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.
上傳時間： 2014-12-24
上傳用戶：熊少鋒
長電c2383 TO-92L
上傳時間： 2013-11-09
上傳用戶：wvbxj
高的工作電壓高達100V N雙N溝道MOSFET同步驅動 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.
上傳時間： 2013-10-24
上傳用戶：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.
上傳時間： 2014-12-24
上傳用戶：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.
上傳時間： 2013-10-09
上傳用戶：hanhanj
畢業設計 USB TO Gigabit LAN 網卡 隨著網絡技術飛速發展，多媒體的應用越來越多，人們對網絡的要求也越來越高，為了適應市場的需求，網卡出現了。它以其結構簡單、成本低廉、兼容性強等諸多的優越性得到了廣泛的應用。由于網絡的應用越來越廣泛，網卡的應用也越來越多、功能越來越強大。開始時由于技術方面的限制，網卡只有10Mbps的吞吐量，由于網絡技術的發展，100Mbps吞吐量的網卡開始在市場上得到廣泛的應用。而現在1000Mbps吞吐量的網卡的出現又給網絡的傳輸帶來了新的活力。 論文中主要闡述了基于以太網的USB TO Gigabit LAN網卡的設計與制作。論文首先對以太網進行了介紹，緊接著講了網卡的基本知識。隨后又對USB TO Gigabit LAN網卡的電路設計和制作進行了詳細的描述。論文還包括了USB TO Gigabit LAN網卡的調試等內容。
上傳時間： 2014-12-02
上傳用戶：wab1981
介紹一種簡單射頻識別系統設計。該設計包括閱讀器、應答器和線圈3部分。由單片機控制閱讀器向應答器發射無線信號，并接收應答器回送的信號，再通過分析回送信號識別物品。閱讀器和應答器之間以半雙工通信方式通信。 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.
上傳時間： 2013-10-11
上傳用戶：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.
標簽： MULTICHANNEL 5.5 TO RS
上傳時間： 2013-10-19
上傳用戶：ddddddd
特點 精確度0.25%滿刻度 ±1位數 輸入配線系統可任意選擇 CT比可任意設定 具有異常電流值與異常次數記錄保留功能 電流過高或過低檢測可任意設定 報警繼電器復歸方式可任意設定 尺寸小,穩定性高 2.主要規格 輔助電源: AC110V&220V ±20%(50 or 60Hz) AC220V&440V ±20%(50 or 60Hz)(optional) 精確度: 0.25% F.S. ±1 digit 輸入負載: <0.2VA (Current) 最大過載能力 : Current related input: 2 x rated continuous 10 x rated 30 sec. 25 x rated 3sec. 50 x rated 1 sec. 輸入電流范圍: AC0-5A (10-1000Hz) CT ratio : 1-2000 adjustable 啟動延遲動作時間: 0-99.9 second adjustable 繼電器延遲動作時間: 0-99.9 second adjustable 繼電器復歸方式: Manual (N) / latch(L) can be modified 繼電器磁滯范圍: 0-999 digit adjustable 繼電器動作方向: HI /LO/GO/HL can be modified 繼電器容量: AC 250V-5A, DC 30V-7A 過載顯示: "doFL" 溫度系數: 50ppm/℃ (0-50℃) 顯示幕: Red high efficiency LEDs high 14.22mm(.56")(PV) Red high efficiency LEDs high 14.22mm(.276")(NO) 參數設定方式: Touch switches 記憶型式 : Non-volatile E2PROM memory 絕緣耐壓能力: 2KVac/1 min. (input/output/power) 1600Vdc(input/output 使用環境條件 : 0-50℃(20 to 90% RH non-condensed) 存放環境條件: 0-70℃(20 to 90% RH non-condensed) CE認證: EN 55022:1998/A1:2000 Class A EN 61000-3-2:2000 EN 61000-3-3:1995/A1:2001 EN 55024:1998/A1:2001
上傳時間： 2013-10-14
上傳用戶：wanghui2438
特點 精確度0.1%滿刻度 ±1位數 可量測 交直流電流/交直流電壓/電位計/傳送器/Pt-100/荷重元/電阻 等信號 顯示范圍-1999-9999可任意規劃 具有異常值與異常次數記錄保留功能 異常信號過高或過低或范圍內或范圍外檢測可任意設定 報警繼電器復歸方式可任意設定 尺寸小,穩定性高 2.主要規格 精確度: 0.1% F.S. ±1 digit 0.2% F.S. ±1 digit(AC) 取樣時間: 16 cycles/sec. 顯示值范圍: -1999 - +9999 digit adjustable 啟動延遲動作時間: 0-99.9 second adjustable 繼電器延遲動作時間: 0-99.9 second adjustable 繼電器復歸方式: Manual (N) / latch(L) can be modified 繼電器動作方向: HI /LO/GO/HL can be modified 繼電器容量: AC 250V-5A, DC 30V-7A 過載顯示: "doFL" 溫度系數: 50ppm/℃ (0-50℃) 顯示幕: Red high efficiency LEDs high 14.22mm(.56")(PV) Red high efficiency LEDs high 7.0mm(.276")(NO) 參數設定方式: Touch switches 記憶型式 : Non-volatile E2PROM memory 絕緣耐壓能力: 2KVac/1 min. (input/output/power) 1600Vdc(input/output 使用環境條件 : 0-50℃(20 to 90% RH non-condensed) 存放環境條件: 0-70℃(20 to 90% RH non-condensed) CE認證: EN 55022:1998/A1:2000 Class A EN 61000-3-2:2000 EN 61000-3-3:1995/A1:2001 EN 55024:1998/A1:2001
上傳時間： 2013-11-02
上傳用戶：fandeshun
