　– Supply Input from Main Li-Ion Battery (3V to 5.5V)

　　– 440 mW on 8 Ohm Load

　　– Programmable Volume Control (-22 to +20 dB)

　　– Fully Differential Structure, Input and Output

　　– 8 mA Drain Current in Active Mode

　　– Power-down Mode (Consumption Less than 2 μA)

　　– Minimum External Components (Direct Connection to the Loudspeaker)

　　 Applications: Mobile Phones, Digital Cameras, PDAs, SmartPhones, DECT Phones,Music Players

　　方案描述：

　　The evaluation kit lets designers quickly evaluate the audio capability of the AT73C240 and to prototype and test new designs. The standalone board allow easy product evaluation using demonstration software. Two serial interfaces (serial peripheral interface and I2S via a dedicated connector) boost its demonstration capabilities.

　　The AT73C240-EK1 provides the following features:

　　Power supply: – AC/DC transformer input (6V to 9V) – or External Power Supply pad On-board resources: – 20-bit stereo audio DAC, – 90dB SNR playback stereo channels, – 1 stereo 32 Ohm/20mW stereo headset (3.5mm jack connector), – 1 speaker 8 Ohms output (3.5mm jack connector), – 1 line stereo input (2 RCA) Serial interfaces: – SPI (by default), – TWI (by hardware modification), – I²S On-board buttons: – AT73C240 Reset, – SPI/TWI Communication, – TWI Address selection

　　参考原理图：

　　原理图1