基于SDIO与SPI接口的信号发生器

摘要

为了解决传统DDS信号发生器的输出波形种类少、幅频控制精度低等缺点，设计了基于SDIO与SPI接口的高精度信号发生器。首先，采用STM32F103作为核心控制器，SDIO接口作为用户波形数据交互口。其次，采用SPI接口将数据传送至WAV数据流解码芯片VS1053，解码后18位D／A输出。然后，采用程控放大器对输出波形进行幅值控制。最后，采用功率放大器进行功率放大。相比于传统信号发生器，可实现任意波形输出，且幅频可控。%In order to overcome the problem that the frequency and amplitude of the traditional signal generator of direct digital frequency synthesizer( DDS) is hard to control,a new signal generator based on SDIO and SPI interface was introduced.Firstly, STM32F103 was as its MCU, and data acquisition was through SDIO interface.Secondly, waveform data were sent to decoder VS1053 through SPI bus,and 16 bits analog data came out.Lastly,power and programmable gain amplifier was used to control fre-quency and amplitude.This new signal generator has the advantages that the output is random waveform and the amplitude-frequen-cy can be controlled.