The LTM4601 DC/DC μModule regulator is a completehigh power density stepdown regulator for up to 12Acontinuous (14A peak) loads. The device is housed ina small 15mm ¥ 15mm ¥ 2.8mm LGA surface mountpackage, thus the large power dissipation is a challengein some applications. This thermal application note willprovide guidelines for using the μModule regulator inambient environments with or without air fl ow. Loadcurrent derating curves are provided for several inputvoltages and output voltages versus ambient temperatureand air fl ow.
The LTM4600 DC/DC μModule regulator is a complete highpower density stepdown regulator for 10A continuous (14Apeak) loads. The device has two voltage options: 20VINmaximum for the LTM4600EV and 28VIN maximum for theLTM4600HVEV each housed in a small 15mm ¥ 15mm ¥2.8mm LGA surface mount package.
為滿足礦井安全生產(chǎn)要求，介紹了一種以AT89C51單片機(jī)為主控器，對環(huán)境空氣的溫度、有毒易燃?xì)怏w的濃度等進(jìn)行檢測的監(jiān)控系統(tǒng)。該系統(tǒng)配合外圍電路能實(shí)現(xiàn)對上述環(huán)境指標(biāo)的控制并存儲相關(guān)數(shù)據(jù)與上位PC機(jī)通信。它采用硬件抗干擾和軟件抗干擾技術(shù)，以確保整個系統(tǒng)工作的準(zhǔn)確性。
Abstract:
In order to meet the needs of mine produce safety，a kind of intellignet mine ambient monotoring and control system based on AT89C51 is introduced.This system can detect the temperature of ambient of mine，the density of poisonous inflammable gas,combined external circuit.With its function part， this system can change above-mentioned elements.
LLCR Pin Socket Testing with the Model 3732 High density Matrix Card
Computer processors (CPUs) today have come a long way from the computer processors of the past. They draw more power, run at lower voltages, and have more pins than ever before.
The AT89C52 is a low-power, high-performance CMOS 8-bit microcomputer with 8Kbytes of Flash programmable and erasable read only memory (PEROM). The deviceis manufactured using Atmel’s high-density nonvolatile memory technology and iscompatible with the industry-standard 80C51 and 80C52 instruction set and pinout.The on-chip Flash allows the program memory to be reprogrammed in-system or by aconventional nonvolatile memory programmer. By combining a versatile 8-bit CPUwith Flash on a monolithic chip, the Atmel AT89C52 is a powerful microcomputerwhich provides a highly-flexible and cost-effective solution to many embedded controlapplications.
HDB3(High density Bipolar三階高密度雙極性)碼是在AMI碼的基礎(chǔ)上改進(jìn)的一種雙極性歸零碼，它除具有AMI碼功率譜中無直流分量，可進(jìn)行差錯自檢等優(yōu)點(diǎn)外，還克服了AMI碼當(dāng)信息中出現(xiàn)連“0”碼時定時提取困難的缺點(diǎn)，而且HDB3碼頻譜能量主要集中在基波頻率以下，占用頻帶較窄，是ITU-TG.703推薦的PCM基群、二次群和三次群的數(shù)字傳輸接口碼型,因此HDB3碼的編解碼就顯得極為重要了[1]。目前，HDB3碼主要由專用集成電路及相應(yīng)匹配的外圍中小規(guī)模集成芯片來實(shí)現(xiàn)，但集成程度不高，特別是位同步提取非常復(fù)雜，不易實(shí)現(xiàn)。隨著可編程器件的發(fā)展，這一難題得到了很好地解決。
Designing withProgrammable Logicin an Analog WorldProgrammable logic devicesrevolutionized digital design over 25years ago, promising designers a blankchip to design literally any functionand program it in the field. PLDs canbe low-logic density devices that usenonvolatile sea-of-gates cells calledcomplex programmable logic devices(CPLDs) or they can be high-densitydevices based on SRAM look-up tables
Designing withProgrammable Logicin an Analog WorldProgrammable logic devices revolutionizeddigital design over 25 years ago,promising designers a blank chip todesign literally any function and programit in the field. PLDs can be low-logicdensity devices that use nonvolatilesea-of-gates cells called complexprogrammable logic devices (CPLDs)or they can be high-density devicesbased on SRAM look-up tables (LUTs)
在車載自組網(wǎng)中，路由協(xié)議很大程度上決定了整個網(wǎng)絡(luò)的性能。如何有效的利用車流信息提高傳輸質(zhì)量是改善路由性能的一個關(guān)鍵問題。本文基于速度-密度線性模型，提出了一種實(shí)時車流密度的路由協(xié)議RVDR（Real-time Vehicle density Routing）。該協(xié)議通過與鄰居節(jié)點(diǎn)交換的速度信息，對相關(guān)道路車流密度進(jìn)行預(yù)測，并給出基于車流密度信息的路徑選擇方法。仿真結(jié)果表明，與現(xiàn)有協(xié)議相比，RVDR協(xié)議在實(shí)時性和高效性等性能方面得到改進(jìn)。
