文档介绍：数字式正弦波信号发生器的设计与实现
摘要
正弦交流信号是一种应用极为广泛的信号。在许多测试仪中需要用标准的正弦信号检测一些物理量。正弦信号用作标准信号时,要求正弦信号必须有较高的精度、稳定度及较低的失真率。传统的正弦信号发生器的频率变动由机械驱动可变元件完成,当这种信号发生器用于低频信号输出往往需要的RC值很大,这样不但参数准确度难以保证,而且体积和功耗都很大。而基于单片机技术和D/A转换电路构成的正弦信号发生器就可以解决这些问题。
本文主要介绍了数字式正弦信号发生器的波形产生原理和单片机控制原理。本次设计以单片机技术为基础,通过AT89C51芯片在一定时间内输出一系列的离散数字样点信号,然后通过D/A转换器转换成平滑的正弦波信号,最后通过运算放大器输出。本次设计采用模块化设计的方法,软硬件相结合,硬件设计包括:数码管频率和振幅显示电路、D/A转换正弦信号输出电路、时钟复位电路、键盘频率和振幅输入电路;软件设计包括:显示子程序、D/A转换子程序以及数据计算处理子程序、键盘频率输入子程序。通过软、硬件的结合,既可以实现波形参数的独立连续变化,又具有良好的人机对话界面,原理简单,使用方便。软硬件设计完成后利用KeilμVision2集成开发环境编译该最小系统的程序,利用Proteus仿真软件设计该系统的电路原理图,最后通过两个工具的完美结合对该课题进行系统的软件模拟仿真,结果满足设计要求。本次设计的数字式正弦信号发生器的参数可调,输出波形平滑规则、频率稳定、有较强的实用性。
关键词: 单片机正弦波信号发生器
Design and Realization of Digital Sinusoidal Signal Generator
Abstract
The sine signal is a very extensive application of the signal. the standard sinusoidal signal also beneeded in many tester to detect some physical signal as a standard signal, demanded that sinusoidal signal must have a high accuracy, stability and low distortion rate .The traditional sine signal generator of variable frequency is drived by ponents, when this signal generator used for low frequency signal output often need RC value greatly, It is hard to ensure accuracy parameters,the volume and power based on the single chip puter and D/A transformation of sine signal generator circuit can solve these problems.
This paper mainly introduces the sinusoidal signal generator of digital waveform principle and single-chip puter control principle. Design with micro-controller technology as the foundation, by AT89C51 chip in A certain period of D/A number of discrete output series of converter, then wording point signal converting smooth sine signals, through the operational amplifier output. This design USES modular design method, combining software with hardware design, including: digital tube amplitude and frequency display circuit, D/A transformation sinusoidal output circuit, clocking circuit and reset