-型ADC是现代语音频带、音频和高分辨率精密工业测量应用所青睐的转换器。
上传时间: 2013-11-14
上传用户:jiangshandz
当我们需要设计一个具有特定性能的DAC时,很可能没有任何一种架构是理想的。这种情况下,可以将两个或更多DAC组合成一个更高分辨率的DAC,以获得所需的性能。这些DAC可以是同一类型,也可以是不同类型,各DAC的分辨率无需相同
上传时间: 2014-12-23
上传用户:daoyue
1.前言 模块使用之前应注意如下的警告和注意事项。不正确的应用可能导致电击,模块损坏或着火的危险。请仔细阅读如下警告和注意事项:1.1警告:I. 不要触摸散热器和外壳,他们可能温度很高。II. 不要触摸输入端子或打开外壳触摸内部器件,他们可能存在高温或高压造成烫伤或电击。III. 当模块工作时,把你的手和脸远离模块,否则在模块异常时可能造成伤害。1.2注意事项:I. 请确认已按照使用说明书的要求正确连接输入输出管脚和信号管脚。II. 确保在模块的输入端连接一个快速熔断保险丝,以安全工作并满足安规要求。III. 模块电源属于元器件,安装和使用必须经专业设计人员进行设计。IV. 此系列模块电源属于一次变换,在应用中应注意符合安全规范。V. 模块的输入、输出端属于危险能量,必须保证终端用户不能接触到。设备制造商必须保证模块输出不易被服务工程师短路或工程师遗落的金属部件短路。VI. 应用电路和参数仅供参考,在完成应用电路设计之前必须对参数和电路进行验证。VII. 这篇文档的更改不能保证及时通知客户,在实际使用中,请注意最新的应用说明。
上传时间: 2013-11-17
上传用户:luke5347
高压配电网的保护措施有:一、电网相间短路的电流保护。正常运行时输电线路上流过负荷电流,母线电压约为额定电压。当输电线路发生短路时,故障相电流增大。根据这一特征,可以构成反应故障时电流增大而动作的电流保护。对于输电线路相间短路通常采用三段式电流保护即无时限电流速断保护(电流I段),限时电流速断保护(电流II段),和定时限过电流保护(电流III段)。其中电流I段、II段共同构成线跌的主保护。III段为后备保护。1、无时限电流速断保护。在保证选择性和可靠性的前提下,根据对继电保护快速性的要求,原则上应装设快速动作的保护装置,使切除故障的时间尽可能短。反应电流增加,且不带时限动作的电流保护称为无时限电流速断保护。在单侧电源辐射形电网为切除线路故障,需在每条线跌电源侧装设断路器和相应的保护。假设线路L1、L2分别装有电流速断保护1和保护2,当线路L1上发生短路时,希望保护1能瞬时动作。但从选择要求出发,在下一条线路即L2首端K2点短路时,保护1能瞬时动作。但从选择性要求出发,在下一条线路L2首端K2点短路时,保护1不应动作,而应由保护2动作切除故障,为使保护1在K2点短路时不起动,必须使它的动作电流大于K2点短路时的最大短路电流,又称作按躲过一下条线路出口处短路的条件整定。
上传时间: 2013-11-16
上传用户:zhengjian
I/O 型单片机使用手册 目录 间接寻址寄存器 – IAR, IAR0, IAR1 .............................................35间接寻址指针 – MP, MP0, MP1 ......................................................35存储区指针 – BP .........................................................................36累加器 – ACC...................................................................................37程序计数器低字节寄存器 – PCL....................................................37表格寄存器 – TBLP,TBHP,TBLH....................................................37看门狗定时寄存器 – WDTS............................................................38状态寄存器 – STATUS.....................................................................38中断控制寄存器 – INTC,INTC0,INTC1 .........................................39定时/计数寄存器...............................................................................39输入/输出端口和控制寄存器...........................................................40UART 寄存器 .USR,UCR1,UCR2,TXR/RXR,BRG.......................40输入/输出端口..........................................................................................41上拉电阻............................................................................................41PA 口的唤醒......................................................................................41输入/输出端口控制寄存器...............................................................41引脚共享功能....................................................................................42编程注意事项....................................................................................45定时/计数器..............................................................................................46配置定时/计数器输入时钟源...........................................................47定时/计数寄存器 – TMR, TMR0,TMR0L/TMR0H,TMR1L/TMR1H,TMR2.....................................................................49定时/计数控制寄存器 – TMRC,TMR0C,TMR1C,TMR2C............50定时器模式........................................................................................53事件计数器模式................................................................................53脉冲宽度测量模式............................................................................54可编程分频器(PFD)和蜂鸣器的应用..............................................55预分频器(Prescaler)...........................................................................56输入/输出接口...................................................................................56编程注意事项....................................................................................57定时/计数器应用范例.......................................................................57中断............................................................................................................59中断寄存器........................................................................................59中断优先权........................................................................................62外部中断............................................................................................63定时/计数器中断...............................................................................64UART 中断........................................................................................64编程注意事项....................................................................................65复位和初始化............................................................................................66复位....................................................................................................66目录iii异步串行口——UART............................................................................74UART 特性..........................................................................................74UART 外部引脚..................................................................................74数据发送.............................................................................................75UART 状态控制寄存器......................................................................75波特率发生器.....................................................................................79UART 设置与控制..............................................................................81UART 发送器......................................................................................83UART 接收器......................................................................................84接收错误处理.....................................................................................85接收中断图解.....................................................................................86地址检测模式.....................................................................................86暂停模式下的UART 功能.................................................................87UART 应用范例.................................................................................87振荡器........................................................................................................89系统时钟配置....................................................................................89系统晶体/陶瓷振荡器.......................................................................89系统电阻电容振荡器........................................................................90内部系统电阻电容振荡器................................................................90RTC 振荡器........................................................................................91看门狗定时振荡器............................................................................91暂停和唤醒................................................................................................92暂停.....................................................................................................92进入暂停.............................................................................................92静态电流.............................................................................................92唤醒....................................................................................................92看门狗定时器............................................................................................94掩膜选项....................................................................................................96应用电路....................................................................................................97第二部份 程序语言.....................................................................99第二章 指令集介绍.................................................................................101指令集......................................................................................................101指令周期..........................................................................................101数据的传送......................................................................................101算术运算..........................................................................................102逻辑和移位运算..............................................................................102分支和控制的转换..........................................................................102位运算..............................................................................................102查表运算..........................................................................................103其它运算..........................................................................................103指令设定一览表......................................................................................104惯例..................................................................................................104I/O 型单片机使用手册iv第三章 指令定义.....................................................................................107第四章 汇编语言和编译器.....................................................................121常用符号..................................................................................................121语句语法..................................................................................................122名称..................................................................................................122操作项..............................................................................................122操作数项..........................................................................................122注解..................................................................................................122编译伪指令..............................................................................................123条件编译伪指令..............................................................................123文件控制伪指令..............................................................................124程序伪指令......................................................................................126数据定义伪指令..............................................................................130宏指令..............................................................................................132汇编语言指令..........................................................................................136名称..................................................................................................136助记符..............................................................................................136操作数、运算子和表达式..............................................................136其它..........................................................................................................139前置引用..........................................................................................139局部标号..........................................................................................139汇编语言保留字..............................................................................140编译器选项..............................................................................................141编译列表文件格式..................................................................................141源程序列表......................................................................................141编译总结..........................................................................................142其它..................................................................................................142第三部份 开发工具................................................................... 145第五章 单片机开发工具.........................................................................147HT-IDE 集成开发环境............................................................................147盛群单片机仿真器(HT-ICE) ..................................................................149HT-ICE 接口卡.................................................................................149OTP 烧写器.....................................................................................149OTP 适配卡.....................................................................................149系统配置..................................................................................................150HT-ICE 接口卡设置........................................................................151安装..........................................................................................................153系统要求..........................................................................................153硬件安装..........................................................................................153软件安装..........................................................................................154目录v第六章 快速开始.....................................................................................159步骤一:建立一个新项目..............................................................159步骤二:将源程序文件加到项目中..............................................159步骤三:编译项目..........................................................................159步骤四:烧写OTP 单片机.............................................................160步骤五:传送程序与掩膜选项单至Holtek ..................................160附录............................................................................................... 161附录A 特性曲线图...................................................................................163附录B 封装信息.......................................................................................173
上传时间: 2013-10-18
上传用户:blacklee
安规设计注意事项1. 件选用(1) 在件选用方面,要求掌握:a .安规件有哪些?(见三.安规件介绍)b.安规件要求安规件的要求就是要取得安规机构的认证或是符合相关安规标准;c.安规件额定值任何件均必须依 MANUFACTURE 规定的额定值使用;I 额定电压;II 额定电;III 温额定值;(2). 件的温升限制a. 一般电子件: 依件规格之额定温值,决定其温上限b. 线圈类: 依其绝缘系统耐温决定Class A ΔT≦75℃Class E ΔT≦90℃Class B ΔT≦95℃Class F ΔT≦115℃Class H ΔT≦140℃c. 人造橡胶或PVC 被覆之线材及电源线类:有标示耐温值 T 者ΔT≦(T-25)℃无标示耐温值 T 者ΔT≦50℃d. Bobbin 类: 无一定值,但须做125℃球压测试;e. 端子类: ΔT≦60℃f. 温升限值I. 如果有规定待测物的耐温值(Tmax),则:ΔT≦Tmax-TmraII. 如果有规定待测物的温升限值(ΔTmax),则:ΔT≦ΔTmax+25-Tmra其中 Tmra=制造商所规定的设备允许操作室温或是25℃
上传时间: 2013-10-14
上传用户:674635689
PLC TM卡开发系统汇编程序(ATM8051) ;***************** 定义管脚*************************SCL BIT P1.0SDA BIT P1.1GC BIT P1.2BZ BIT P3.6LEDI BIT P1.4LEDII BIT P1.5OK BIT 20H.1OUT1 BIT P1.3OUT2 BIT P1.0OUT3 BIT P1.1RXD BIT P3.0TXD BIT P3.1PCV BIT P3.2WPC BIT P3.3RPC BIT P3.5LEDR BIT P3.4LEDL BIT P3.6TM BIT P3.7;********************定义寄存器***********************ROMDTA EQU 30H;NUMBY EQU 61H;SLA EQU 60H;MTD EQU 2FH;MRD EQU 40H;TEMP EQU 50H;;ORG 00H;;INDEX:MOV P1, #00H;MOV P2, #0FFHMOV MTD ,#00HCALL REEMOV R0,40HCJNE R0,#01,NO;MOV P2,#1CHLJMP VIMEN MOV P2,#79HACALL TOUCHRESET ;JNC NO ;CALL READTM ;CJNE A,#01H,NO;NOPMOV MTD, #00HCALL WEENOPMOV P2,#4AHSETB BZCALL TIMECLR BZMOV PCON, #0FFHVIME:CALL TIME1CALL TOUCHRESETJNC VIMECALL READTMCJNE A, #01H,VIME;NOPNOPNOPIII: MOV MTD,#00HCALL REECALL BBJNB OK,NO1LJMP ZHUNO1:MOV MTD,#10H
上传时间: 2014-03-24
上传用户:448949
This application note describes how to implement the Bus LVDS (BLVDS) interface in the supported Altera ® device families for high-performance multipoint applications. This application note also shows the performance analysis of a multipoint application with the Cyclone III BLVDS example.
标签: Implementing LVDS 522 Bus
上传时间: 2013-11-10
上传用户:frank1234
本文采用Altera公司的FPGA器件Cyclone III系列EP3C10作为核心器件构成了R-S(255,223)编码系统;利用Quartus II 9.0作为硬件仿真平台,用硬件描述语言Verilog_HDL实现编程,并且通过JTAG接口与EP3C10连接。R-S(Reed-Solomon)码是一类纠错能力很强的特殊的非二进制BCH码,能应对随机性和突发性错误,广泛应用于各种通信系统中和保密系统中。R-S(255,223)码能够检测32字节长度和纠错16字节长度的连续数据错误信息。
标签: CycloneIII RS编码
上传时间: 2013-11-07
上传用户:exxxds
针对固定码长Turbo码适应性差的缺点,以LTE为应用背景,提出了一种帧长可配置的Turbo编译码器的FPGA实现方案。该设计可以依据具体的信道环境和速率要求调节信息帧长,平衡译码性能和系统时延。方案采用“自顶向下”的设计思想和“自底而上”的实现方法,对 Turbo编译码系统模块化设计后优化统一,经时序仿真验证后下载配置到Altera公司Stratix III系列的EP3SL150F1152C2N中。测试结果表明,系统运行稳健可靠,并具有良好的移植性;集成化一体设计,为LTE标准下Turbo码 ASIC的开发提供了参考。
上传时间: 2013-10-28
上传用户:d815185728