Abstract: There are many things to consider WHEN designing a power supply for a field-programmablegate array (FPGA). These include (but are not limited to) the high number of voltage rails, and thediffering requirements for both sequencing/tracking and the voltage ripple limits. This application noteexplains these and other power-supply considerations that an engineer must think through WHENdesigning a power supply for an FPGA.
上傳時(shí)間: 2013-11-10
上傳用戶:iswlkje
多遠(yuǎn)程二極管溫度傳感器-Design Considerations for pc thermal management Multiple RDTS (remote diode temperature sensing) provides the most accurate method of sensing an IC’s junction temperature. It overcomes thermal gradient and placement issues encountered WHEN trying to place external sensors. PCB component count decreases WHEN using a device that provides multiple inputs.Better temperature sensing improves product performance and reliability. Disk drive data integrity suffers at elevated temperatures. IBM published an article stating that a 5°C rise in operating temperature causes a 15% increase in the drive’s failure rate. The overall performance of a system can be improved by providing a more accurate temperature measurement of the most critical devices allowing them to run just a few degrees hotter.The LM83 directly senses its own temperature and the temperature of three external PN junctions. One is dedicated to the CPU of choice, the other two go to other parts of your system that need thermal monitoring such as the disk drive or graphics chip. The SMBus-compatible LM83 supports SMBus timeout and logic levels. The LM83 has two interrupt outputs; one for user-programmable limits and WATCHDOG capability (INT), the other is a Critical Temperature Alarm output (T_CRIT_A) for system power supply shutdown.
標(biāo)簽: Considerat Design 遠(yuǎn)程 二極管
上傳時(shí)間: 2014-12-21
上傳用戶:ljd123456
The NCV7356 is a physical layer device for a single wire data linkcapable of operating with various Carrier Sense Multiple Accesswith Collision Resolution (CSMA/CR) protocols such as the BoschController Area Network (CAN) version 2.0. This serial data linknetwork is intended for use in applications where high data rate is notrequired and a lower data rate can achieve cost reductions in both thephysical media components and in the microprocessor and/ordedicated logic devices which use the network.The network shall be able to operate in either the normal data ratemode or a high-speed data download mode for assembly line andservice data transfer operations. The high-speed mode is onlyintended to be operational WHEN the bus is attached to an off-boardservice node. This node shall provide temporary bus electrical loadswhich facilitate higher speed operation. Such temporary loads shouldbe removed WHEN not performing download operations.The bit rate for normal communications is typically 33 kbit/s, forhigh-speed transmissions like described above a typical bit rate of83 kbit/s is recommended. The NCV7356 features undervoltagelockout, timeout for faulty blocked input signals, output blankingtime in case of bus ringing and a very low sleep mode current.
上傳時(shí)間: 2013-10-24
上傳用戶:s藍(lán)莓汁
The LPC2292/2294 microcontrollers are based on a 16/32-bit ARM7TDMI-S CPU with real-time emulation and embedded trace support, together with 256 kB of embedded high-speed flash memory. A 128-bit wide memory interface and a unique accelerator architecture enable 32-bit code execution at the maximum clock rate. For critical code size applications, the alternative 16-bit Thumb mode reduces code by more than 30 pct with minimal performance penalty. With their 144-pin package, low power consumption, various 32-bit timers, 8-channel 10-bit ADC, 2/4 (LPC2294) advanced CAN channels, PWM channels and up to nine external interrupt pins these microcontrollers are particularly suitable for automotive and industrial control applications as well as medical systems and fault-tolerant maintenance buses. The number of available fast GPIOs ranges from 76 (with external memory) through 112 (single-chip). With a wide range of additional serial communications interfaces, they are also suited for communication gateways and protocol converters as well as many other general-purpose applications. Remark: Throughout the data sheet, the term LPC2292/2294 will apply to devices with and without the /00 or /01 suffix. The suffixes /00 and /01 will be used to differentiate from other devices only WHEN necessary.
標(biāo)簽: lpc datasheet 2292 2294
上傳時(shí)間: 2014-12-30
上傳用戶:aysyzxzm
WHEN I started writing the first edition of RF Power Amplifiers for Wireless Communications,some time back in 1997, it seemed that I was roaming a largely uninhabitedlandscape. For reasons still not clear to me there were few, if any, otherbooks dedicated to the subject of RF power amplifiers. Right at the same time, however,hundreds of engineers were being assigned projects to design PAs for wirelesscommunications products. It was not, therefore, especially difficult to be successfulwith a book that was fortuitously at the right place and the right time.
標(biāo)簽: Communications Amplifiers Wireless Edition
上傳時(shí)間: 2013-11-12
上傳用戶:YYRR
Abstract: High-speed and low-speed data converters serve critical functions in modern broadband mobile radios. This application note outlines how todetermine high-speed data converter performance requirements in baseband sampling radio architectures. Also, system partition strategies andadvantages are outlined WHEN considering a high-speed analog front-end (AFE) solution.
標(biāo)簽: AFE 移動(dòng) 無線終端 導(dǎo)航
上傳時(shí)間: 2013-11-02
上傳用戶:jjj0202
Abstract: WHEN people want portable music, they usually rely on battery-powered audio devices. With a bit of engineeringblood (or curiosity) running in your veins, it is not difficult to build a wireless Bluetooth® stereo audio system that can becontrolled with any device that has a Bluetooth connection and a music player
標(biāo)簽: 無線藍(lán)牙 立體聲 音頻系統(tǒng)
上傳時(shí)間: 2013-10-09
上傳用戶:天空說我在
ZigBee技術(shù)是一種應(yīng)用于短距離范圍內(nèi),低傳輸數(shù)據(jù)速率下的各種電子設(shè)備之間的無線通信技術(shù)。ZigBee名字來源于蜂群使用的賴以生存和發(fā)展的通信方式,蜜蜂通過跳ZigZag形狀的舞蹈來通知發(fā)現(xiàn)的新食物源的位置、距離和方向等信息,以此作為新一代無線通訊技術(shù)的名稱。ZigBee過去又稱為“HomeRF Lite”、“RF-EasyLink”或“FireFly”無線電技術(shù),目前統(tǒng)一稱為ZigBee技術(shù)。 2、ZigBee技術(shù)的特點(diǎn) 自從馬可尼發(fā)明無線電以來,無線通信技術(shù)一直向著不斷提高數(shù)據(jù)速率和傳輸距離的方向發(fā)展。例如:廣域網(wǎng)范圍內(nèi)的第三代移動(dòng)通信網(wǎng)絡(luò)(3G)目的在于提供多媒體無線服務(wù),局域網(wǎng)范圍內(nèi)的標(biāo)準(zhǔn)從IEEE802.11的1Mbit/s到IEEE802.11g的54Mbit/s的數(shù)據(jù)速率。而當(dāng)前得到廣泛研究的ZigBee技術(shù)則致力于提供一種廉價(jià)的固定、便攜或者移動(dòng)設(shè)備使用的極低復(fù)雜度、成本和功耗的低速率無線通信技術(shù)。這種無線通信技術(shù)具有如下特點(diǎn): 功耗低:工作模式情況下,ZigBee技術(shù)傳輸速率低,傳輸數(shù)據(jù)量很小,因此信號(hào)的收發(fā)時(shí)間很短,其次在非工作模式時(shí),ZigBee節(jié)點(diǎn)處于休眠模式。設(shè)備搜索時(shí)延一般為30ms,休眠激活時(shí)延為15ms,活動(dòng)設(shè)備信道接入時(shí)延為15ms。由于工作時(shí)間較短、收發(fā)信息功耗較低且采用了休眠模式,使得ZigBee節(jié)點(diǎn)非常省電,ZigBee節(jié)點(diǎn)的電池工作時(shí)間可以長達(dá)6個(gè)月到2年左右。同時(shí),由于電池時(shí)間取決于很多因素,例如:電池種類、容量和應(yīng)用場合,ZigBee技術(shù)在協(xié)議上對(duì)電池使用也作了優(yōu)化。對(duì)于典型應(yīng)用,堿性電池可以使用數(shù)年,對(duì)于某些工作時(shí)間和總時(shí)間(工作時(shí)間+休眠時(shí)間)之比小于1%的情況,電池的壽命甚至可以超過10年。 數(shù)據(jù)傳輸可靠:ZigBee的媒體接入控制層(MAC層)采用talk-WHEN-ready的碰撞避免機(jī)制。在這種完全確認(rèn)的數(shù)據(jù)傳輸機(jī)制下,當(dāng)有數(shù)據(jù)傳送需求時(shí)則立刻傳送,發(fā)送的每個(gè)數(shù)據(jù)包都必須等待接收方的確認(rèn)信息,并進(jìn)行確認(rèn)信息回復(fù),若沒有得到確認(rèn)信息的回復(fù)就表示發(fā)生了碰撞,將再傳一次,采用這種方法可以提高系統(tǒng)信息傳輸?shù)目煽啃浴M瑫r(shí)為需要固定帶寬的通信業(yè)務(wù)預(yù)留了專用時(shí)隙,避免了發(fā)送數(shù)據(jù)時(shí)的競爭和沖突。同時(shí)ZigBee針對(duì)時(shí)延敏感的應(yīng)用做了優(yōu)化,通信時(shí)延和休眠狀態(tài)激活的時(shí)延都非常短。 網(wǎng)絡(luò)容量大:ZigBee低速率、低功耗和短距離傳輸?shù)奶攸c(diǎn)使它非常適宜支持簡單器件。ZigBee定義了兩種器件:全功能器件(FFD)和簡化功能器件(RFD)。對(duì)全功能器件,要求它支持所有的49個(gè)基本參數(shù)。而對(duì)簡化功能器件,在最小配置時(shí)只要求它支持38個(gè)基本參數(shù)。一個(gè)全功能器件可以與簡化功能器件和其他全功能器件通話,可以按3種方式工作,分別為:個(gè)域網(wǎng)協(xié)調(diào)器、協(xié)調(diào)器或器件。而簡化功能器件只能與全功能器件通話,僅用于非常簡單的應(yīng)用。一個(gè)ZigBee的網(wǎng)絡(luò)最多包括有255個(gè)ZigBee網(wǎng)路節(jié)點(diǎn),其中一個(gè)是主控(Master)設(shè)備,其余則是從屬(Slave)設(shè)備。若是通過網(wǎng)絡(luò)協(xié)調(diào)器(Network Coordinator),整個(gè)網(wǎng)絡(luò)最多可以支持超過64000個(gè)ZigBee網(wǎng)路節(jié)點(diǎn),再加上各個(gè)Network Coordinator可互相連接,整個(gè)ZigBee網(wǎng)絡(luò)節(jié)點(diǎn)的數(shù)目將十分可觀。 兼容性:ZigBee技術(shù)與現(xiàn)有的控制網(wǎng)絡(luò)標(biāo)準(zhǔn)無縫集成。通過網(wǎng)絡(luò)協(xié)調(diào)器(Coordinator)自動(dòng)建立網(wǎng)絡(luò),采用載波偵聽/沖突檢測(cè)(CSMA-CA)方式進(jìn)行信道接入。為了可靠傳遞,還提供全握手協(xié)議。
標(biāo)簽: zigbee
上傳時(shí)間: 2013-11-24
上傳用戶:siguazgb
This is the second half of our Transistor Circuits e-book. It contains a further 100 circuits, with many of them containing one or more Integrated Circuits (ICs).It's amazing what you can do with transistors but WHEN Integrated Circuits came along, the whole field of electronics exploded.
上傳時(shí)間: 2013-11-08
上傳用戶:603100257
This example shows how to update at regulate period the WWDG counter using theEarly Wakeup interrupt (EWI). The WWDG timeout is set to 262ms, refresh window set to 41h and the EWI isenabled. WHEN the WWDG counter reaches 40h the EWI is generated and in the WWDGISR the counter is refreshed to prevent a WWDG reset and led connected to PC.07is toggled.The EXTI line9 is connected to PB.09 pin and configured to generate an interrupton falling edge.In the NVIC, EXTI line9 to 5 interrupt vector is enabled with priority equal to 0and the WWDG interrupt vector is enabled with priority equal to 1 (EXTI IT > WWDG IT). The EXTI Line9 will be used to simulate a software failure: once the EXTI line9event occurs (by pressing Key push-button on EVAL board) the correspondent interruptis served, in the ISR the led connected to PC.07 is turned off and the EXTI line9pending bit is not cleared. So the CPU will execute indefinitely EXTI line9 ISR andthe WWDG ISR will never be entered(WWDG counter not updated). As result, WHEN theWWDG counter falls to 3Fh the WWDG reset occurs.If the EXTI line9 event don抰 occurs the WWDG counter is indefinitely refreshed inthe WWDG ISR which prevent from WWDG reset. If the WWDG reset is generated, after resuming from reset a led connected to PC.06is turned on. In this example the system is clocked by the HSE(8MHz).
上傳時(shí)間: 2013-11-11
上傳用戶:gundamwzc
蟲蟲下載站版權(quán)所有 京ICP備2021023401號(hào)-1