基于PCI总线,FPGA和DDS原理的特点,设计了具有高精度、高稳定性及高准确性的多通道模拟信号源系统;系统采用以FPGA为主控单元,通过PCI总线接受上位机传输的指令来控制其内部ROM的读写、14位高精度D/A转换器AD9744的转换和多路选择开关ADG1208的选通,产生多路模拟信号输出,并且频率精确度达到0.01%,符合设计要求。
the system of multi channel analog signals source with high accuracy, high stability and high accuracy has been designed based on the PCI bus, FPGA and principle of DDS. The system adopts FPGA as the main control unit, accepts instructions of PC through the PCI bus to control reading and writing to the internal ROM of FPGA, conversion of 14 high precision D / A device AD9744 and gating of multi-channel selector switch ADG1208, produces multi-channel analog signal output and accuracy frequency reaches 0. 01%, and the system meets requirements of design.