ets gre 数学考试讲义， Mathematical Conventions for the Quantutative Reasoning Measure of the GRE revised General Test for the Quantitative Reasoning Measure of the GRE® revised General Test
标签： gre
上传时间： 2021-09-07
上传用户：zghflxj
LAN9254 + SAME54 MCU 从站设计•1.支持2/3个port口的EtherCat Slave控制器，并内置有8个FMMU 和8个SyncManagers; 并有8KB的更大的DPRAM存储资源；•2. 8/16bit总线，支持和大多数8/16bit以及32bit的host MCU通讯； •3. 内部集成了支持HP Auto-MDIX的以太网PHY芯片； •4. 支持Wake on Lan以太网远程唤醒技术；兼容EtherCat P协议； •5. 具有低功耗工作模式，可以允许系统进入睡眠模式以节省更多功耗，直到被Master访问； •6. 支持线缆诊断技术； •7. 支持1.8V~3.3V的灵活可变的IO电压，省去需要外加Voltage shifter芯片的成本； •8. 多功能GPIO，可以配置为Local Bus，SPI, PWM，通用GPIO等多种接口功能； •9. 工业级温度范围，最高可以支持105度工业温度要求；
标签： mcu lan9254 ethercat从站
上传时间： 2021-11-09
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C10018_RTL8201CP-VD-LF_2012-11-22.PDFSINGLE-CHIP/SINGLE-PORT 10/100M FAST ETHERNET PHYCEIVER (With Auto Crossover) DATASHEET
标签： rtl8201cp
上传时间： 2022-01-13
上传用户：xsr1983
The PW2606B is a front-end over voltage and over current protection device. It achieves wide inputvoltage range from 2.5VDC to 40VDC. The over voltage threshold can be programmed externally orset to internal default setting. The low resistance of integrated power path nFET switch ensures betterperformance for battery charging system applications. It can deliver up to 1A current to satisfy thebattery supply system. It integrates the over-temperature protection shutdown and auto-recoverycircuit with hysteresis to protect against over current events
标签： pw2606b
上传时间： 2022-02-11
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The PW2228A is a high efficiency single inductor Buck-Boost converter which can supply theload current up to 1.5A. It provides auto-transition between Buck and Boost Mode. The PW2228Aoperates at 2.4MHz switching frequency in CCM. DC/DC converter operates at Pulse-Skipping Modeat light load. The output voltage is programmable using an external resistor divider, or is fixed to3.3V internally. The load is disconnected from the VIN during shutdown.The PW2228A is available in TDFN3X3-10 package.
标签： pw2228a
上传时间： 2022-02-11
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Agilent 34401A Service Guide.pdfIEC Measurement Category II includes electrical devices connected to mains at an outlet on a branch circuit. Such devices include most small appliances, test equipment, and other devices that plug into a branch outlet or socket. The 34401A may be used to make measurements with the HI and LO inputs connected to mains in such devices, or to the branch outlet itself (up to 300 VAC). However, the 34401A may not be used with its HI and LO inputs connected to mains in permanently installed electrical devices such as the main circuit-breaker panel, sub-panel disconnect boxes, or permanently wired motors. Such devices and circuits are subject to overvoltages that may exceed the protection limits of the 34401A. Note: Voltages above 300 VAC may be measured only in circuits that are isolated from mains. However, transient overvoltages are also present on circuits that are isolated from mains. The Agilent 34401A are designed to safely withstand occasional transient overvoltages up to 2500 Vpk. Do not use this equipment to measure circuits where transient overvoltages could exceed this level. Additional Notices Waste Electrical and Electronic Equipment (WEEE) Directive 2002/96/EC This product complies with the WEEE Directive (2002/96/EC) marking requirement. The affixed product label (see below) indicates that you must not discard this electrical/electronic product in domestic household waste. Product Category: With reference to the equipment types in the WEEE directive Annex 1, this product is classified as a "Monitoring and Control instrumentation" product. Do not dispose in domestic household waste. To return unwanted products, contact your local Agilent office, or see www.agilent.com/environment/product for more information. Agilent 34138A Test Lead Set The Agilent 34401A is compatible with the Agilent 34138A Test Lead Set described below. Test Lead Ratings Test Leads - 1000V, 15A Fine Tip Probe Attachments - 300V, 3A Mini Grabber Attachment - 300V, 3A SMT Grabber Attachments - 300V, 3A Operation The Fine Tip, Mini Grabber, and SMT Grabber attachments plug onto the probe end of the Test Leads. Maintenance If any portion of the Test Lead Set is worn or damaged, do not use. Replace with a new Agilent 3413
标签： agilent
上传时间： 2022-02-20
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首先下载软件，解压软件，安装在程序中找到SEGGER,选里面的J-FLASH，进入界面，刚开始的那个界面可以忽略，不用建project也可以；单击菜单栏的“Options---Project settings”打开设置，进行jlink配置;正在General选项，选择“USB”，一般都是默认配置，确认一下即可;然后在CPU选项，选择芯片型号，先选择“Device”才能选择芯片型号，芯片型号，要根据你使用的芯片进行选择;在Target interface选项 里面选择SWD模式;首先Target里面选“Connection”连接目标芯片，然后 Target--Auto进行程序烧写;首先Target里面选择“Connection”连接目标芯片，然后 Target--Auto进行程序烧写.SEGGER J-Links are the most widely used line of debug probes available today. They've proven their value for more than 10 years in embedded development. This popularity stems from the unparalleled performance, extensive feature set, large number of supported CPUs, and compatibility with all popular development environments.
标签： JLINK
上传时间： 2022-03-22
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本系统采用电动机电枢供电回路串接采样电阻的方式来实现对小型直流有刷电动机的转速测量。该系统主要由二阶低通滤波电路,小信号放大电路、单片机测量显示电路、开关稳压电源电路等组成。同时自制电机测速装置,用高频磁环作为载体,用线圈绕制磁环,利用电磁感应原理检测电机运行时的漏磁,将变化的磁场信号转化为磁环上的感应电流。用信号处理单元电路将微弱电信号转化为脉冲信号,送由单片机检测,从而达到准确测量电机的速度的要求。In this system, the sampling resistance of armature power supply circuit is connected in series to measure the speed of small DC brush motor. The system is mainly composed of second-order low-pass filter circuit, small signal amplifier circuit, single-chip measurement and display circuit, switching regulated power supply circuit and so on. At the same time, the self-made motor speed measuring device uses high frequency magnetic ring as the carrier, coil winding magnetic ring, and electromagnetic induction principle to detect the leakage of magnetic field during the operation of the motor, which converts the changed magnetic field signal into the induced current on the magnetic ring. The weak electric signal is transformed into pulse signal by signal processing unit circuit, which is sent to single chip computer for detection, so as to meet the requirement of accurate measurement of motor speed.
标签： 直流电动机
上传时间： 2022-03-26
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数字示波器功能强大,使用方便,但是价格相对昂贵。本文以Ti的MSP430F5529为主控器,以Altera公司的EP2C5T144C8 FPGA器件为逻辑控制部件设计数字示波器。模拟信号经程控放大、整形电路后形成方波信号送至FPGA测频,根据频率值选择采用片上及片外高速AD分段采样。FPGA控制片外AD采样并将数据输入到FIFO模块中缓存,由单片机进行频谱分析。测试表明:简易示波器可以实现自动选档、多采样率采样、高精度测频及频谱分析等功能。Digital oscilloscope is powerful and easy to use, but also expensive. The research group designed a low-cost digital oscilloscope, the chip of MSP430F5529 of TI is chosen as the main controller and the device of EP2C5T144C8 of Altera company is used as the logic control unit. Analog signal enter the programmable amplifier circuit, shaping circuit and other pre-processing circuit. The shaped rectangular wave signal is sent to FPGA for measure the frequency. According to the frequency value to select AD on-chip or off-chip high-speed AD for sampling. FPGA controls the off-chip AD sampling and buffers AD data by FIFO module. The single chip microcomputer receives the data, and do FFT for spectrum analysis. The test shows that the simple oscilloscope can realize automatic gain selection, sampling at different sampling rates, high precision frequency measurement and spectrum analysis.
上传时间： 2022-03-27
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电学中的测量技术涉及范围非常广,电流测量在电学计量中占有非常重要的位置。如何精确地进行电流测量是精密测量的一大难题。传统的电流检测电路多采用运算放大芯片与片外电流检测电路相结合的方式,电路集成度很低,需要较多的接口和资源才能完成对电路的检测。本文把所有电路部分都集成在一块芯片上,包括检测电阻,运算放大器电路及模拟转数字转换电路,从而在电路内部可以进行电流检测,使电路更好的集成化。前置电路使用二级共源共栅结构的运算放大器,减小沟道长度调制效应造成的电流误差。10位SAR ADC中采用电容驱动能力强的传输门保证了模数转化器的有效精度。比较器模块采用再生锁存器与迟滞比较器作为基础单元组合解决精密测量的问题。本设计可以作为嵌入芯片内的一小部分而检测芯片中的微小电流1mA~100mA,工作电压在1.8v左右,电流检测精度预期达到10uA的需求。The measurement technology in electricity involves a wide range,and current measurement plays a very important position in electrical measurement.How to accurately measure current is a big problem in precision measurement. The traditional current detecting circuit adopts the combination of the operational amplifier chip and theoff-chip current detecting circuit, The circuit integration is very low, and more interfaces and resources are needed tocomplete the circuit detection.This topic integrates all the circuit parts into one chip, including detection resistance, operational amplifier circuit andanalog to digital conversion circuit. Highly integrated circuit makes the external resources on the chip more intensive,so that current detection can be carried out inside the circuit, so that the circuit can be better integrated. Thefront-end circuit of this project uses two-stage cascade operational amplifier and cascade tube to reduce the currenterror caused by channel length modulation effect. In 10-bit SAR ADC, the transmission gate with strong capacitivedriving ability ensures the effective accuracy of the analog-to-digital converter. Comparator module uses regenerativelatch and hysteresis comparator as basic unit to solve the difficult problem of precision measurement. This topic can beused as a small part of the embedded chip to detect the micro-current in the chip 1 mA~100 mA, the working voltageis about 1.8v, and the current detection accuracy is expected to reach the requirement of 10 uA.
上传时间： 2022-04-03
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