高采样频率位移测量系统硬件架构设计

Design of hardware architecture of displacement measurement system with high sampling frequency

在高端光刻机中,光栅尺掩模台位移测量系统拥有较复杂的运算模型,而且要求测量系统硬件架构能满足20 kHz高采样频率的需求。通过对国内运动台位移测量系统硬件架构进行对比研究,提出一种兼容以往软件架构的基于多核DSP运算板卡的光栅尺掩模台位移测量系统硬件架构,使用多核DSP内核间共享内存通信的机制,取代运算板卡间数据总线通信的机制,同时由板内PCIe总线互联片上多核DSP与FPGA。搭建硬件在环仿真平台进行实验,实验结果表明,系统获取原始数据、进行模型运算以及发送位置数据的总体性能提升百分比约为136%,保证模型运算精度的同时,满足20 kHz采样频率的要求。

In the high-end lithography machine,the displacement measurement system of the grating scale reticle stage has complex operation model,and the hardware architecture of the measurement system is required to meet the requirement of high sampling frequency of 20 kHz.With the comparison study of the hardware architecture of the displacement measurement system of the motion platform in China,a hardware architecture of the grating scale reticle stage displacement measurement system based on the multi-core DSP operation board card is proposed,which is compatible with the previous software architecture.The mechanism of shared memory communication among multi-core DSP cores is used to replace the mechanism of data bus communication among operation board cards,and the interconnection of on-chip multi-core DSP and FPGA is performed through on-board PCI bus.A hardware-in-loop simulation platform was built to carry out the experiment.The experimental results show that the overall performance improvement percentage of the system in the aspects of raw data acquisition,model operation and location data sending is about 136%,which ensures the accuracy of the model operation and meets the requirement of sampling frequency of 20 kHz.