Usb Interface Data Acquisition System For Solar Cell Testing

The paper develops the data acquisition board with USB interface which is used in the testing equipment of photovoltaic cell/module. This design adopts USB interface chip, FPGA chip, high-speed and high-precision A/D converter, low-speed and high-precision A/D converter, MCU and so on, to develop a data acquisition board with USB interface used in the testing of photovoltaic. low cost, convenience using, high interference immunity; enhancing test precision, convenience of ISP.At first, this thesis introduces the general structure of the photovoltaic test equipment and the data acquisition board with USB interface that is part of the photovoltaic test equipment. After that, this paper introduces the hardware and software design of the data acquisition board with USB interface.In the hardware circuit design section of this thesis, we give the general design structure of the hardware circuit, including the high speed data acquisition unit, the low speed data acquisition unit, MCU, the USB interface component, the power supply circuit of system and the FPGA configuration circuit. Then we detaildedly introduce the components' characters and the design method of all parts of circuits.The software design of this thesis includes the VHDL programming to realize the function of FPGA and the MCU firmware programming. The system uses the hardware description language(VHDL) and top-down methods, and realizes every logic function module. Finally, the FPGA function is achieved by schematic document; In addition, this paper detaildedly introduces the MCU firmware programming, including USB firmware program, main program, data acquisition program. Furthermore, the Flow Diagrams of the program of each part of the MCU firmware programming are drawn in this chapter.