Design of four-channel high precision data acquisition system with USB interface

The design of data acquisition system with high speed and high precision,which is based on USB (Universal Serial Bus),is introduced in this paper. A new audio A/D chip AKM5394 is applied to the data acquisition system. Using CPLD,FIFO,USB interface chip and two AKM5394,a four channel data acquisition system with high precision is implemented. The data are also saved and displayed in real time by USB interface on computer. The driving program,which is used for Windows 2000 or Windows XP,and the application program of the system are realized in Visual C++ language,and the firmware codes are programmed in C language. Because of low cost and a high performance,the system with a measuring precision up to 22 bit can be widely used in such fields as measuring control,signal analysis,and so on.