Photodiodes can be broken into two categories: largearea photodiodes with their attendant high capacitance(30pF to 3000pF) and smaller area photodiodes withrelatively low capacitance (10pF or less). For optimalsignal-to-noise performance, a transimpedance amplifi erconsisting of an inverting op amp and a feedback resistoris most commonly used to convert the photodiode currentinto voltage. In low noise amplifi er design, large areaphotodiode amplifi ers require More attention to reducingop amp input voltage noise, while small area photodiodeamplifi ers require More attention to reducing op amp inputcurrent noise and parasitic capacitances.
上传时间： 2013-10-28
上传用户：hanbeidang
This application note features 8-, 10-, and 12-bit dataacquisition components in various circuit configurations.The circuits include battery monitoring, temperature sensing,isolated serial interfaces, and microprocessor andmicrocontroller serial and parallel interfaces. Also includedare voltage reference circuits (Application Note 42contains More voltage reference circuits).
上传时间： 2014-01-15
上传用户：zq70996813
The Reactor design pattern handles service requests that are delivered concurrently to an application by one or More clients. Each service in an application may consist of serveral methods and is represented by a separate event handler that is responsible for dispatching service-specific requests.
上传时间： 2013-10-15
上传用户：libinxny
A complete design for a data acquisition card for the IBM PC is detailed in this application note. Additionally, C language code is provided to allow sampling of data at speed of More than 20kHz. The speed limitation is strictly based on the execution speed of the "C" data acquisition loop. A "Turbo" XT can acquire data at speeds greater than 20kHz. Machines with 80286 and 80386 processors can go faster than 20kHz. The computer that was used as a test bed in this application was an XT running at 4.77MHz and therefore all system timing and acquisition time measurements are based on a 4.77MHz clock speed.
上传时间： 2013-10-29
上传用户：BOBOniu
Radio Frequency Integrated Circuit Design I enjoyed reading this book for a number of reasons. One reason is that itaddresses high-speed analog design in the context of microwave issues. This isan advanced-level book, which should follow courses in basic circuits andtransmission lines. Most analog integrated circuit designers in the past workedon applications at low enough frequency that microwave issues did not arise.As a consequence, they were adept at lumped parameter circuits and often notcomfortable with circuits where waves travel in space. However, in order todesign radio frequency (RF) communications integrated circuits (IC) in thegigahertz range, one must deal with transmission lines at chip interfaces andwhere interconnections on chip are far apart. Also, impedance matching isaddressed, which is a topic that arises most often in microwave circuits. In mycareer, there has been a gap in comprehension between analog low-frequencydesigners and microwave designers. Often, similar issues were dealt with in twodifferent languages. Although this book is More firmly based in lumped-elementanalog circuit design, it is nice to see that microwave knowledge is brought inwhere necessary.Too many analog circuit books in the past have concentrated first on thecircuit side rather than on basic theory behind their application in communications.The circuits usually used have evolved through experience, without asatisfying intellectual theme in describing them. Why a given circuit works bestcan be subtle, and often these circuits are chosen only through experience. Forthis reason, I am happy that the book begins first with topics that require anintellectual approach—noise, linearity and filtering, and technology issues. Iam particularly happy with how linearity is introduced (power series). In therest of the book it is then shown, with specific circuits and numerical examples,how linearity and noise issues arise.
上传时间： 2014-12-23
上传用户：han_zh
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： 2013-10-14
上传用户：ysystc699
This document provides practical, common guidelines for incorporating PCI Express interconnect layouts onto Printed Circuit Boards (PCB) ranging from 4-layer desktop baseboard designs to 10- layer or More server baseboard designs. Guidelines and constraints in this document are intended for use on both baseboard and add-in card PCB designs. This includes interconnects between PCI Express devices located on the same baseboard (chip-to-chip routing) and interconnects between a PCI Express device located “down” on the baseboard and a device located “up” on an add-in card attached through a connector. This document is intended to cover all major components of the physical interconnect including design guidelines for the PCB traces, vias and AC coupling capacitors, as well as add-in card edge-finger and connector considerations. The intent of the guidelines and examples is to help ensure that good high-speed signal design practices are used and that the timing/jitter and loss/attenuation budgets can also be met from end-to-end across the PCI Express interconnect. However, while general physical guidelines and suggestions are given, they may not necessarily guarantee adequate performance of the interconnect for all layouts and implementations. Therefore, designers should consider modeling and simulation of the interconnect in order to ensure compliance to all applicable specifications. The document is composed of two main sections. The first section provides an overview of general topology and interconnect guidelines. The second section concentrates on physical layout constraints where bulleted items at the beginning of a topic highlight important constraints, while the narrative that follows offers additional insight.
上传时间： 2013-10-15
上传用户：busterman
A light-emitting diode (LED) is a semiconductor device that emits narrow-spectrum incoherent light when forward-biased.The color of the emitted light depends on the chemical composition of the semiconductor material used, and can benear-ultraviolet, visible or infrared. LEDs are More prevalent today than ever before, replacing traditional incandescent andfluorescent bulbs in many lighting applications. Incandescents use a heated filament, are subject to breakage and burnoutand operate at a luminous efficiency of 2% to 4%. Fluorescents are More efficient, at 7% to 12%, but require highdrive voltage and contain mercury, a toxic substance that may be eventually banned in certain countries. LEDs, however,produce light directly through electroluminescence, operate at low voltage and can deliver over 20% luminous efficiency.
上传时间： 2013-11-07
上传用户：xiaoyuer
Abstract: Investment in smart meters and smart grid end equipment continues to grow worldwide as countriestry to make their electric delivery systems More efficient. However, as critical as the electric deliveryinfrastructure is, it is normally not secured and thus subject to attack. This article describes the concept oflife-cycle security—the idea that embedded equipment in the smart grid must have security designed into theentire life of the product, even back to the contract manufacturer. We also talk about how life-cycle securityapplies to embedded equipment in the smart grid. Potential threats are discussed, as are potential solutionsto mitigate the risks posed by those threats.
上传时间： 2014-12-24
上传用户：熊少锋
Abstract: Some types of loads require More current during startup than when running. Other loads can be limited to a lower-powercurrent during startup but require a higher operating current. This article describes an application circuit that automatically adjusts apower circuit’s overcurrent protection level up or down after startup is complete.
上传时间： 2013-10-23
上传用户：swaylong
