Research On Signal Generator And Acquisitions System Based On USB Interface

With the development of modern industry production and science research, the signal generator and data acquisition face new challenges. The conventional signal generator can't satisfy the need of variety of waveform and the higher precision of signal. Universal Serial Bus is one of interfaces of personal computer, which is high-speed, convenient and low-cost. To a great extent, it can improve conflicts between the interface and peripheral equipments. Thereby in recent years, it is used in more and more extensive applications. The USB2.0 interface supports signaling at two speeds: full-speed signaling at 12.0Mbps and high-speed signaling at 480Mbps. In many high tests, we need data acquisition system with high-speed. It has important meaning to reseach USB interface as the interface between data system and personal computer.The paper researches new signal generator and high-speed data acquisition system based on USB2.0 interface. We choose the chip AD9954 as core of the signal generator. The AD9954 is a direct digital synthesizer (DDS) featuring a 14-bit DAC operating up to 400 MSPS. The AD9954 uses advanced DDS technology, coupled with an internal high speed, high performance DAC to form a digitally programmable, complete high frequency synthesizer capable of generating a frequency-agile analog output sinusoidal waveform at up to 200 MHz. The frequency preision of output signal is up to 6mHz. We choose the chip of AD9214 as core of data acquisition. The AD9214 is easy to control.There are some contents are presented as follows: researching how to use USB2.0 interface to signal generator and high-speed data acquisition system; programming firmware of EZ-USB FX2 of Cypress Company and application based on PC; designing circuits of the high speed data acquisition and the signal generator. At last, it explains how to debug the program and circuits and get the results.The paper designs and realizes the new signal generator and high speed data acquisition system based on USB2.0 interface, and the whole system have been verified in application.