Piezoelectric motors are used in digital cameras for autofocus,zooming and optical image stabilization. Theyare relatively small, lightweight and effi cient, but theyalso require a complicated driving scheme. Traditionally,this challenge has been met with the use ofseparatecircuits, including a step-up converter and an oversizedgeneric full-bridge drive IC. The resulting high componentcount and large board space are especially problematicin the design of cameras for ever shrinking cell phones.The LT®3572 solves these problems by combining astep-up regulator and a dual full-bridge driver in a 4mm× 4mm QFN package. Figure 1 shows a typical LT3572Piezo motor drive circuit. A step-up converter is usedto generate 30V from a low voltage power source suchas a Li-Ion battery or any input power source within thepart’s wide input voltage range of 2.7V to 10V. The highoutput voltage of the step-up converter, adjustable upto 40V, is available for the drivers at the VOUT pin. Thedrivers operate in a full-bridge fashion, where the OUTAand OUTB pins are the same polarity as the PWMA andPWMB pins, respectively, and the OUTA and OUTB pinsare inverted from PWMA and PWMB, respectively. Thestep-up converter and both Piezo drivers have their ownshutdown control. Figure 2 shows a typical layout
上传时间： 2013-11-18
上传用户：hulee
Avalanche photodiodes (APDs) are widely utilized in laserbased fiberoptic systems to convert optical data intoelectrical form. The APD is usually packaged with a signalconditioning amplifier in a small module. An APD receivermodule and attendant circuitry appears in Figure 1. TheAPD module (figure right) contains the APD and a transimpedance(e.g., current-to-voltage) amplifier. An opticalport permits interfacing fiberoptic cable to the APD’sphotosensitive portion. The module’s compact constructionfacilitates a direct, low loss connection between theAPD and the amplifier, necessary because of the extremelyhigh speed data rates involved
上传时间： 2013-10-25
上传用户：brain kung
为解决直流逆变交流的问题，有效地利用能源，让电源输出最大功率，设计了高性能的基于IR2101最大功率跟踪逆变器，并以SPMC75F2413A单片机作为主控制器。高电压、高速功率的MOSFET或IGBT驱动器IR2101采用高度集成的电平转换技术，同时上管采用外部自举电容上电，能够稳定高效地驱动MOS管。该逆变器可以实现DC/AC的转换，最大功率点的跟踪等功能。实际测试结果表明，该逆变器系统具有跟踪能力强，稳定性高，反应灵敏等特点，该逆变器不仅可应用于普通的电源逆变系统，而且可应用于光伏并网发电的逆变系统，具有广泛的市场前景。 Abstract: To solve the problem of DC-AC inverter， and to utilize solar energy more efficiently， the design of maximum power point tracking inverter based on IR2101 was achieved with a high-performance， which can make the system output power maximum. SPMC75F2413A was adopted as main controller. IR2101 is a high voltage， high speed power MOSFET and IGBT driver. It adopted highly integrated voltage level transforming technology， and an external bootstrap capacitor was used， which could drive MOS tube efficiently and stably. Many functions are achieved in the system， such as DC/AC conversion， maximun power point tracking， etc. The actual test result shows that the inverter system has characteristics of strong tracking ability， high stability and reacting quickly. The design can not only be used in ordinary power inverter system， but also be used in photovoltaic power inverter system. The design has certain marketing prospects
上传时间： 2013-11-17
上传用户：lliuhhui
Permission to make digital or hard copies of all or part of this work forpersonal or classroom use is granted without fee provided that copies arenot made or distributed for profit or commercial advantage and that copiesbear this notice and the full citation on the first page. To copy otherwise, torepublish, to post on servers or to redistribute to lists, requires prior specificpermission.
标签： 数字电源
上传时间： 2013-10-16
上传用户：dddddd
Features: High efficiency, high reliability, low cost AC input range selected by switch 100% full load burn-in test Protections: Short circuit / Over load Fixed switching frequency at 25KHz Cooling by free air convection 1 year warranty Dimensions: 199*98*38mm (L*W*H)
标签： Switchin Output Single SKS
上传时间： 2013-10-30
上传用户：taa123456
Keil C51是美国Keil Software公司出品的51系列兼容单片机C语言软件开发系统，与汇编相比，C语言在功能上、结构性、可读性、可维护性上有明显的优势，因而易学易用。Keil提供了包括C编译器、宏汇编、连接器、库管理和一个功能强大的仿真调试器等在内的完整开发方案，通过一个集成开发环境（uVision）将这些部分组合在一起。运行Keil软件需要WIN98、NT、WIN2000、WINXP等操作系统。如果你使用C语言编程，那么Keil几乎就是你的不二之选，即使不使用C语言而仅用汇编语言编程，其方便易用的集成环境、强大的软件仿真调试工具也会令你事半功倍。 解压缩以后安装，步骤如下： 1.打开up51v706a.txt(本文件)记下安装序列号。进入setup目录点击setup.exe进行安装； 2.选择Install Support....全新安装，以前没有安装过或者放弃以前的序列号安装; 选择Update Current Installation升级安装，将可以保持原来的序列号，不必再次输入 3.选择Full安装，Next->Yes(接受版权信息)->选择安装目录->Next->输入序列号、姓名、公司 等，除了序列号以外，都随意，可以如实输入你的姓名等。->next-> ....直到安装完成。 注意： 1.每次安装都必须进行这几步，每次都需要重新写入AddOn标识； 2.假如安装过程中存在病毒防火墙，可能会产生xcopy错误使安装失败，此时请先 关闭病毒防火墙，然后再安装; 3.安装前必须退出正在运行的Keil软件，否则也会产生xcopy错误使安装失败； 4.安装过程中可能会出现安装Secrity Key错误，点击确定即可。 这组安装码可以使用keil C51软件到2033年12月底，够用了吧。 Ident = Y1DZKM (这个号码已经输入在addon目录下的文件中，你不必理会了) SN = K1DZP-5IUSH-A01UE *************************************** 0xfd汉字补丁已经预先处理。安装以后可以打开工程\keil\c51\examples\0xfd\ee.uv2检验
上传时间： 2013-10-18
上传用户：takako_yang
数字控制的交流调速系统所选用的微处理器、功率器件及产生PWM波的方法是影响交流调速系统性能好坏的直接因素。在介绍了正弦脉宽调制(SPWM)技术的基础上，设计了一种以8098单片机作为控制器，以智能功率模块IPM为开关器件的变频调速系统。通过软件编程，产生正弦脉冲宽度调制波形来控制绝缘栅双极晶体管的导通和关断，从而达到控制异步电动机转速的目的。实验结果表明，该系统可调频率调电压，稳定度高，调速范围宽，具有较强的实用价值 Abstract: AC variable speed with digital control systems used microprocessors， power devices and generate PWM wave is the direct factors of affecting the performance AC speed regulation system. On the basis of introducing the sinusoidal pulse width modulation (SPWM) technology，this paper designed variable speed system which used 8098 as a controller， intelligent power module IPM as switching device. Through software programming， resulting in sinusoidal pulse width modulation waveform to control the insulated gate bipolar transistor turn on and off， so as to achieve the purpose of speed control of induction motors. Experimental results show that the system can adjust frequency modulation voltage， high stability， wide speed range， has a strong practical value.
上传时间： 2013-11-14
上传用户：ynwbosss
HIGH SPEED 8051 μC CORE - Pipe-lined Instruction Architecture; Executes 70% of Instructions in 1 or 2 System Clocks - Up to 25MIPS Throughput with 25MHz System Clock - 22 Vectored Interrupt Sources MEMORY - 4352 Bytes Internal Data RAM (256 + 4k) - 64k Bytes In-System Programmable FLASH Program Memory - External Parallel Data Memory Interface – up to 5Mbytes/sec DIGITAL PERIPHERALS - 64 Port I/O; All are 5V tolerant - Hardware SMBusTM (I2CTM Compatible), SPITM, and Two UART Serial Ports Available Concurrently - Programmable 16-bit Counter/Timer Array with 5 Capture/Compare Modules - 5 General Purpose 16-bit Counter/Timers - Dedicated Watch-Dog Timer; Bi-directional Reset CLOCK SOURCES - Internal Programmable Oscillator: 2-to-16MHz - External Oscillator: Crystal, RC, C, or Clock - Real-Time Clock Mode using Timer 3 or PCA SUPPLY VOLTAGE ........................ 2.7V to 3.6V - Typical Operating Current: 10mA @ 25MHz - Multiple Power Saving Sleep and Shutdown Modes 100-Pin TQFP (64-Pin Version Available) Temperature Range: –40°C to +85°C
标签： C8051F020
上传时间： 2013-10-12
上传用户：lalalal
为解决电致变色器件的颜色变化受外界环境颜色控制的问题，设计了一种基于单片机的便携式颜色自适应识别电路。与传统颜色识别电路相比较，该电路利用数字式的颜色传感器来获取外界环境颜色，产生的数字颜色信号易于单片机进行处理。在电路中，下位机部分主要负责获取电致变色器件变色参数及控制电致变色器件的颜色变化;而上位机部分主要负责把下位机获取的电致变色器件变色参数进行电压到颜色的曲线拟合，并通过蓝牙通信把拟合曲线参数传递给下位机。结果表明，该电路能自动根据环境颜色提供-4~4 V范围步进为0.1 V的电压来驱动电致变色器件的颜色显示，与传统的颜色识别电路设计相比，识别的精度和速度都得到了明显改善。 Abstract: In this paper， a portable adaptive circuit for color identification(PACCI) based on MCU was designed. Compared to the traditional color identification circuit， the PACCI adopts digital sensor to detect the color data from external environment and further generate digital color data， which can be processed easily by MCU. In PACCI， the slave is mainly responsible for detecting the color parameters of the corresponding elcreochromic device and further driving it. For the master， which is mainly responsible for the color curve fitting based on the parameters of the electrochromic device， and transmits the fitting parameters to the slave through the bluetooth device. The results show that the PACCI can provide the basis voltage range from -4V to 4V automatically based on the colors of external environment with step as 0.1V to drive the corresponding electrochromic device. Compared to the traditional color recognition circuit， the recognition accuracy and speed of PACCI have been improved significantly.
上传时间： 2013-11-09
上传用户：franktu
为提高太阳能的利用率，以ATmega8单片机为控制核心，设计了一套光电跟踪与视日运动轨迹跟踪互补控制的双轴太阳跟踪器。该跟踪器在晴天时，利用光敏电阻采集光强判断太阳位置,控制步进电机实现光电跟踪；在阴天时，采集时钟器件PCF8583的时间信息,计算当前太阳位置来实现视日运动轨迹跟踪。实验表明：该太阳跟踪器能在不同天气状况下对太阳进行较准确地跟踪，能量接收效率提高了30%，达到充分利用太阳能的目的。 Abstract: To improve the utilization rate of solar energy，a kind of solar tracking controller which effectively combined the sun angle tracking and photo electric tracking based on ATmega8is designed.In the sunny days，the solar tracking con-troller determines the sun's position by using photosensitive resistances to collect light intensity and control stepper motors to achieve photo electric tracking，n cloudy days，it collects clock chip PCF8583time information to calculate the current position of the sun and achieve the sun angle tracking.Experimental results show the solar tracking controller accurately tracks the sun in different weather conditions，improves received energy efficiency by30%and reaches the purpose of full use of solar energy.
上传时间： 2013-10-15
上传用户：urgdil
