Design Of Signal Generator Based On FPGA Technology

The signal generator is an excitation source in the electronic measurement. In field of electronic engineers, production line, teaching and research, electronic testing, electronic design, simulation, the signal generator has played a huge role as an important test equipment, greatly enhances human work efficiency, and thus has been drawn a number of researchers attention to. Its theory and design was conducted in-depth research by researchers, and had been made progress greatly. At present, the way of the direct digital frequency synthesis is the most advanced theoretical method of the design of the source generator. Based on the basic principle of the direct digital frequency synthesis and FPGA technology, the system was designed as four-channel multi-function signal sources. It can not only launch the basic waveform, but also according to user requirements can define arbitrary waveform.Firstly, the development of the signal generator, and the current status of development of test equipment such as signal generator and the problems at home were introduced in this paper. Secondly, the basic theory of design knowledge of the signal generator was described. And then according to main parameters index and performance requirements of the signal generator system, the overall design of the system was completed.In this paper, the principles of the various key chips selection and the hardware design and implementation of the multifunction signal generator system were shown. The design of the systemic hardware is basic of the system. The part of systemic hardware mainly included the main channel of DDS module, the signal processing circuit, the data collecting circuit, the data control module circuit and other parts. The main channel of DDS module was designed implemented by the FPGA and SRAM. The signal processing circuit was mainly made up of the D/A converter circuit, the low-pass filter circuit, the gain control circuit and the buffer circuit. The data collecting circuit was mainly composed of FPGA and the A/D converter circuit. And the data control module was achieved by the MSP430F1611 microcontroller that controlled reading CF card and the touch-screen transmission parameters.The part of software in the signal generator system was also designed, and combining with hardware design, the overall system functionality had been implemented. The software design included FPGA software design and the MSP430F1611 microcontroller software design. And we discussed some software design in detail, which the main channel of DDS module was achieved by FPGA software, and MCU read the procedures of CF card.Finally, the hardware debugging and software debugging of the system were discussed in detail, and the overall system functionality had been achieved.