A new type of cloak is discussed: one that gives all cloaked objects the appearance of a flat conducting
sheet. It has the advantage that none of the parameters of the cloak is singular and can in fact be made
isotropic. It makes broadband cloaking in the optical frequencies one step closer.
Most circuit designers are familiar with diode dynamiccharacteristics such as charge storage, voltage dependentcapacitance and reverse recovery time. Less commonlyacknowledged and manufacturer specifi ed is diode forwardturn-on time. This parameter describes the timerequired for a diode to turn on and clamp at its forwardvoltage drop. Historically, this extremely short time, unitsof nanoseconds, has been so small that user and vendoralike have essentially ignored it. It is rarely discussed andalmost never specifi ed. Recently, switching regulator clockrate and transition time have become faster, making diodeturn-on time a critical issue. Increased clock rates aremandated to achieve smaller magnetics size; decreasedtransition times somewhat aid overall effi ciency but areprincipally needed to minimize IC heat rise. At clock speedsbeyond about 1MHz, transition time losses are the primarysource of die heating.
A tutorial on SAR type A/D converters, this note contains detailed information on several 12-bit circuits. Comparator, clocking, and preamplifier designs are discussed. A final circuit gives a 12-bit conversion in 1.8µs. Appended sections explain the basic SAR technique and explore D/A considerations.
Highlights the LTC1062 as a lowpass filter in a phase lock loop. Describes how the loop's bandwidth can be increased and the VCO output jitter reduced when the LTC1062 is the loop filter. Compares it with a passive RC loop filter. Also discussed is the use of LTC1062 as simple bandpass and bandstop filter.
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.
AN22 details the theoretical and application aspects of the LT1088 thermal RMS/DC converter. The basic theory behind thermal RMS/DC conversion is discussed and design details of the LT1088 are presented. Circuitry for RMS/DC converters, wideband input buffers and heater protection is shown.
介紹基于ISA總線與KH-9300的數(shù)據(jù)采集板卡的設(shè)置，詳細(xì)說明8254定時計數(shù)器及8259中斷控制器的結(jié)構(gòu)特點、工作方式、控制字等，探討中斷類型、中斷處理程序、中斷矢量表及其填寫。重點講述使用TorboC編寫中斷服務(wù)程序的方法，應(yīng)注意的主要問題及程序測試的結(jié)果。
Abstract:
The settings of KH-9300 data acquisition board based on the ISA bus is introduced,the structural characteristics,working methods,control characters of the timing counter 8254 and interruptioncontroller 8259 are explained in detail.The interruption type,interrupt handling programs,interruption vector table and its filling also are discussed.Further,great emphasis is put on the method of interrupt service program compiled by Torbo C,the main issues that should be noted,and the results of program testing.
介紹一種基于C8051F060單片機和NAND Flash的數(shù)據(jù)采集存儲系統(tǒng)，該系統(tǒng)可實現(xiàn)3路信號采樣，每路采樣率為5KS/s,通過異步串行通信接口實現(xiàn)數(shù)據(jù)傳輸。并詳細(xì)說明系統(tǒng)的軟件設(shè)計。
Abstract:
An acquisition and storage system based on C8051F060and NAND Flash is designed in this paper.The system is used to sample three-channel of signal,5KSPS each channel,and can upload data to test bench through UART（Universal Asynchronous Receiver/Transmitter）.The software design is discussed in detail.
