Design Of Muti-Waveform Generator Based On FPGA

The development of electronic technology brings more and more difficultrequirement for signal source in testing field and many other fields, in the currentmarket, the high-end waveform generator is very expensive, it’s price is aroundtens of thousand yuan, so developing low-cost and high performance waveformgenerator caused great attention.Direct Digial Frequency Synthesis technology is a full digital and advancedtechnique on frequency synthesis, the waveform generator synthetized on DirectDigital Frequency Synthesis technology has a widest output frequency band, ahigh frequency resolution, a very short frequency switching time, a continuousphase, and it also can generate arbitrary waveform, so it’s developing veryrapidly in recent years.With the improvement of the FPGA working frequency and integration leveland the loss of the cost of FPGA, FPGA technology has been developed rapidly,more and more people begin to pay close attention to use FPGA to complete thedesign of the waveform generator. After a deep research on the Direct DigitalFrequency Synthesis technology, this paper completed the design of waveformgenerator which used MCU as the control center and adopted FPGA as a carrier,this waveform generator can generate superior oblique wave, inferior obliquewave, triangular wave, rectangular wave and trapezoidal wave, the frequencyrange of output waves was1Hz~1MHz and the frequency resolution reached1mHz. In this design, waveform generation process was completed in the internalFPGA, the waveform was not generated by the traditional way of ROM look-uptable, but was produced by sending phase accumulator output to five kinds oflogic gate for transformation, which made the design become more simple and occupy less logic resources. Compared with the waveform generator designed byDDS chip, this waveform generator not only produced more kinds of waveform,but it also was lower cost and more flexible. In addition, FPGA chip supportonline programmable, it made the system have better scalability and betterportability.