基于FPGA与DDS技术的可调超声波驱动电源设计

摘要

To solve the problems existed in the usage of ultrasonic drive power,such as single excitation signal,narrow fre-quency range,and special dedicated,a universal design scheme useing FPGA as the control core of ultrasonic drive power supply was put forward,based on DDS technology,and combining with the advantages of DDS technology and programmable characteristics of FPGA.The designed ultrasonic drive power supply can generate excitation signals of sine wave,triangular wave,square waveand sawtooth wave,and can effectively achieve arbitrary adjustment of frequency within 20 kHz~ 1 MHz through the adjustment of DDS frequency control word.The programmable gain amplifier AD8250 combining with subsection amplification algorithm was used to re-alize the adjustment of power amplification.The simulation results verify that the design of ultrasonic drive power can realize func-tion of optional waveform,adjustable frequency and power,and can effectively drive ultrasonic transducer used in the field of preci-sion measurement.%为解决超声波驱动电源存在激励信号单一、频率范围窄、专机专用等问题，结合DDS技术的优点以及FPGA的可编程性的特点，提出了一种以FPGA为控制核心，基于DDS技术的可以通用的超声波驱动电源的设计方案。设计的超声波驱动电源可以产生正弦波、三角波、方波、锯齿波4种激励信号，并通过对DDS频率控制字的调整可以有效实现频率在20 kHz~1 MHz范围内任意可调，利用可编程增益放大器AD8250结合分段放大算法实现了电源功率的方法与可调。经仿真实验验证设计的超声波驱动电源可以实现波形可选、频率可调、功率可调的功能，能有效驱动应用于超声波精密测量领域的超声波换能器。