基于单片机控制的DDS信号源设计  

Design of DDS Signal Source Based on MCU

作　　者：查荣[1] 

机构地区：[1]无锡工艺职业技术学院,江苏宜兴214206

出　　处：《机械制造与自动化》2011年第1期135-137,共3页Machine Building & Automation

摘　　要：介绍了直接数字频率合成(DDS)信号源的设计。该系统分成3个主要模块,分别是:直接数字频率模块,键盘和LCD控制模块和低通椭圆滤波模块。基于单片机有足够的空闲输入输出引脚,DDS模块中的AD9851采用并行工作模式。在低通椭圆滤波模块,采用了基于反归一法设计的截止频率为25MHz的低通椭圆滤波器。最后附上了电路图和系统产生的波形图。In this paper,a design of signal source of direct digital frequency synthesis（DDS） is presented.The system is divided into three main modules;DDS module,keyboard and LCD control module and low-pass elliptic filter module.In DDS module,AD9851 is designed to work in parallel mode for the MCU which can provide enough free I/O pins for it.In low-pass elliptic filter module,a new design of a low pass filter of 25MHz of cut-off frequency is proposed by antinormalization.The circuit diagram and waveform diagram of the device are shown in the end of the paper.

关 键 词：直接数字频率合成器 AD9851 椭圆低通滤波器 

分 类 号：TN743[电子电信—电路与系统]