| The aim of this graduate design is to design a Digital Save Oscillograph (DSO) based on the USB interface technology. It is not only a virtual test instrument,but also a peripheral of computers. Together with computers,the instrument can construct a powerful test system.In order to realize the functions of this system,the advanced sampling technology-under sampling technology,is used in the digital sampling module. The delay chip,whose delay precision can be 10ps,wide band sample-hold amplifier (SHA),and high speed and precise analog/digital conversion (ADC) are used in the system. In the control module,making good use of the powerful function of singlechip machine (SCM) and the flexibility and the high speed of programmable logic devices (PLD) to realize the capability and the efficiency of control. In the module of interface with computers,USB interface technology is used to realize the plug and play (PnP) and high data transfer rate. USB interface is a capable interface technology,which is widely used for the peripheral of computers. In the module of wave shape display and data analysis in computers,Lab Windows CVI ,which is the product of NI corporation special for the virtual instrument,is used as the software develop plat to realize the character of powerful,humanistic and convenient.The digital save oscillograph based on USB interface designed has the characters of convenient and flexibility. It can be connected to computers with PnP. The signal wave is displayed clearly on the screen of the computers and the analysis of the data is precise. It can sample the random signal with the frequency wide under 5MHz and display the signal waveform. As far as the cycle signal with the frequency under 10MHz is concerned,the instrument can sample it with under sampling and analyze the frequency character. It can also save and share the data sampled from the signal. |
PDF Full Text Request