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摘要: http://www.21say.com/askookfskgfsk%E6%98%AF%E4%BB%80%E4%B9%88/ASK是幅移键控调制的简写,例如二进制的,把二进制符号0和1分别用不同的幅度来表示,就是ASK了。而OOK则是ASK调制的一个特例,把一个幅度取为0,另一个幅度为非0,就是OOK了。例如二进制符号0用不发射载波表示,二进制1用发射1表示。ASK跟OOK的频谱都比较宽。FSK是频移键控调制的简写,即用不同的频率来表示不同的符号。例如2KHz表示符号0,3KHz表示符号1。GFSK是高斯频移键控的简写,在调制之前通过一个高斯低通滤波器来限制信号的频谱宽度。http://blo 阅读全文
posted @ 2013-08-04 12:48 IAmAProgrammer 阅读(2526) 评论(0) 推荐(0) 编辑
摘要: 针对现在市场上日益更新的遥控器种类,本公司经过长时间的研究,推出新一代拷贝机,本产品有以下特点:1. 众多车库门遥控分析信息被集成在一台机器内,只要一种遥控器,就可以复制众多品牌的车库遥控.免去积压各种车库遥控的烦恼.兼容固定码,电子码,及部份滚动码.方便维修检测.2. 本遥控分析义,加入了部份原车的遥控信息,可以直接复制,方便改折叠或维修遥控.也可以复制再生, 不与原遥控 ,帮客人增加一个新的遥控. 原车遥控信息,包含F3.长城,新凯越,花冠,威驰,江淮,江铃........一系列原车遥控信息.随着我们的努力,会有更多原车遥控通过无线升级,帮您免费添加.3. 具有高精度频率检测功能,可从25 阅读全文
posted @ 2013-08-04 11:30 IAmAProgrammer 阅读(6600) 评论(0) 推荐(0) 编辑
摘要: http://taobao.autos.cn.yahoo.com/ypen/20111128/725214.html近日,在车友论坛上的一个热帖《悲喜交加:1分钟就能复制汽车遥控器?》在网上发布之后,引起了众人的关注和热烈讨论。帖子里称,车库遥控器和汽车防盗器的遥控器都是可以复制的,而复制像这样的遥控器一般用一分钟的时间就可以完成,对于不同的遥控器会有不同的“遥控复制器”来复制。网友大呼,如果连汽车防盗器都能这么轻易就被打开,那怎么样才能让车子安全呢?市场上有没有无法破解的汽车防盗器呢?文中所讲的“复制遥控器”,实际上就是通过解码技术核对开锁,只要发射器的频率和密码能够破解就能够开锁。传统的单 阅读全文
posted @ 2013-08-04 11:07 IAmAProgrammer 阅读(865) 评论(0) 推荐(0) 编辑
摘要: http://www.auto-diagnostics.info/j1850j1850The SAE J1850 bus bus is used for diagnostics and data sharing applications in vehicles. The J1850 bus takes two forms:41.6Kbps Pulse Width Modulated (PWM) two wire differential approach (Ford vehicles)10.4Kbps Variable Pulse Width (VPW) single wire approac 阅读全文
posted @ 2013-08-04 07:27 IAmAProgrammer 阅读(7903) 评论(0) 推荐(0) 编辑
摘要: http://amarkham.com/?p=49 阅读全文
posted @ 2013-08-03 22:51 IAmAProgrammer 阅读(532) 评论(0) 推荐(0) 编辑
摘要: http://www.ti.com/lit/an/spraa88a/spraa88a.pdfhttp://www.ti.com/litv/zip/spraa88aThe high-resolution PWM on the TMS320F280x DSP family has been used to implement a digital-to-analog converter with the addition of an external analog low-pass filter. Such an approach can offer a lower-cost alternative 阅读全文
posted @ 2013-08-03 21:13 IAmAProgrammer 阅读(653) 评论(0) 推荐(0) 编辑
摘要: http://www.xilinx.com/support/answers/35171.htmHow to connect the following pins in my design?CMPMISOCMPMOSICMPCLKCMPCS_BCMPMISO - Reserved for future use. Use these pins as general-purpose I/O.CMPMOSI - Reserved for future use. Use these pins as general-purpose I/O.CMPCLK - Reserved for future use. 阅读全文
posted @ 2013-08-03 19:16 IAmAProgrammer 阅读(672) 评论(0) 推荐(0) 编辑
摘要: http://www.altera.com/literature/hb/max2/max2_mii51009.pdfThe open-drain pin never drives high, only low or tri-state. When the open-drain pinis active, it drives low. When the open-drain pin is inactive, the pin is tri-stated and the trace pulls up to 5.0 V by the external resistor. The purpose of 阅读全文
posted @ 2013-07-29 11:17 IAmAProgrammer 阅读(1026) 评论(0) 推荐(0) 编辑
摘要: Connect a ARM Microcontroller to a FPGA using its Extended Memory Interface (EMI)http://elinux.org/Connect_a_ARM_Microcontroller_to_a_FPGA_using_its_Extended_Memory_Interface_(EMI)http://www.makestuff.eu/wordpress/software/fpgalink/http://www.techonlineindia.com/techonline/design_centers/170438/inte 阅读全文
posted @ 2013-07-28 23:24 IAmAProgrammer 阅读(694) 评论(0) 推荐(0) 编辑
摘要: http://www.ti.com/lit/ds/symlink/sn74lvc1g29.pdf 阅读全文
posted @ 2013-07-27 13:22 IAmAProgrammer 阅读(406) 评论(0) 推荐(0) 编辑
摘要: The SILICA Xynergy-M4 Board combines an ARM Cortex-M4 based STMicroelectronics STM32F417 controller with a Xilinx Spartan-6 low-cost FPGA (XC6SLX16) in one design.There are numerous development tools for either ARM Cortex-M microcontrollers or FPGA kits, but this is the first module in the market th 阅读全文
posted @ 2013-07-26 19:12 IAmAProgrammer 阅读(879) 评论(0) 推荐(0) 编辑
摘要: Key FeaturesHigh-performance FPGA configuration and PROM/CPLD programmingIncludes innovative FPGA-based acceleration firmware encapsulated in a small form factor pod attached to the cableSupports JTAG and Slave-Serial programming topologiesFirmware downloadable over cableEasy to useFully integrated 阅读全文
posted @ 2013-07-24 12:02 IAmAProgrammer 阅读(5268) 评论(0) 推荐(0) 编辑
摘要: XPROG-m编程器是为取代较早版本的XPROG编程器而设计的。XPROG-m编程器硬件完全与XPROG编程器向上兼容,还具有其它许多功能。该XPROG - M支持摩托罗拉68HC05,68HC08,68HC11,68HC(S)12,HC912,MC9S12,MC9S12X,德州仪器TMS370,M... 阅读全文
posted @ 2013-07-24 11:50 IAmAProgrammer 阅读(2776) 评论(0) 推荐(0) 编辑
摘要: http://bbs.ednchina.com/BLOG_ARTICLE_18577.HTM电感是储能元件,而磁珠是能量转换(消耗)器件。电感多用于电源滤波回路,侧重于抑止传导性干扰;磁珠多用于信号回路,主要用于EMI方面。磁珠用来吸收超高频信号,象一些RF电路,PLL,振荡电路,含超高频存储器电路(DDR,SDRAM,AMBUS等)都需要在电源输入部分加磁珠,而电感是一种储能元件,用在LC振荡电路、中低频的滤波电路等,其应用频率范围很少超过50MHz。1.片式电感:在电子设备的PCB板电路中会大量使用感性元件和EMI滤波器元件。这些元件包括片式电感和片式磁珠,以下就这两种器件的特点进行描述并 阅读全文
posted @ 2013-07-24 00:26 IAmAProgrammer 阅读(672) 评论(0) 推荐(0) 编辑
摘要: IC开短路测试(open_short_test),编程器测试接触不良、开短路用的该是这个原理http://kitebee.gnway.net/forum.php?mod=viewthread&tid=69654IC开短路测试(open_short_test)又叫continuity test 或contact test,它是一种非常快速发现芯片的各个引脚间的是否有短路,及在芯片封装时是否missing bond wires.通常都会被放测试程序的最前面.它还能发现测试时接触是否良好,探针卡或测试座是否有问题.开短路测试的测试原理比较简单,分open_short_to_VDD 测试和op 阅读全文
posted @ 2013-07-22 14:51 IAmAProgrammer 阅读(12593) 评论(0) 推荐(0) 编辑
摘要: http://www.ideyi.org/article/11-05/2575971305526398.html?sort=2068_2073_2092_0MP1593制作的DC-DC稳压电源,这款DC-DC稳压电源的体积很小,但它能提供2A 甚至最高达3A 的输出电流,并且其性能指标非常好,下面就... 阅读全文
posted @ 2013-07-22 10:58 IAmAProgrammer 阅读(1807) 评论(0) 推荐(0) 编辑
摘要: http://dangerousprototypes.com/docs/Bus_BlasterBus Blaster v2 is an experimental, high-speed JTAG debugger for ARM processors, FPGAs, CPLDs, flash, and more. Thanks to a reprogrammable buffer, a simple USB update makes Bus Blaster v2 compatible with many different JTAG debugger types in the most pop 阅读全文
posted @ 2013-07-18 12:18 IAmAProgrammer 阅读(1219) 评论(0) 推荐(0) 编辑
摘要: http://www.dzsc.com/data/html/2008-12-23/75397.htmlJTAG测试信号由下面5个信号组成。 TRST:测试复位输入信号,测试接口初始化 TCK:测试时钟,在TCK时钟的同步作用下,通过TDI和TDO引脚串行移入/移出数据或指令;同时,也为TAP(测试访问端口)控制器的状态机提供时钟。 TMS:测试模式选择信号,控制测试接口状态机的操作。 TDI:测试数据输入线,其串行输入数据至边界扫描寄存器或指令寄存器(由TAP控制器的当前状态及己保存在指令寄存器中的指令来控制)。 TDO:测试数据输出线,把从边界扫描链采样的数据传输至串行测试电路中的... 阅读全文
posted @ 2013-07-17 17:09 IAmAProgrammer 阅读(1162) 评论(0) 推荐(0) 编辑
摘要: http://www.amobbs.com/thread-3293203-1-1.html首先必须要了解电感的一些特性:电磁转换与磁储能.其它所有参数都是由这两个特性引出来的.电感回路通电瞬间断电瞬间相信有初中文化是坛友们都知道,一个电池对一个线圈通电,这是个电磁铁.不论你是否科盲,你一定会奇怪,这有什么值得分析的呢?有!我们要分析它通电和断电的瞬间发生了什么.线圈(以后叫作"电感"了)有一个特性---电磁转换,电可以变成磁,磁也可以变回电.当通电瞬间,电会变为磁并以磁的形式储存在电感内.而断电瞬磁会变成电,从电感中释放出来.现在我们看看下图,断电瞬间发生了什么:前面我说过 阅读全文
posted @ 2013-07-17 14:06 IAmAProgrammer 阅读(4061) 评论(0) 推荐(0) 编辑
摘要: http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1824&appnote=en011794In many applications, a DC/DC Converter is used to produce... 阅读全文
posted @ 2013-07-17 01:24 IAmAProgrammer 阅读(3044) 评论(0) 推荐(0) 编辑
摘要: http://analogtalk.com/?p=534http://analogtalk.com/?p=551Posted byAnalogAdvocateon April 09, 2010Design,GeneralIn today’s highly competitive electronics environment, designers are constantly looking for ways to reduce overall system costs. One of the most commonly asked questions that analog speciali 阅读全文
posted @ 2013-07-16 23:16 IAmAProgrammer 阅读(2341) 评论(0) 推荐(0) 编辑
摘要: http://www.edn.com/design/analog/4337128/Make-a-DAC-with-a-microcontroller-s-PWM-timerMany embedded-microcontroller applications require generation of analog signals. An integrated or stand-alone DAC fills the role. However, you can often use PWM signals for generating the required analog signals. Y 阅读全文
posted @ 2013-07-16 22:46 IAmAProgrammer 阅读(867) 评论(0) 推荐(0) 编辑
摘要: http://pdfserv.maximintegrated.com/en/an/AN818.pdfhttp://www.maximintegrated.com/app-notes/index.mvp/id/818Digital Adjustment of DC-DC Converter Output Voltage in Portable ApplicationsAbstract:This tutorial discusses methods for digitally adjusting the output voltage of a DC-DC converter. The digita 阅读全文
posted @ 2013-07-16 22:34 IAmAProgrammer 阅读(775) 评论(0) 推荐(0) 编辑
摘要: 随着FT232H USB2.0高速芯片的发布,英商飞特蒂亚公司(FTDI)进一步巩固了其在USB接口集成电路产品的地位。此款多功能的单通道USB转UART/FIFO接口设备可通过EEPROM配置为各种不同的串行或并行接口。与FTDI建设完备精良的USB设备驱动一起,这套方案使工程师可以轻松的将高速 USB连接引入新的和传统的外设设计中。另外,还有相关的UM232H评估模块帮助工程师快速建立设计样机,测试FT232H集成到新的系统设计的适用性。其高度集成的USB设备控制器包含USB, 串行和并行协议引擎,而不需要开发USB专用固件。设备支持3.3V的IO接口电平,允许5V输入,使之适用于连接各种 阅读全文
posted @ 2013-07-16 22:20 IAmAProgrammer 阅读(19659) 评论(0) 推荐(0) 编辑
摘要: http://www.360doc.com/content/10/1102/16/2285160_66006645.shtmlRail to rail: 轨至轨,指器件的输入输出电压范围可以达到电源电压。 传统的模拟集成器件,如运放、A/D、D/A等,其模拟引脚的电压范围一般都达不到电源,以运放为例,电源为+/-15V的运放,为确保性能(首先是不损坏,其次是不反相,最后是足够的共模抑制比),输入范围一般不要超过+/-10V,常温下也不要超过+/-12V;输出范围,负载10kohm时一般只有+/-11V,小负载电阻(600ohm)时只能保证+/-10V。这对器件的应用带来很多不便。 rail.. 阅读全文
posted @ 2013-07-16 20:29 IAmAProgrammer 阅读(4720) 评论(0) 推荐(0) 编辑
摘要: TLC2262和TLC2264分别是TI公司双路和四路运算放大器,两种器件可以在单电源或双电源条件下供电,从而增强了动态的范围,可以达到轨对轨输出的性能。TLC226X系列与TLC225X的微功耗和TLC227X的交流性能方面兼容。它可在电池供电时消耗较低的电源电流,而仍然具有足够好的交流性能。噪声性能已经较以前生产的CMOS放大器具有显著的改进。每个放大器的电源电流只有200μA(典型值)。 TLC226x系列放大器,具有较高的输入阻抗和非常低的噪声,适合于高阻抗源的小信号调节,例如压电转感器。由于它的微功耗,使该器件非常适合于手持式监控和远距离感应的设备,另外增加了轨对轨输出的功能,致使该 阅读全文
posted @ 2013-07-16 20:18 IAmAProgrammer 阅读(5367) 评论(0) 推荐(0) 编辑
摘要: LM358里面包括有两个高增益、独立的、内部频率补偿的双运放,适用于电压范围很宽的单电源,而且也适用于双电源工作方式,它的应用范围包括传感放大器、直流增益模块和其他所有可用单电源供电的使用运放的地方使用。LM358封装有塑封8引线双列直插式和贴片式两种。LM358的特点:. 内部频率补偿. 低输入偏流. 低输入失调电压和失调电流. 共模输入电压范围宽,包括接地. 差模输入电压范围宽,等于电源电压范围. 直流电压增益高(约100dB). 单位增益频带宽(约1MHz). 电源电压范围宽:单电源(3—30V);. 双电源(±1.5 一±15V). 低功耗电流,适合于电池供电. 输 阅读全文
posted @ 2013-07-16 20:15 IAmAProgrammer 阅读(5260) 评论(0) 推荐(0) 编辑
摘要: http://www.freelabs.com/~whitis/electronics/jtag/One of the big issues in making a JTAG pod is level translation. The state of level translation ICs leaves a LOT to be desired. You would think that there would be a lot of chips that you could apply 1.2-5V power and logic on port A and 1.2-5V (or 0V) 阅读全文
posted @ 2013-07-16 15:48 IAmAProgrammer 阅读(904) 评论(0) 推荐(0) 编辑
摘要: http://www.ethernut.de/en/hardware/turtelizer/Introducing Turtelizer 2OverviewTurtelizer 2 had been developed to provide JTAG Flash programming and debugging of ARM based boards via USB. Typical target boards areEthernut 3, theElektor Internet RadioorEthernut 5. However, as the hardware is based on 阅读全文
posted @ 2013-07-16 15:17 IAmAProgrammer 阅读(1713) 评论(0) 推荐(0) 编辑
摘要: http://www.sigrok.org/wiki/Main_PageThesigrokproject aims at creating aportable, cross-platform, Free/Libre/Open-Source signal analysis software suitethat supports various device types, such aslogic analyzers,MSOs,oscilloscopes,multimeters,LCR meters,sound level meters,thermometers,hygrometers,anemo 阅读全文
posted @ 2013-07-15 18:26 IAmAProgrammer 阅读(649) 评论(0) 推荐(0) 编辑
摘要: http://www.willar.com/article/article_view.asp?id=463由DC-DC变换集成电路MC34063组成,34063 广泛应用于于DC-DC的电源转换电路中,本电路中的34063 接成升压电路形式,将5V电压升压到12-14.5V,得到编程所需的Vpp电压,R8、R9、R10组成电压取样电路。R11和Q1组成14V VPP电压切换电路Vout(输出电压)=1.25V(1+R2/R1)= 1.25V * ( (R1+R2) / R1 )R1=R10+R9=0.56K + 1.8K=2.36KR2=R8=20KVout = 1.25 * ( ( 2.36 阅读全文
posted @ 2013-07-15 14:28 IAmAProgrammer 阅读(948) 评论(0) 推荐(0) 编辑
摘要: 阅读全文
posted @ 2013-07-15 13:15 IAmAProgrammer 阅读(1718) 评论(0) 推荐(0) 编辑
摘要: Voltage Translation for Analog to Digital Interface ADChttp://openschemes.com/2010/03/23/zeroplus-logic-cube-review-and-teardown/LAP 16032 has 4.5MBIT... 阅读全文
posted @ 2013-07-15 13:11 IAmAProgrammer 阅读(4868) 评论(0) 推荐(0) 编辑
摘要: http://www.faludi.com/bwsn/xbee-level-shifting/The XBee communication (RX/TX) pins definitelyoperateoff of a 5V signal with the Arduino. We’ve seen this a lot and done this a lot, and it certainly keeps things simple. That said, there’s nothing wrong with adding a level-shifting circuit to deliver 3 阅读全文
posted @ 2013-07-15 12:21 IAmAProgrammer 阅读(8106) 评论(0) 推荐(0) 编辑
摘要: http://www.daycounter.com/Circuits/Level-Translators/Level-Translators.phtmlInterfacing 5V and 3V logic circuits is a common task. 3V logic is preferred to 5V logic because it consumes less power, so most microcontrollers and peripheral devices use the lower voltage logic. However, it is often the c 阅读全文
posted @ 2013-07-15 12:04 IAmAProgrammer 阅读(558) 评论(0) 推荐(0) 编辑
摘要: http://www.daycounter.com/Circuits/Short-Circuit-Protection/Short-Circuit-Protection.phtmlShort circuit protection is often a desirable feature to add to power amplifiers or power supplies, for both safety concerns and protection of circuitry.The circuit in the schematic below can be used to protect 阅读全文
posted @ 2013-07-15 12:01 IAmAProgrammer 阅读(849) 评论(0) 推荐(0) 编辑
摘要: http://electronicdesign.com/boards/non-inverting-level-shifter-requires-only-one-op-amp-one-supply-voltageWith portable battery-operated devices continuing to add functionality while shrinking in size, printed-circuit-board real estate becomes increasingly valuable. Single-supply circuitry can help 阅读全文
posted @ 2013-07-15 11:57 IAmAProgrammer 阅读(11292) 评论(0) 推荐(0) 编辑
摘要: SN7407Convert TTL Voltage Levels to MOS LevelsHigh Sink-Current CapabilityInput Clamping Diodes Simplify SystemDesignOpen-Collector Driver for Indicator Lampsand RelaysInputs Fully Compatible With Most TTLCircuitsThese TTL hex buffers/drivers featurehigh-voltage open-collector outputs for interfacin 阅读全文
posted @ 2013-07-15 02:47 IAmAProgrammer 阅读(1804) 评论(0) 推荐(0) 编辑
摘要: http://debugmo.de/2012/02/xvcd-the-xilinx-virtual-cable-daemon/I recently discovered an almost undocumented function in Xilinx ISE: the Xilinx virtual cable driver. It’s basically “a platform cable without a platform cable” (asmarcansaid so nicely) – it allows you use Impact (and Chipscope, and all 阅读全文
posted @ 2013-07-15 01:24 IAmAProgrammer 阅读(9609) 评论(0) 推荐(0) 编辑
摘要: 74HC125; 74HCT125Quad buffer/line driver; 3-stateThe 74HC125; 74HCT125 is a quad buffer/line driver with 3-state outputs controlled by the output enable inputs (nOE). A HIGH on nOE causes the outputs to assume a high impedance OFF-state. Inputs include clamp diodes. This enables the use of current l 阅读全文
posted @ 2013-07-15 00:44 IAmAProgrammer 阅读(1297) 评论(0) 推荐(0) 编辑
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