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  • 电子书-RTL Design Style Guide for Verilog HDL540页

    电子书-RTL Design Style Guide for Verilog HDL540页A FF having a fixed input value is generated from the description in the upper portion of Example 2-21. In this case, ’0’ is output when the reset signal is asynchronously input, and ’1’ is output when the START signal rises. Therefore, the FF data input is fixed at the power supply, since the typical value ’1’ is output following the rise of the START signal. When FF input values are fixed, the fixed inputs become untestable and the fault detection rate drops. When implementing a scan design and converting to a scan FF, the scan may not be executed properl not be executed properly, so such descriptions , so such descriptions are not are not recommended. recommended.[1] As in the lower part of Example 2-21, be sure to construct a synchronous type of circuit and ensure that the clock signal is input to the clock pin of the FF. Other than the sample shown in Example 2-21, there are situations where for certain control signals, those that had been switched due to the conditions of an external input will no longer need to be switched, leaving only a FF. If logic exists in a lower level and a fixed value is input from an upper level, the input value of the FF may also end up being fixed as the result of optimization with logic synthesis tools. In a situation like this, while perhaps difficult to completely eliminate, the problem should be avoided as much as possible.

    标签: RTL verilog hdl

    上传时间: 2022-03-21

    上传用户:canderile

  • 基于LabVIEW和单片机的自动控制系统综合实验

    设计了自动控制系统综合实验案例“基于LabVIEW和单片机的温度控制系统设计”。实验系统硬件部分由单片机、温度传感器、D/A转换模块、调压模块和电烤箱组成,设计了单片机与各个模块之间的接口电路。软件部分采用LabVIEW软件实现控制算法,并设计监控界面实现参数设定、温度数据实时监控等功能。设计了单片机与LabVIEW软件之间的串口通信程序,实现了输入、输出数据的传输。通过综合实验系统设计,使学生得到控制系统设计和实验调试等综合能力的训练。A comprehensive experimental case of the automatic control system is presented,which is the design of the temperature control system based on LabVIEW and SCM.The hardware part of the experimental system is composed of the SCM,temperature sensor,D/A conversion module,voltage regulating module and electric oven.The interface circuit between the SCM and each module is designed.In the software part,LabVIEW software is used to realize the control algorithm,and the monitoring interface is designed to realize the functions of parameter setting,temperature data real-time monitoring,etc.The serial communication program between the SCM and LabVIEW software is designed to realize the transmission of input and output data.Through the design of this comprehensive experimental system,students can get the comprehensive ability training for the control system design,experiment debugging,etc.

    标签: labview 单片机 自动控制系统

    上传时间: 2022-03-27

    上传用户:qdxqdxqdxqdx

  • 基于STC12C5A60S2单片机的LED线阵显示装置

    LED 线阵显示装置, 分为 LED 线性旋转显示主机和图文录入器两部分。主机用直流电机带动由红绿 LED 组成的线阵旋转, 同时线阵按照时序依次切换显示状态, 在固定区域利用视觉暂留效果形成 16×16 点阵, 用以显示图文;图文录入器用 HMI 触控屏作为人机交互界面, 实现图文录入和回放功能。主机与图文录入器通过无线通信方式进行信息交互,可由图文录入器控制主机切换不同工作任务, 以及改变线阵显示内容。The LED linear array display device is divided into two parts:the one is the main unit used to display content,and the other one is used to input the contents.The main unit is driven by a DC motor to rotate the linear array composed by red and green light emitting diodes.At the same time,the 16×16 dot matrix that switching the display state according to the time sequence on the main unit displays pictures and texts in the fixed area,by using the visual temporary effect.The HMI touch screen is used as human machine interface to realize the function that input and playback pictures and texts.The two parts of the device communicate with each other through wireless communication.The image and text input controller can control the main unit to switch different tasks and change the content of linear array displayed.

    标签: stc12c5a60s2 单片机 led

    上传时间: 2022-03-28

    上传用户:jiabin

  • Qi无线充电原理

    近距电能传输——高效安全近距电能传输一般基于电磁感应原理进行。在此技术基础上,当接收器邻近发射器时才会进行电能传输。电磁感应技术的历史长达百年,多年米一直应用于各类电子产品中—如此普及全因其简单、高效以及安全技术概览以下将为你简要介绍无线电能传输技术。System Overview(Communication)Receiver sends messagesTo provide control information to the transmitterBy load modulation on the power signaTransmitter receives messagesTo receive control information frorn the recelverBy de-modulation of the reflected loadPower Pick Up( Receiver)Secondary coil (L Serial resonance capacitor (C) for efficient power transfer Parallel resonance capacitor(C, )for detection purposes Rectifier: full bridge(diode, or switched)+ capacitor Output switch for(dis)connecting the loadReceiver modulates load by Switching modulation resistor(R,n),or Switching modulation capacitor(Ca)Transmitter de-modulates reflected load by Sensing pnmary coil curent (p)and/o Sensing primary coil voltage (V,

    标签: qi 无线充电

    上传时间: 2022-03-31

    上传用户:

  • 915MHz超高频RFID阅读器射频前端电路设计

    为了提高超高频RFID系统中阅读器在低信噪比的情况下仍具有较高的识别能力,提出一种基于FPGA系统结合软件无线电方法实现超高频RFID射频前端电路方案。超高频射频识别系统必须符合EPC Class 1generation 2标准,所设计的电路系统以Xilinx公司的XC6SLX16-2CSG324FPGA芯片为硬件基础,将数字基带调制解调和中频滤波电路在FPGA系统中设计实现,重点阐述了射频前端电路的设计结构、AD/DA转换电路,以及数字滤波器的设计。实验结果表明,所设计的超高频RFID阅读器简化了前端电路系统结构,提升了稳定性,增强了抗干扰能力。该电路系统在信噪比较低的情况下,能够较好地实现915MHz频率的射频接收和发送。In order to improve the reader UHF RFID system still has a higher ability to identify,in the case of low signal-to-noise ratio.The UHF RFID systems must comply with EPC Class 1 generation 2 standard.In this paper,the design of the circuit system based on Xilinx's XC6SLX16-2CSG324 FPGA chip,and presents UHF RFID RF front-end circuit with software radio based on FPGA system.Digital baseband modem and IF filter circuit is designed and implemented in the FPGA system,and focused on designing the structure of the RF front-end circuit,AD/DA conversion circuits,and digital filter.Experimental results show that the UHF RFID reader de...

    标签: 915mhz 超高频 rfid 阅读 射频 前端 电路 设计

    上传时间: 2022-04-17

    上传用户:shjgzh

  • 基于TMS320F28335的超声波流量计硬件原理图+软件源码

    基于TMS320F28335的超声波流量计硬件原理图+软件源码本文以TMS320F28335 处理器为核心,设计一种用于管道流量测量的超声波流量计。系统硬件由核心板,超声波发射和接收电路,切换电路,超声换能器,基于ADS805 的高速信号采集电路,人机交互以及电源等模块构成。采用时差法进行管道流量测量,时差测量采用SCOT 加权的广义互相关时延估计算法。本论文设计的超声波流量计具有测量速度快、准确性好、成本低等优点。关键字:C2000,超声波,流量,广义互相关算法AbstractA kind of ultrasonic flowmeter using for the pipe flow measurement is designed based onTMS320F28335 in this paper. The system hardware consists of the following parts: the core board,ultrasonic signal transmitter and receiver circuits, switch circuit, ultrasonic transducer, signalacquisition circuit based on ADS805, human-computer interaction module and power supplymodule, etc. The system use the method of time difference for pipeline flow measurement and thetime difference is calculated by the time-delay algorithm of SCOT weighted generalizedcross-correlation. The ultrasonic flowmeter has the features of high testing speed, high precisionand low cost, etc.Keywords: C2000,Ultrasonic, Flow, Generalized Cross-Correlation Algorithm

    标签: tms320f28335 超声波流量计

    上传时间: 2022-05-06

    上传用户:

  • 基于Realtek RTL9047AA 的车用 7端口网路交换器方案

    RTL9047A 为车用乙太网single chip 交换机方案,如下图port0~port3 总共提供4ports 100BASE-T1,不用外挂PHY可节省cost 及PCB空间;port4为 selection port可选择设定100BASE-T1或SGMII,其SGMII个外接CPU或对接相同型号switch做cascade扩充;port5为 selection port可选择设定传统100base-TX FE PHY, SGMII或 RGMII/MII/RMII,其100base-TX 界面作为车载Diagnostic界面;port6为RGMII/MII/RMII 界面,可用来外接CPU或扩充网路界面等应用。

    标签: realtek rtl9047aa

    上传时间: 2022-06-07

    上传用户:

  • 基于滑模观测器与分数阶锁相环的无传感器PMSM矢量控制

    Abstract: A sliding mode observer and fractional-order phase-locked loop (FO-PLL) method is proposed for the sensorless speed control of a permanent magnet synchronous motor (PMSM).The saturation function is adopted in order to reduce the chattering phenomenon caused by the sliding mode observer. In this proposed FO-PLL, method, a regulable fractional order r is involved, which means that the FO-PLL provides an extra degree of freedom. In fact, the conventional phase-locked loop (PLL) applied in sensorless PMSM control can be seen as a special case of the proposed FO-PLL. By selecting a proper fractional order r a better performance may be achieved. The computer simulation results demonstrate the effectiveness of the proposed method.Key words: fractional calculus; fractional order phase-locked loop; sensorless control; sliding mode observer; permanent magnet synchronous motor; speed controll

    标签: 滑模观测器 传感器 pmsm 矢量控制

    上传时间: 2022-06-18

    上传用户:

  • MOSFET和IGBT区别

    MOSFET和IGBT内部结构不同, 决定了其应用领域的不同.1, 由于MOSFET的结构, 通常它可以做到电流很大, 可以到上KA,但是前提耐压能力没有IGBT强。2,IGBT 可以做很大功率, 电流和电压都可以, 就是一点频率不是太高, 目前IGBT硬开关速度可以到100KHZ,那已经是不错了. 不过相对于MOSFET的工作频率还是九牛一毛,MOSFET可以工作到几百KHZ,上MHZ,以至几十MHZ,射频领域的产品.3, 就其应用, 根据其特点:MOSFET应用于开关电源, 镇流器, 高频感应加热, 高频逆变焊机, 通信电源等等高频电源领域;IGBT 集中应用于焊机, 逆变器, 变频器,电镀电解电源, 超音频感应加热等领域开关电源 (Switch Mode Power Supply ;SMPS) 的性能在很大程度上依赖于功率半导体器件的选择,即开关管和整流器。虽然没有万全的方案来解决选择IGBT还是MOSFET的问题,但针对特定SMPS应用中的IGBT 和 MOSFET进行性能比较,确定关键参数的范围还是能起到一定的参考作用。本文将对一些参数进行探讨,如硬开关和软开关ZVS ( 零电压转换) 拓扑中的开关损耗,并对电路和器件特性相关的三个主要功率开关损耗—导通损耗、传导损耗和关断损耗进行描述。此外,还通过举例说明二极管的恢复特性是决定MOSFET或 IGBT 导通开关损耗的主要因素, 讨论二极管恢复性能对于硬开关拓扑的影响。导通损耗除了IGBT的电压下降时间较长外, IGBT和功率MOSFET的导通特性十分类似。由基本的IGBT等效电路(见图1)可看出,完全调节PNP BJT集电极基极区的少数载流子所需的时间导致了导通电压拖尾( voltage tail )出现。

    标签: mosfet igbt

    上传时间: 2022-06-21

    上传用户:

  • 基于LTspice的开关电源设计及仿真

    引言开关电源(SMPS:Switch Mode Power Supply)是利用现代电力电子技术,控制开关管开通和关断的时问比率,维持稳定输出电压的一种电源·非隔离式DC/DC变换具有六种基本拓扑结构:降压(Buck)变换器升压(Boost)变换器极性反转升降压(Buck2Boost)变换器Cuk(Boost2Buck 联)变换器Sepic变换器Zeta变换器[-1,与线性电源相比,开关电源具有体积小重量轻效率高自身抗干扰性强输出电压范围宽模块化等优点。LTspice IV是LT公司推出的SPICE电路仿真软件,具有集成电路图捕获和波形观测功能。LTspice IV内置新型SPIE元件,能快速进行SMPS交互式仿真,且无元件或节点数目的限制.LTspice IV虽然与开关模式电源设计配合使用,但它并不是SMPS专用型SPICE软件,而是一款通用型SPICE-LTspice IV内置了LT公司新型SPARSE矩阵求解器,采用专有的并行处理方法,实现了对任务的高效并行处理"。

    标签: ltspice 开关电源

    上传时间: 2022-06-26

    上传用户: