Research Of Programmable Multi-interface Function Generator Based On DDS

Digital direct frequency synthesis (DDS) is a new frequency synthesis technique at the beginning of 70s in the 20th-Century, its digital structure meets many requirements of modern electronic system, so DDS grows rapidly. With the wide application of Function Generator in modern electronic technology and education fields and the appearance and development of field programmable gate array (FPGA),this article design the Programmable multi-interface Function Generator in which realized DDS in FPGA, the Function Generator can improve the Performance-price Ratio and Reduce Cost.This design realized Programmable multi-interface Function Generator Based on DDS on the combination of hardware and software, this Function Generator can produce sine wave, Square Wave, triangular wave, Saw tooth Wave in any Frequency of 0～40MHz.This design realized the Programmable control of Function Generator on the base of Labview upper computer interface and Various interfaces which are forthcoming Technology in our staff room, and is easy operation。This paper introduced the background, basic principle and characteristics of Direct Digital Frequency Synthesis Technology. Then, based on the theoretical research, this design realized Programmable multi-interface Function Generator Based on DDS. The hardware circuit of this system is divided into several small modules for introduction, including power circuit, display circuit, keyboard, interface boards and so on. Every small module has its corresponding schematic diagram and analysis. Software program is written with C language in Keil C. it can realize swiching over local/remote mode of the instrument, keyboard scan, waveform choice, change of frequency, control of the instrument by receiving data from upper computer and so on. Finally, the joint adjusting of Programmable multi-interface Function Generator includes the connection between debugged instrument and various interface boards,realizing programmable of the instrument by means of Labview upper computer interface.The test results show that the design of Programmable multi-interface Function Generator Based on DDS meets the scheduled requirement. This instrument works reliably, can swich frequency rapidly. It meets the requirements of high frequency, High Stability, and High Resolution, also it has characters of high cost performance and low price,it can introduce waveform whose frequency is up to 40MHz。...