原标题：ADI ADAU1787Z低功耗音频DSP解决方案

　　ADI公司的ADAU1787Z是集成了两个低功耗音频DSP的和两个输入和一个输出的CODEC,模拟输入到DSP核到模拟输出的通路进行优化,以到到低等待和非常适合于手持设备的噪音消除.仅需要增几个外接的无源元件, ADAU1787Z就提供噪音消除耳机解决方案.ADAU1787Z具有可编程FastDSP音频处理引擎,高达768kNz取样速率.器件具有双四元滤波器,限幅器,音量控制和混合器,28位SigmaDSP音频处理核,高达50MIPS性能,低等待24位ADC和DAC,96dB SNR(信号通过带A加权滤波器的PGA和ADC),105dB组合SNR(信号通过带A加权滤波器DAC和耳机),频率8kHz到768kHz的串口fSYNC,模拟输入到模拟输出的群时延5μs(取样频繁768kHz),PLL支持30kHz到27MHz的任何输入时钟速率,具有全双工4路ASRC,主要用于噪音消除的手持设备和耳机,蓝牙ANC手持设备和耳机,个人导航设备(PNA),数码相机和视频摄像机,乐器效应处理器,多媒体扬声器系统和智能手机.本文介绍了ADAU1787Z主要特性,功能框图,以及评估板EVAL-ADAU1787Z主要特性,电路图,材料清单和PCB设计图.

　　The ADAU1788 is a codec with two inputs and one output that incorporates two digital signal processors (DSPs). The path from the analog input to the DSP core to the analog output is optimized for low latency and is ideal for noise cancelling headsets. With the addition of just a few passive components, the ADAU1788 provides a noise cancelling headphone solution.

　　Note that throughout this data sheet, multifunction pins, such as BCLK_0/MP1, are referred to either by the entire pin name or by a single function of the pin, for example, BCLK_0, when only that function is relevant.

　　ADAU1787Z主要特性:

　　Programmable FastDSP audio processing engine

　　Up to 768 kHz sample rate

　　Biquad filters, limiters, volume controls, mixing

　　28-bit SigmaDSP audio processing core

　　Visually programmable using SigmaStudio

　　Up to 50 MIPS performance

　　Low latency, 24-bit ADCs and DAC

　　96 dB SNR (signal through PGA and ADC with A-weighted filter)

　　105 dB combined SNR (signal through DAC and headphone with A-weighted filter) Serial port fSYNC frequency from 8 kHz to 768 kHz

　　5 μs group delay (fS = 768 kHz) analog in to analog out

　　2 single-ended analog inputs, configurable as microphone or line inputs

　　4 digital microphone inputs

　　1 analog differential audio output, configurable as either line output or headphone driver

　　PLL supporting any input clock rate from 30 kHz to 27 MHz

　　Full-duplex, 4-channel ASRCs

　　16-channel serial audio port supporting I2S, left justified, or up to TDM16

　　8 interpolators and 8 decimators with flexible routing

　　Power supplies

　　Analog AVDD at 1.8 V typical

　　Digital I/O IOVDD at 1.1 V to 1.98 V

　　Digital DVDD at 0.9 V typical

　　Low power (8.030 mW for typical power consumption)

　　I2C and SPI control interfaces

　　Flexible GPIO

　　42-ball, 0.35 mm pitch, 2.695 mm×2.320 mm WLCSP

　　ADAU1787Z应用:

　　Noise cancelling handsets, headsets, and headphones

　　Bluetooth ANC handsets, headsets, and headphones

　　Personal navigation devices

　　Digital still and video cameras

　　Musical instrument effect processors

　　Multimedia speaker systems

　　Smartphones

　　图1. ADAU1787Z功能框图

　　图2. ADAU1788带模拟麦克风自引导模式的系统框图

　　评估板EVAL-ADAU1787Z

　　Evaluating the ADAU1787 Four-ADC, Two-DAC, Low Power Codec with Audio DSPs This user guide explains the design and setup of the EVAL-ADAU1787Z evaluation board.

　　This evaluation board provides access to all analog and digital inputs/outputs on the ADAU1787. The ADAU1787 core is controlled by Analog Devices, Inc., SigmaStudio® software, which interfaces to the EVAL-ADAU1787Z via a USB connection.The EVAL-ADAU1787Z can be powered by the USB bus or by a single 3.8 V to 5 V supply. Any of these supplies are regulated to the voltages required on the EVAL-ADAU1787Z. The printed circuit board (PCB) is a 6-layer design, with a ground plane and a power plane on the inner layers. The EVAL-ADAU1787Z contains connectors for external microphones and speakers. The master clock can be provided externally or by the on-board 24.576 MHz passive crystal.

　　Multifunction pin names may be referenced by their relevant function only, for example, MPx, throughout this user guide.

　　评估板EVAL-ADAU1787Z包括:

　　EVAL-ADAU1787Z evaluation board

　　EVAL-ADUSB2EBZ (USBi) communications adapter

　　USB cable with mini USB plug

　　图.评估板EVAL-ADAU1787Z外形图

　　图.评估板EVAL-ADAU1787Z电路图:ADAU1787

　　图.评估板EVAL-ADAU1787Z电路图:电源

　　评估板EVAL-ADAU1787Z材料清单: