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。
本文主要介绍了正弦波波形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STC89C52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：D/A转换正弦信号输出电路、时钟复位电路；软件设计包括： D/A转换程序以及数据计算处理程序。软硬件设计完成后利用KeilμVision2集成开发环境编译该系统的程序，利用Proteus仿真软件设计该系统的电路原理图，然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，依据正确的仿真结果设计好电路板并进行电路板元器件的焊接，布线的工作，最后再对系统总体功能进行调试，在示波器上显示出正弦波形。本次设计的正弦波波形发生器的参数可调，输出波形平滑规则、频率稳定、有较强的实用性。
关键词：正弦波波形发生器；DAC0832；单片机；正弦波
Abstract: Sine ac signal is a very extensive application of the signal. In many tester using standard need in the sine signal detection some physical quantities. Sine signals used as standard signal, sine signal requirements must be more precision, stability and low distortion rate. The traditional sine signal generator frequency change by mechanical driving variable components to complete, when this signal generator used for low frequency signal output often need RC value is very big, such not only hard to ensure accuracy parameters, and volume and power consumption are very big. And based on single chip microcomputer technology and D/A transformation circuit consists of the sine signal generator can solve these problems.
This article mainly introduced the sine wave generator waveform principle and single-chip microcomputer control principle. The design on the single chip computer technology as the foundation, through the STC89C52 chip in a certain time output a series of discrete number "point signal, and then through the D/A converter converted into smooth sine signals, the last through the operational amplifier output. This design USES modular design method, combining software, hardware design including: D/A transformation sine signal output circuit, clocking reset circuit; The software design including: D/A conversion program and data processing program. After the completion of the hardware and software design using Keil μ Vision2 integrated development environment compile the system program, using the Proteus simulation software design the system of the circuit principle diagram, and then through the two tools for the perfect combination of the subject system software simulation, according to accurate simulation results of good circuit board design and circuit board components of welding, cabling work, and finally to the overall function of the system, debugging in oscilloscope showed on the sine wave. The design of the sine wave of the parameters of the waveform generator can be adjusted, the output waveform rules, frequency stability, smooth has good practicability.
Key words：Sine wave generator；DAC0832；SCM；Sine wave
