The latest generation of Texas Instruments (TI) boardmountedpower modules utilizes a pin interconnect technologythat improves surface-mount manufacturability.These modules are produced as a double-sided surfacemount(DSSMT) subassembly, yielding a case-less constructionwith subcomponents located on both sides of theprinted circuit board (PCB). Products produced in theDSSMT outline use the latest high-efficiency topologiesand magnetic-component packaging. This providescustomers with a high-efficiency, ready-to-use switchingpower module in a compact, space-saving package. Bothnonisolated point-of-load (POL) switching regulators andthe isolated dc/dc converter modules are being producedin the DSSMT outline.TI’s plug-in power product line offers power modules inboth through-hole and surface-mount packages. The surfacemountmodules produced in the DSSMT outline use asolid copper interconnect with an integral solder ball fortheir
上傳時(shí)間： 2013-10-10
上傳用戶(hù)：1184599859
單相橋式逆變電路為例：S1～S4是橋式電路的4個(gè)臂，由電力電子器件及輔助電路組成。S1、S4閉合，S2、S3斷開(kāi)時(shí)，負(fù)載電壓uo為正S1；S1、S4斷開(kāi)，S2、S3閉合時(shí)，uo為負(fù)，把直流電變成了交流電。改變兩組開(kāi)關(guān)切換頻率，可改變輸出交流電頻率。圖5-1 逆變電路及其波形舉例電阻負(fù)載時(shí)，負(fù)載電流io和uo的波形相同，相位也相同。阻感負(fù)載時(shí)，io滯后于uo，波形也不同（圖5-1b）。t1前：S1、S4通，uo和io均為正。t1時(shí)刻斷開(kāi)S1、S4，合上S2、S3，uo變負(fù)，但io不能立刻反向。io從電源負(fù)極流出，經(jīng)S2、負(fù)載和S3流回正極，負(fù)載電感能量向電源反饋，io逐漸減小，t2時(shí)刻降為零，之后io才反向并增大 （2）換流方式分類(lèi)換流——電流從一個(gè)支路向另一個(gè)支路轉(zhuǎn)移的過(guò)程，也稱(chēng)換相。開(kāi)通：適當(dāng)?shù)拈T(mén)極驅(qū)動(dòng)信號(hào)就可使其開(kāi)通。關(guān)斷：全控型器件可通過(guò)門(mén)極關(guān)斷。半控型器件晶閘管，必須利用外部條件才能關(guān)斷，一般在晶閘管電流過(guò)零后施加一定時(shí)間反壓，才能關(guān)斷。研究換流方式主要是研究如何使器件關(guān)斷。本章?lián)Q流及換流方式問(wèn)題最為全面集中，因此在本章講述1、器件換流利用全控型器件的自關(guān)斷能力進(jìn)行換流（Device Commutation）。2、電網(wǎng)換流由電網(wǎng)提供換流電壓稱(chēng)為電網(wǎng)換流（Line Commutation）?？煽卣麟娐?、交流調(diào)壓電路和采用相控方式的交交變頻電路，不需器件具有門(mén)極可關(guān)斷能力，也不需要為換流附加元件。3、負(fù)載換流由負(fù)載提供換流電壓稱(chēng)為負(fù)載換流（Load Commutation）。負(fù)載電流相位超前于負(fù)載電壓的場(chǎng)合，都可實(shí)現(xiàn)負(fù)載換流。負(fù)載為電容性負(fù)載時(shí)，負(fù)載為同步電動(dòng)機(jī)時(shí)，可實(shí)現(xiàn)負(fù)載換流。
上傳時(shí)間： 2013-10-15
上傳用戶(hù)：qingdou
一、 main.c(35): warning: #128-D: loop is not reachable from preceding code 原因，前面有一個(gè)while(1){ …….} 二、 main.c(54): warning: #1-D: last line of file ends without a newline 少了一個(gè)回車(chē)在}之后
上傳時(shí)間： 2014-12-26
上傳用戶(hù)：sjb555
為解決當(dāng)前計(jì)算機(jī)串行通訊接口只有USB，難以滿(mǎn)足舊型號(hào)設(shè)備或某些單片機(jī)要求RS232通訊的問(wèn)題，設(shè)計(jì)出兩款RS232/USB電路。采用CH341A與MAX223集成電路芯片構(gòu)建標(biāo)準(zhǔn)9線RS232/USB通用接口轉(zhuǎn)換器，無(wú)需編程。采用CH341A與PIC16F877A構(gòu)建單片機(jī)與計(jì)算機(jī)之間的USB通訊電路，軟件遵循RS232通訊協(xié)議，硬件進(jìn)行電平轉(zhuǎn)換。實(shí)際使用表明，這兩款產(chǎn)品與計(jì)算機(jī)端Windows 操作系統(tǒng)下的串口應(yīng)用程序完全兼容，且通訊過(guò)程中無(wú)握手失敗現(xiàn)象。 Abstract: To solve the problem that current computer serial communication only with USB interface can not satisfy with the old type equipments or MCU to communicate with RS232， two kinds of RS232/USB circuit were designed.CH341A and MAX223 integrated circuit chips were used to create a standard 9-line RS232/USB universal interface convertor without programme. CH341A and PIC16F877A chips were adopted to build the USB communication circuit between computers and MCU. The software follows RS232 communication protocol， and the hardware converts electrical levels. Actual practices indicate that the two manufactures are compatible with serial application program of Windows operation system completely，and get avoid of handshake lost.
上傳時(shí)間： 2013-11-03
上傳用戶(hù)：siying
提出一種基于凌陽(yáng)單片機(jī)的步進(jìn)電機(jī)加減速的控制方法。采用凌陽(yáng)科技推出的16位結(jié)構(gòu)工控單片機(jī)SPMC75F2413A為控制器，由Allegro公司生產(chǎn)的兩相步進(jìn)電機(jī)專(zhuān)用驅(qū)動(dòng)器件SLA7042M構(gòu)成步進(jìn)電機(jī)的驅(qū)動(dòng)電路，在傳統(tǒng)的3段直線加減速控制算法基礎(chǔ)上增加至7段S形曲線加減速過(guò)程，控制步進(jìn)電機(jī)的啟動(dòng)和停止。實(shí)驗(yàn)結(jié)果表明，該控制方法克服了直線加減速中不連續(xù)、易造成系統(tǒng)沖擊的問(wèn)題，整個(gè)系統(tǒng)實(shí)現(xiàn)柔性控制，電機(jī)啟動(dòng)、停止連續(xù)性能提高30%。 Abstract: The method of controlled stepping motor is referred based on SPMC75F2413A MCU， which adopts the 16 knots SPMC75F2413A MCU as the controller. The special-purpose actuation chip SLA7042M of two stepping motor produced by Allegro Corporation constituted to actuation electric circuit. The purpose of increasing to seven section of S shape curve based on the traditional three sections of straight line is to control the start and stop process of stepping motor. The experimental results show that the control method solves easy to pull-out and overshot problems. The overall system realizes flexible control， and the performance of motor start or stop continuity is increased 30%
標(biāo)簽： 凌陽(yáng)單片機(jī) 步進(jìn)電機(jī) 減 控制方法
上傳時(shí)間： 2013-12-08
上傳用戶(hù)：jiangfire
單片機(jī)作為一種微型計(jì)算機(jī)，其內(nèi)部具有一定的存儲(chǔ)單元（8031除外），但由于其內(nèi)部存儲(chǔ)單元及端口有限，很多情況下難以滿(mǎn)足實(shí)際需求。為此介紹一種新的擴(kuò)展方法，將數(shù)據(jù)線與地址線合并使用，通過(guò)軟件控制的方法實(shí)現(xiàn)數(shù)據(jù)線與地址線功能的分時(shí)轉(zhuǎn)換，數(shù)據(jù)線不僅用于傳送數(shù)據(jù)信號(hào)，還可作為地址線、控制線，用于傳送地址信號(hào)和控制信號(hào)，從而實(shí)現(xiàn)單片機(jī)與存儲(chǔ)器件的有效連接。以單片機(jī)片外256KB數(shù)據(jù)存儲(chǔ)空間的擴(kuò)展為例，通過(guò)該擴(kuò)展方法，僅用10個(gè)I/O端口便可實(shí)現(xiàn)，與傳統(tǒng)的擴(kuò)展方法相比，可節(jié)約8個(gè)I/O端口。 Abstract: As a micro-computer,the SCM internal memory has a certain units(except8031),but because of its internal storage units and the ports are limited,in many cases it can not meet the actual demand.So we introduced a new extension method,the data line and address lines combined through software-controlled approach to realize the time-conversion functions of data lines and address lines,so the data lines not only transmited data signals,but also served as address lines and control lines to transmit address signals and control signals,in order to achieve an effective connection of microcontroller and memory chips.Take microcontroller chip with256KB of data storage space expansion as example,through this extension method,with only10I/O ports it was achieved,compared with the traditional extension methods,this method saves8I/O ports.
標(biāo)簽： 單片機(jī) P0口 數(shù)據(jù)存儲(chǔ)器 擴(kuò)展
上傳時(shí)間： 2014-12-26
上傳用戶(hù)：adada
詳細(xì)介紹工控軟件組態(tài)王與單片機(jī)多機(jī)串口通訊的設(shè)計(jì)原理。分析組態(tài)王提供的直接與單片機(jī)串口通信方法的優(yōu)點(diǎn)，給出系統(tǒng)基于RS-485總線傳輸?shù)慕涌陔娐吩韴D。根據(jù)組態(tài)王提供的通訊協(xié)議和單片機(jī)多機(jī)串口通訊的原理，給出程序設(shè)計(jì)流程與思路。 Abstract: In this paper，the design principle of communication between multi-SCM and KingView by serial ports is described in detail.We analysis the advantage of method supplied by KingView,by which KingView can communicate with serial ports of SCM directly，and provide the system’s interface circuit based on the RS-485transmission line.We provide flow diagram of programming and thinking on the basis of communication protocol supplied by KingView and principle of communication among multi-SCM through serial ports.
標(biāo)簽： 工控軟件 單片機(jī) 串口通訊 多機(jī)
上傳時(shí)間： 2013-12-19
上傳用戶(hù)：tecman
Mega16是一款采用先進(jìn)RISC精簡(jiǎn)指令，內(nèi)置A/D的8位單片機(jī)，可支持低電壓聯(lián)機(jī) Flash和EEPROM 寫(xiě)入功能；同時(shí)還支持 Basic和C 等高級(jí)語(yǔ)言編程。用它設(shè)計(jì)電子時(shí)鐘不僅成本低，硬件簡(jiǎn)單，而且很容易實(shí)現(xiàn)系統(tǒng)移植。介紹了如何利用AVR系列單片機(jī)Mega16及1602字符液晶來(lái)設(shè)計(jì)電子時(shí)鐘的方法，同時(shí)給出了相應(yīng)的電路原理及部分語(yǔ)言程序。 Abstract: ?Mega16 is a high-performance, low power consumption, the use of advanced RISC concise instructions, built-in A/D 8-bit microcontrollers, the on-line support for low-voltage Flash, EEPROM write function. Except Mega16 also support the Basic, C, and other high-level language programming.The electronic clock which is deisgned by Mega16 is not only low-cost, simple hardware, but easy to achieve system migration.The design method of electrioic clock based on the AVR Mega16 and character LCD1602 is introduced in this paper,and the corresponding circuit electrionic and some language program are given.
上傳時(shí)間： 2014-12-27
上傳用戶(hù)：zl5712176
詳細(xì)介紹了TLC1549系列模數(shù)轉(zhuǎn)換器的特點(diǎn)及工作原理，然后根據(jù)TLC1549的工作時(shí)序和A/D轉(zhuǎn)換原理針對(duì)實(shí)際問(wèn)題編寫(xiě)了詳細(xì)的匯編語(yǔ)言程序。 Abstract: A basic principle and characteristic of TLC1549 analog-to-digital converter are introduced? detailedly in this article.Through engineering-oriented illustration,a microcomputer programmer base on basic principle and time sequence of TLC1549 is writted.
上傳時(shí)間： 2014-07-16
上傳用戶(hù)：blans
The PCF8578 is a low power CMOS1 LCD row and column driver, designed to drive dotmatrix graphic displays at multiplex rates of 1:8, 1:16, 1:24 or 1:32. The device has40 outputs, of which 24 are programmable and configurable for the following ratios ofrows/columns: 32¤8, 24¤16, 16¤24 or 8¤32. The PCF8578 can function as a stand-alone LCDcontroller and driver for use in small systems. For larger systems it can be used inconjunction with up to 32 PCF8579s for which it has been optimized. Together these twodevices form a general purpose LCD dot matrix driver chip set, capable of driving displaysof up to 40960 dots. The PCF8578 is compatible with most microcontrollers andcommunicates via a two-line bidirectional bus (I2C-bus). Communication overhead isminimized by a display RAM with auto-incremented addressing and display bankswitching.
標(biāo)簽： 8578 PCF LCD 圖形點(diǎn)陣
上傳時(shí)間： 2013-10-23
上傳用戶(hù)：頂?shù)弥?/p>
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