【摘要】本文結合作者多年的印制板設計經驗，著重印制板的電氣性能，從印制板穩定性、可靠性方面，來討論多層印制板設計的基本要求。【關鍵詞】印制電路板；表面貼裝器件；高密度互連；通孔【Key words】Printed Circuit Board；Surface Mounting Device；High Density Interface；Via一．概述印制板（PCB－Printed Circuit Board）也叫印制電路板、印刷電路板。多層印制板，就是指兩層以上的印制板，它是由幾層絕緣基板上的連接導線和裝配焊接電子元件用的焊盤組成，既具有導通各層線路，又具有相互間絕緣的作用。隨著SMT（表面安裝技術）的不斷發展，以及新一代SMD（表面安裝器件）的不斷推出，如QFP、QFN、CSP、BGA（特別是MBGA），使電子產品更加智能化、小型化，因而推動了PCB工業技術的重大改革和進步。自1991年IBM公司首先成功開發出高密度多層板（SLC）以來，各國各大集團也相繼開發出各種各樣的高密度互連（HDI）微孔板。這些加工技術的迅猛發展，促使了PCB的設計已逐漸向多層、高密度布線的方向發展。多層印制板以其設計靈活、穩定可靠的電氣性能和優越的經濟性能，現已廣泛應用于電子產品的生產制造中。下面，作者以多年設計印制板的經驗，著重印制板的電氣性能，結合工藝要求，從印制板穩定性、可靠性方面，來談談多層制板設計的基本要領。
上傳時間： 2013-10-08
上傳用戶：zhishenglu
討論、研究高性能覆銅板對它所用的環氧樹脂的性能要求，應是立足整個產業鏈的角度去觀察、分析。特別應從HDI多層板發展對高性能CCL有哪些主要性能需求上著手研究。HDI多層板有哪些發展特點，它的發展趨勢如何——這都是我們所要研究的高性能CCL發展趨勢和重點的基本依據。而HDI多層板的技術發展，又是由它的應用市場——終端電子產品的發展所驅動（見圖1）。 圖1 在HDI多層板產業鏈中各類產品對下游產品的性能需求關系圖 1．HDI多層板發展特點對高性能覆銅板技術進步的影響1.1 HDI多層板的問世，對傳統PCB技術及其基板材料技術是一個嚴峻挑戰20世紀90年代初，出現新一代高密度互連（High Density Interconnection，簡稱為 HDI）印制電路板——積層法多層板（Build—Up Multiplayer printed board，簡稱為 BUM）的最早開發成果。它的問世是全世界幾十年的印制電路板技術發展歷程中的重大事件。積層法多層板即HDI多層板，至今仍是發展HDI的PCB的最好、最普遍的產品形式。在HDI多層板之上，將最新PCB尖端技術體現得淋漓盡致。HDI多層板產品結構具有三大突出的特征：“微孔、細線、薄層化”。其中“微孔”是它的結構特點中核心與靈魂。因此，現又將這類HDI多層板稱作為“微孔板”。HDI多層板已經歷了十幾年的發展歷程，但它在技術上仍充滿著朝氣蓬勃的活力，在市場上仍有著前程廣闊的空間。
上傳時間： 2013-11-19
上傳用戶：zczc
16 relay output channels and 16 isolated digital input channels LED indicators to show activated relays Jumper selectable Form A/Form B-type relay output channel Output status read-back Keep relay output values when hot system reset High-voltage isolation on input channels(2,500 VDC) Hi ESD protection(2,00VDC) High over-voltage protection(70VDC) Wide input range(10~50VDC) Interrupt handling capability High-Density DB-62 connector Board ID
標簽： channels indicators activated isolated
上傳時間： 2016-02-15
上傳用戶：dongbaobao
The Cyclone® III PCI development board provides a hardware platform for developing and prototyping low-power, high-performance, logic-intensive PCI-based designs. The board provides a High-Density of the memory to facilitate the design and development of FPGA designs which need huge memory storage, and also includes Low-Voltage Differential Signaling (LVDS) interface of the High-Speed Terasic Connectors (HSTCs) for extra high-speed interface application.
標簽： development developing prototypi provides
上傳時間： 2017-01-29
上傳用戶：jjj0202
Behavioral models are used in games and computer graphics for realistic simulation of massive crowds. In this paper, we present a GPU based implementation of Reynolds [1987] algorithm for simulating flocks of birds and propose an extension to consider environment self occlusion. We performed several experiments and the results showed that the proposed approach runs up to three times faster than the original algorithm when simulating high density crowds, without compromising significantly the original crowd behavior.
標簽： Behavioral simulation realistic computer
上傳時間： 2017-09-08
上傳用戶：hanli8870
The CommScope InstaPATCH? 360 and ReadyPATCH? solutions utilize a standards-compliant multi-fiber connector to provide high density termination capability. The connector is called an MPO (Multi-fiber Push On) connector by the standards. In many cases, multi-fiber connector products are referred to as MTP connectors. This document is intended to clarify the difference between the two terms – MPO and MTP.
上傳時間： 2017-04-12
上傳用戶：asdfghjkl1234567890
貼片鋁電解電容封裝庫 SMD Aluminum Electrolytic Capacitors VE Features ? 3 ~ 16φ, 85℃, 2,000 hours assured ? Chip type large capacitance capacitors ? Designed for surface mounting on high density PC board. ? RoHS Compliance
上傳時間： 2018-05-09
上傳用戶：angel20041401
The planarization technology of Chemical-Mechanical-Polishing (CMP), used for the manufacturing of multi- level metal interconnects for High-Density Integrated Circuits (IC), is also readily adaptable as an enabling technology in MicroElectroMechanical Systems (MEMS) fabrication, particularly polysilicon surface micromachining. CMP not only eases the design and manufacturability of MEMS devices by eliminating several photolithographic and film issues generated by severe topography, but also enables far greater flexibility with process complexity and associated designs. T
標簽： mechanical polishing Chemical
上傳時間： 2020-06-06
上傳用戶：shancjb
Achieving High Power Density Designs
標簽： Achieving Density Designs Power
上傳時間： 2013-10-12
上傳用戶：qazxsw
資料->【E】光盤論文->【E1】斯坦福博士論文->03 California PhD High integrity GPS-INS filter for precise relative navigation.pdf
標簽： California navigation integrity relative
上傳時間： 2013-07-03
上傳用戶：jiiszha
