ExpressPCB 是一款免费的PCB设计软件，简单实使。可以画双层板。 Our Free PCB software is a snap to learn and use. For the first time, designing circuit boards is simple for the beginner and efficient for the professional. Our board manufacturing service makes top quality two and four layer PCBs. Use our MiniBoard service and pay only $51 for three boards (plus $8 shipping).
标签： ExpressPCB PCB 设计软件
上传时间： 2013-11-15
上传用户：lchjng
基本的编辑工具(GENERAL EDITING FACILITIES) 对象放置(Object Placement) ISIS支持多种类型的对象，每一类型对象的具体作用和功能将在下一章给出。虽然类型不同，但放置对象的基本步骤都是一样的。 放置对象的步骤如下(To place an object:) 1.根据对象的类别在工具箱选择相应模式的图标(mode icon)。 2. Select the sub-mode icon for the specific type of object. 2、根据对象的具体类型选择子模式图标(sub-mode icon)。 3、如果对象类型是元件、端点、管脚、图形、符号或标记，从选择器里(selector)选择你想要的对象的名字。对于元件、端点、管脚和符号，可能首先需要从库中调出。 4、如果对象是有方向的，将会在预览窗口显示出来，你可以通过点击旋转和镜象图标来调整对象的朝向。 5、最后，指向编辑窗口并点击鼠标左键放置对象。对于不同的对象，确切的步骤可能略有不同，但你会发现和其它的图形编辑软件是类似的，而且很直观。 选中对象(Tagging an Object) 用鼠标指向对象并点击右键可以选中该对象。该操作选中对象并使其高亮显示，然后可以进行编辑。
上传时间： 2013-10-29
上传用户：avensy
superpro 3000u 驱动 PIC16C65B@QFP44 [SA245] PIC16C65B: Part number QFP44: Package in QFP44 SA245: Adapter purchase number AM29DL320GT@FBGA48 [SA642+B026] AM29DL320GT: Part number FBGA48: Package in FBGA48 SA642: Adapter purchase number (Top board with socket) B026: Adapter purchase number (Bottom board, exchangable for different parts) 87C196CA@PLCC68(universal adapter) [PEP+S414T] 87C196CA: Part number PLCC68: Package in PLCC68 universal adapter: this adapter is valid for all parts in this package PEP: The PEP (Pin-driver Expansion Pack necessary to work with the adapter S414T) S414T: Adapter purchase number (Universal for all parts in this package) S71PL127J80B@FBGA64(special adapter) [(SA642A-B079A-Y096AF001)] S71PL127J80B: Part number FBGA64: Package in FBGA64 special adapter: this adapter is valid for this
上传时间： 2013-10-23
上传用户：Avoid98
ExpressPCB 是一款免费的PCB设计软件，简单实使。可以画双层板。 Our Free PCB software is a snap to learn and use. For the first time, designing circuit boards is simple for the beginner and efficient for the professional. Our board manufacturing service makes top quality two and four layer PCBs. Use our MiniBoard service and pay only $51 for three boards (plus $8 shipping).
标签： ExpressPCB PCB 设计软件
上传时间： 2013-10-09
上传用户：1047385479
Abstract: Using a wafer-level package (WLP) can reduce the overall size and cost of your solution.However when using a WLP IC, the printed circuit board (PCB) layout can become more complex and, ifnot carefully planned, result in an unreliable design. This article presents some PCB designconsiderations and general recommendations for choosing a 0.4mm- or 0.5mm-pitch WLP for yourapplication.
标签： Considerations Guidelines and Design
上传时间： 2013-11-09
上传用户：ls530720646
This white paper discusses how market trends, the need for increased productivity, and new legislation have accelerated the use of safety systems in industrial machinery. This TÜV-qualified FPGA design methodology is changing the paradigms of safety designs and will greatly reduce development effort, system complexity, and time to market. This allows FPGA users to design their own customized safety controllers and provides a significant competitive advantage over traditional microcontroller or ASIC-based designs. Introduction The basic motivation of deploying functional safety systems is to ensure safe operation as well as safe behavior in cases of failure. Examples of functional safety systems include train brakes, proximity sensors for hazardous areas around machines such as fast-moving robots, and distributed control systems in process automation equipment such as those used in petrochemical plants. The International Electrotechnical Commission’s standard, IEC 61508: “Functional safety of electrical/electronic/programmable electronic safety-related systems,” is understood as the standard for designing safety systems for electrical, electronic, and programmable electronic (E/E/PE) equipment. This standard was developed in the mid-1980s and has been revised several times to cover the technical advances in various industries. In addition, derivative standards have been developed for specific markets and applications that prescribe the particular requirements on functional safety systems in these industry applications. Example applications include process automation (IEC 61511), machine automation (IEC 62061), transportation (railway EN 50128), medical (IEC 62304), automotive (ISO 26262), power generation, distribution, and transportation. 图Figure 1. Local Safety System
上传时间： 2013-11-14
上传用户：zoudejile
使用Nios II软件构建工具 This chapter describes the Nios® II Software Build Tools (SBT), a set of utilities and scripts that creates and builds embedded C/C++ application projects, user library projects, and board support packages (BSPs). The Nios II SBT supports a repeatable, scriptable, and archivable process for creating your software product. You can invoke the Nios II SBT through either of the following user interfaces: ■ The Eclipse™ GUI ■ The Nios II Command Shell The purpose of this chapter is to make you familiar with the internal functionality of the Nios II SBT, independent of the user interface employed.
上传时间： 2013-10-12
上传用户：china97wan
Introduction to Xilinx Packaging Electronic packages are interconnectable housings for semiconductor devices. The major functions of the electronic packages are to provide electrical interconnections between the IC and the board and to efficiently remove heat generated by the device. Feature sizes are constantly shrinking, resulting in increased number of transistors being packed into the device. Today's submicron technology is also enabling large-scale functional integration and system-on-a-chip solutions. In order to keep pace with these new advancements in silicon technologies, semiconductor packages have also evolved to provide improved device functionality and performance. Feature size at the device level is driving package feature sizes down to the design rules of the early transistors. To meet these demands, electronic packages must be flexible to address high pin counts, reduced pitch and form factor requirements. At the same time,packages must be reliable and cost effective.
上传时间： 2013-11-21
上传用户：不懂夜的黑
This application note shows how to achieve low-cost, efficient serial configuration for Spartan FPGA designs. The approachrecommended here takes advantage of unused resources in a design, thereby reducing the cost, part count, memory size,and board space associated with the serial configuration circuitry. As a result, neither processor nor PROM needs to be fullydedicated to performing Spartan configuration.In particular, information is provided on how the idle processing time of an on-board controller can be used to loadconfiguration data from an off-board source. As a result, it is possible to upgrade a Spartan design in the field by sending thebitstream over a network.
上传时间： 2013-11-01
上传用户：wojiaohs
Today’s digital systems combine a myriad of chips with different voltage configurations.Designers must interface 2.5V processors with 3.3V memories—both RAM and ROM—as wellas 5V buses and multiple peripheral chips. Each chip has specific power supply needs. CPLDsare ideal for handling the multi-voltage interfacing, but do require forethought to ensure correctoperation.
上传时间： 2013-11-10
上传用户：yy_cn
