原标题：Nuvoton ISD61S00 PSTN系统解决方案

　　Nuvoton 公司的ISD61S00是PSTN电话通信系统的特征芯片,器件包括了音频存储功能以及基于数据的通信功能,包括DTMF检测和发生,75-1200波特的FSK调制解调器功能,CAS和CPT检测于铃声检测.音频通路能和PSTN系统的线路侧和麦克风侧接口,包括全双工和半双工以及线路回声消除功能,数字音频接口可配置成 I2S或PCM模式以适应数字串行音频通信.本文介绍了ISD61S00主要特性, 方框图以及典型应用电路和系统方框图.

　　The ISD61S00 is a feature chip for the security and telephony industry. The device incorporates audio storage with a powerful macro scripting ability to facilitate audio prompting in a multi-language environment and simple address-free recording and playback. It utilizes external serial flash memory for audio data storage. In addition, the device includes circuitry to perform telephony based data communications including DTMF detection and generation, FSK modem functions from 75-1200 baud, CAS and CPT (Call Progress Tone) detection and ring detection. The audio path of the device is designed to interface to both the air side and line side of a PSTN system. The air side includes a flexible microphone interface incorporating a bias generator and gain control and a differential analog output for driving a speaker or power amplifier. The line side incorporates a line driver to drive PSTN loads and two variable gain differential inputs. The audio path includes full and half-duplex acoustic and line echo cancellation to implement full and half-duplex speakerphone functions. The digital audio interface can be configured to I2S or PCM mode for digital serial audio communication. Control, monitoring and device programming is perfomed via a SPI interface. The device package is LQFP-48L.

　　ISD61S00主要特性:

　　图1.ISD61S00方框图

　　图5.ISD61S00系统方框图