基于TMS320DM6446棉花检测硬件系统设计

【作者】 李浩；

【导师】 沙涛；

【作者基本信息】 南京理工大学 ， 电路与系统， 2010， 硕士

【摘要】 棉花异性纤维检测在整个棉纺工业生产中占据重要地位。棉花中的异性纤维对生产出的棉花质量影响非常大,如果没有对其进行分拣清除,将严重影响相关棉纺产品的质量,从而影响到整个棉纺工业的利益。根据目前的技术研究现状,本文基于数字图像处理技术在工业检测领域中的应用,结合棉花检测系统对于低成本、高智能性的需求,采用了基于TI高性能DSP双核芯片TMS320DM6446的棉花检测系统硬件设计方案。本系统属于典型的高速电路,因此在系统PCB的设计过程中,我们不得不面对高速互连设计中的反射、串扰、阻尼振荡以及系统互连延迟引起的时序等一系列信号完整性(Signal Integrity,简称SI)问题。解决好信号完整性问题,是系统设计成功的关键。本文借助功能强大的Cadence软件,在设计前对高速信号线进行信号完整性分析,然后根据仿真结果制定约束规则,减小信号完整性现象的影响程度。实践证明信号完整性设计缩短了设计周期,具有比较好的理论和实际意义。本文首先结合系统功能需求分析了其性能指标,围绕选定的DSP核心处理器,完成棉花检测硬件系统的原理图设计,包括最小硬件系统设计、视频接口设计和通信接口设计；接着讨论了系统中有可能出现的信号完整性问题,并确定本系统中的关键高速信号网络。基于信号完整性理论,利用Cadence软件的SPECCTRAQuest仿真工具对关键网络进行了仿真与分析,并采取措施抑制了可能出现的信号完整性现象,结合仿真结果得出一系列PCB设计所需的约束规则条件；最后利用Cadence软件中的Allegro工具进行PCB设计,布线前添加仿真得出的约束条件,并根据约束条件完成PCB布线,布线后又利用SPECCTRAQuest工具进行了后仿真工作,验证系统满足信号完整性要求,最终完成棉花检测硬件系统的PCB设计。更多还原

【Abstract】 Detection of foreign fibers production throughout the cotton industry occupies an important position. Cotton impurities on the quality of cotton produced great influence; if not to sort their removal would seriously affect the quality of products related to cotton, thus affecting the interests of the entire cotton industry. Under the current technology, this paper based on digital image processing technology in the field of industrial inspection applications, combined with cotton detection system for low-cost, high-demand intelligence, a high-performance DSP based on TI dual-core chips TMS320DM6446 cotton testing system hardware design.This system is typical of high-speed circuit, the PCB design process in the system, we have to face high-speed interconnect design reflection, crosstalk, damped oscillations and the system interconnect timing delay caused by a series of signal integrity (Signal Integrity, called SI) issues. Solve the signal integrity issue is the system the key to success. With the help of powerful Cadence software design before the high-speed signal lines for signal integrity analysis, and constraint rules formulated according to the simulation results, reducing the influence of the phenomenon of signal integrity. Signal Integrity Design proved to shorten the design cycle, with good theoretical and practical significance.This combination of system functional requirements of the first analysis of its performance around the selected DSP processors, the completion of the cotton test schematic design of the hardware system, including the minimum hardware system design, video interface and communication interface; went on to discuss the system possible signal integrity issues, and to determine the system’s key high-speed signaling network. Theory based on signal integrity, simulation using Cadence software tools SPECCTRAQuest critical network simulation and analysis, and to take measures to curb the phenomenon of possible signal integrity, combined with simulation results obtained the required number of PCB design constraints rule conditions; Finally, use Cadence Allegro tools for PCB design, added the simulation shows before routing, and completed PCB layout under the constraints, after routing using SPECCTRAQuest tools of simulation work to verify the system requirements to meet the signal integrity.Complete the cotton test PCB hardware system design.更多还原