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
长电c2383 TO-92L
上传时间： 2013-11-09
上传用户：wvbxj
高的工作电压高达100V N双N沟道MOSFET同步驱动 The D810DCDC is a synchronous step-down switching regulator controller that can directly step-down voltages from up to 100V, making it ideal for telecom and automotive applications. The D810DCDC uses a constant on-time valley current control architecture to deliver very low duty cycles with accurate cycle-by-cycle current limit, without requiring a sense resistor. A precise internal reference provides 0.5% DC accuracy. A high bandwidth (25MHz) error amplifi er provides very fast line and load transient response. Large 1Ω gate drivers allow the D810DCDC to drive multiple MOSFETs for higher current applications. The operating frequency is selected by an external resistor and is compensated for variations in VIN and can also be synchronized to an external clock for switching-noise sensitive applications. Integrated bias control generates gate drive power from the input supply during start-up and when an output shortcircuit occurs, with the addition of a small external SOT23 MOSFET. When in regulation, power is derived from the output for higher effi ciency.
上传时间： 2013-10-24
上传用户：wd450412225
Alkaline batteries are convenient because they’re easy tofi nd and relatively inexpensive, making them the powersource of choice for portable instruments and devicesused for outdoor recreation. Their long shelf life alsomakes them an excellent choice for emergency equipmentthat may see infrequent use but must be ready to go on amoment’s notice. It is important that the DC/DC convertersin portable devices operate over the widest possiblebattery voltage range to extend battery run time, and thussave the user from frequent battery replacement.
上传时间： 2014-12-24
上传用户：569342831
The LTC®4155 and LTC4156 are dual multiplexed-inputbattery chargers with PowerPath™ control, featuring I2Cprogrammability and USB On-The-Go for systems suchas tablet PCs and other high power density applications.The LTC4155’s float voltage (VFLOAT) range is optimizedfor Li-Ion batteries, while the LTC4156 is optimized forlithium iron phosphate (LiFePO4)batteries, supportingsystem loads to 4A with up to 3.5A of battery chargecurrent. I2C controls a broad range of functions and USBOn-The-Go functionality is controlled directly from theUSB connector ID pin.
上传时间： 2013-10-09
上传用户：hanhanj
毕业设计 USB TO Gigabit LAN 网卡 随着网络技术飞速发展，多媒体的应用越来越多，人们对网络的要求也越来越高，为了适应市场的需求，网卡出现了。它以其结构简单、成本低廉、兼容性强等诸多的优越性得到了广泛的应用。由于网络的应用越来越广泛，网卡的应用也越来越多、功能越来越强大。开始时由于技术方面的限制，网卡只有10Mbps的吞吐量，由于网络技术的发展，100Mbps吞吐量的网卡开始在市场上得到广泛的应用。而现在1000Mbps吞吐量的网卡的出现又给网络的传输带来了新的活力。 论文中主要阐述了基于以太网的USB TO Gigabit LAN网卡的设计与制作。论文首先对以太网进行了介绍，紧接着讲了网卡的基本知识。随后又对USB TO Gigabit LAN网卡的电路设计和制作进行了详细的描述。论文还包括了USB TO Gigabit LAN网卡的调试等内容。
上传时间： 2014-12-02
上传用户：wab1981
介绍一种简单射频识别系统设计。该设计包括阅读器、应答器和线圈3部分。由单片机控制阅读器向应答器发射无线信号，并接收应答器回送的信号，再通过分析回送信号识别物品。阅读器和应答器之间以半双工通信方式通信。 Abstract: A simple design of radio frequency identification system is given in this paper.The design includes reader,responder and winding.Through MCU，signals are sent to responder from reader，then corresponding signals are sent back. According to the analysis of the signals sent back，the objects can be identified.Half-duplex communication is adopted? between? reader? and? responder.
上传时间： 2013-10-11
上传用户：plsee
The MAX3243E device consists of three line drivers, five line receivers, and a dual charge-pump circuit with±15-kV ESD (HBM and IEC61000-4-2, Air-Gap Discharge) and ±8-kV ESD (IEC61000-4-2, Contact Discharge)protection on serial-port connection pins. The device meets the requirements of TIA/EIA-232-F and provides theelectrical interface between an asynchronous communication controller and the serial-port connector. Thiscombination of drivers and receivers matches that needed for the typical serial port used in an IBM PC/AT, orcompatible. The charge pump and four small external capacitors allow operation from a single 3-V to 5.5-Vsupply. In addition, the device includes an always-active noninverting output (ROUT2B), which allowsapplications using the ring indicator to transmit data while the device is powered down. The device operates atdata signaling rates up to 250 kbit/s and a maximum of 30-V/ms driver output slew rate.
标签： MULTICHANNEL 5.5 TO RS
上传时间： 2013-10-19
上传用户：ddddddd
特点 精确度0.25%滿刻度 ±1位數 输入配线系统可任意选择 CT比可任意设定 具有异常电流值与异常次数记录保留功能 电流过高或过低检测可任意设定 报警继电器复归方式可任意設定 尺寸小,穩定性高 2.主要規格 辅助电源: AC110V&220V ±20%(50 or 60Hz) AC220V&440V ±20%(50 or 60Hz)(optional) 精确度: 0.25% F.S. ±1 digit 输入负载: <0.2VA (Current) 最大过载能力 : Current related input: 2 x rated continuous 10 x rated 30 sec. 25 x rated 3sec. 50 x rated 1 sec. 输入电流范围: AC0-5A (10-1000Hz) CT ratio : 1-2000 adjustable 启动延迟动作时间: 0-99.9 second adjustable 继电器延迟动作时间: 0-99.9 second adjustable 继电器复归方式: Manual (N) / latch(L) can be modified 继电器磁滞范围: 0-999 digit adjustable 继电器动作方向: HI /LO/GO/HL can be modified 继电器容量: AC 250V-5A, DC 30V-7A 过载显示: "doFL" 温度系数: 50ppm/℃ (0-50℃) 显示幕: Red high efficiency LEDs high 14.22mm(.56")(PV) Red high efficiency LEDs high 14.22mm(.276")(NO) 参数设定方式: Touch switches 记忆型式 : Non-volatile E2PROM memory 绝缘耐压能力: 2KVac/1 min. (input/output/power) 1600Vdc(input/output 使用环境条件 : 0-50℃(20 to 90% RH non-condensed) 存放环境条件: 0-70℃(20 to 90% RH non-condensed) CE认证: EN 55022:1998/A1:2000 Class A EN 61000-3-2:2000 EN 61000-3-3:1995/A1:2001 EN 55024:1998/A1:2001
上传时间： 2013-10-14
上传用户：wanghui2438
特点 精确度0.1%滿刻度 ±1位數 可量測 交直流電流/交直流电压/電位計/傳送器/Pt-100/荷重元/電阻 等信号 显示范围-1999-9999可任意规划 具有异常值与异常次数记录保留功能 异常信号过高或过低或范围內或范围外检测可任意設定 报警继电器复归方式可任意設定 尺寸小,穩定性高 2.主要規格 精确度: 0.1% F.S. ±1 digit 0.2% F.S. ±1 digit(AC) 取样时间: 16 cycles/sec. 显示值范围: -1999 - +9999 digit adjustable 启动延迟动作时间: 0-99.9 second adjustable 继电器延迟动作时间: 0-99.9 second adjustable 继电器复归方式: Manual (N) / latch(L) can be modified 继电器动作方向: HI /LO/GO/HL can be modified 继电器容量: AC 250V-5A, DC 30V-7A 过载显示: "doFL" 温度系数: 50ppm/℃ (0-50℃) 显示幕: Red high efficiency LEDs high 14.22mm(.56")(PV) Red high efficiency LEDs high 7.0mm(.276")(NO) 参数设定方式: Touch switches 记忆型式 : Non-volatile E2PROM memory 绝缘耐压能力: 2KVac/1 min. (input/output/power) 1600Vdc(input/output 使用环境条件 : 0-50℃(20 to 90% RH non-condensed) 存放环境条件: 0-70℃(20 to 90% RH non-condensed) CE认证: EN 55022:1998/A1:2000 Class A EN 61000-3-2:2000 EN 61000-3-3:1995/A1:2001 EN 55024:1998/A1:2001
上传时间： 2013-11-02
上传用户：fandeshun
