基于MicroBlaze软核的任意波形发生器设计

Design of Arbitrary Waveform Generator Based on Microblaze Embedded Soft Core

本设计利用FPGA的高速和可重构性,在VIVADO开发平台下,将MicroBlaze软核以及DDS模块嵌入到FPGA芯片上,与LCD触摸屏、D/A转换器、低通滤波器和幅度控制放大器等构成系统的硬件电路。通过对在LCD触摸屏上手动绘制的任意图形进行采样,得到所需的图形数据,再对该图形数据进行插值处理,得到手绘任意波的波形数据,并存入DDS波形存储器,然后再利用DDS相位累加器,读出波形数据,经过数模转换、滤波从而得到手绘的任意波形信号。该系统不仅能产生正弦波、方波、三角波,也能产生幅度和频率可调的任意波,具有频率范围宽、频率分辨率高、频率切换速度快等特点。

This design utilizes the high-speed and reconfigurable FPGA. In the VIVADO development platform, MicroBlaze soft core and DDS module are embedded in the FPGA chip. The hardware circuit of the system is composed of FPGA, LCD touch screen, D/A converter, low-pass filter and amplitude control amplifier. By sampling any graphics manually drawn on the LCD touch screen, the required graphics data are obtained. After interpolating the graph data, the waveform data of any hand-drawn wave can be obtained and stored in the DDS waveform memory. Then, the waveform data are read out by using the DDS phase accumulator, and the hand-drawn arbitrary waveform signal is obtained through digital-to-analog conversion and filtering. The system can produce sine wave, square wave, triangle wave and arbitrary wave with adjustable amplitude and frequency. It has the characteristics of wide frequency range, high frequency resolution and fast frequency switching.