Design Of Two-channel 1GSPS Data Acquisition VXI Module

On the base of thorough comprehension of VXI bus specification and high speed data acquisition system, two-channel 1GSPS data acquisition module based on VXIbus is designed in this thesis to implement the real time acquisition and high speed data storage.After analyzing the requirements of the project, the subfunction circuits are compared and argued, and finally the general plan of the module is set down. It is comprised of VXI interface circuit, signal shaping circuit, data acquisition and storage circuit. In the designing of hardware, the high speed A/D converting circuit, high speed data transportation and storage control logic and the method to implement multiple trigger modes are discussed specially. To fulfill the requirement of storage depth and speed, CycloneII FPGA is taken as the control center using pipeline storage technique by connecting pieces of lower speed and cheap RAM to realize high speed and mass capacitance data process. It simplifies the logic control and cuts the hardware cost at the same way. The relative circuit and application of some key devices are described in detail during designing, also with some circuit simulated and tested.PCB design is introduced at the end of the thesis, with some essentials about high speed circuit drawing and reasonable layout to keep its reliability.The module has two high speed data acquisition channels, each with up to 1GSPS real time sampling rate, 8 bits vertical resolution, 4MB data memory deepth, 300MHz analog bandwidth. It has multiple trigger modes and programmable range control. Taking FPGA as the control center, the module combines with high speed data acquirsition, data transform and flexible control all in it.