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Novel on-chip circuit for jitter testing in high-speed PLLs 总被引:1,自引:0,他引:1
Cazeaux J.M. Omana M. Metra C. 《IEEE transactions on instrumentation and measurement》2005,54(5):1779-1788
We propose a novel on-chip circuit to measure the jitter present at the output of phase-locked loops (PLLs) used for generating phase-synchronous, frequency-multiplied clocks. This measure is performed at every period of the PLL reference clock, and a digital output encoded by means of a thermometer code is obtained. Such a digital output is then analyzed in order to confirm on-chip whether or not the jitter is within specifications. Our proposed circuit is able to test PLLs providing an output frequency in the gigahertz range. Compared to alternate techniques, that proposed here requires lower costs in terms of area overhead (requiring an area <12% of the PLLs' area) and circuit complexity, while featuring higher or comparable accuracy and lower or comparable test time. 相似文献
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An analytical assessment for multiport structures as direct conversion receivers is presented. A new direct-conversion receiver based on a novel five-port structure suitable for software-defined radio applications is proposed. The five-port architecture provides some advantages compared with previous architectures. Numerical and microwave simulations have been conducted to show its capabilities as a direct demodulator. The proposed five-port has been constructed and the measured results indicate that the five-port receiver introduced can be used effectively as a software-defined radio receiver 相似文献
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The authors introduce a new class of the microwave and millimeter wave multiport receivers. These receivers are designed based on a new five-port structure and offer a wide bandwidth. The low-cost implementation is the other advantage of this structure. The numerical and microwave simulations have been conducted to investigate the characteristics of the receiver. In addition, the new five-port receiver has been constructed and measured. The analytical and measurement results are in good agreement with each other. This indicates that the structure can effectively be used as a high-performance and low-cost wideband receiver for broadband applications. As a practical application, the European and North-American local multipoint distribution services band can be covered using this new architecture. 相似文献
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This paper presents a built-in self-test (BIST) circuit that measures the clock jitter of the charge-pump phase-locked loops (PLLs). The jitter-measurement structure is based on a novel time-to-digital converter (TDC) which has a high resolution. A small area overhead is also achieved using the voltage-controlled oscillator and the loop filter of the PLL under test as parts of the TDC. The experiment result shows that the resolution is about 1 ps and that the measurement error is smaller than 20%. 相似文献
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针对传统建筑能耗监测系统存在采集单元功耗高和布线复杂的问题,设计了一种低功耗的无线监测系统。所设计的监测系统包括采集单元、集中器、监测中心和通信网络四部分。其中:采集单元主要由计量电路和BLE(Bluetooth low energy,低功耗蓝牙)通信电路组成,其通过计量电路采集用电设备的能耗数据,并通过BLE通信电路将处理好的能耗数据发送至集中器;集中器主要由BLE通信电路和Wi-Fi通信电路组成,其通过BLE通信电路接收采集单元计量的能耗数据并进行整合、处理,然后通过Wi-Fi通信电路将能耗数据转发至监测中心;监测中心采用B/S(browser/server,浏览器/服务器)架构进行设计,其通过监测界面显示能耗数据并将数据保存在数据库中。所设计的监测系统通过采用BLE和Wi-Fi的通信方式降低了采集单元的运行功耗和布线复杂度,并延长了通信距离;基于B/S架构设计的监测中心可实现跨平台运行,提高了系统的灵活性。测试结果表明,所设计的监测系统的计量偏差率低于5%,通信成功率高于98%,且能够及时监测用电设备的耗能状况,具有较高的实用价值。 相似文献
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超声检测系统中数据采集电路的柔性设计 总被引:2,自引:0,他引:2
介绍了一种数据采集硬件电路的柔性设计方法,在为柔性数据采集板卡配置的CPLD柔性资源和柔性接口资源基础上,使板卡上的基本功能与二次设计的柔性功能相结合,实现了系统中的检测周期、特征信号变换控制与数据采集之间的硬件同步与控制。在电路设计中没有传统的PCB制作和电子元器件的焊接工序,整个专用数据采集电路系统设计可在不到一天时间内完成。 相似文献
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介绍了高速采集电路的一个现场数据采集系统的前端.该采集电路由高速A/D,CPLD及高速存储器构成,类似数字示波器或采样卡,具有高速采样,高速缓存以及完整的触发设置功能,适合采集高速瞬时信号.但与通用信号采集产品不同的是该产品具有开放的总线接口.可直接连接各种单片微机,DPS或微处理器,适用于嵌入式系统的应用场合.描述了该电路的功能和原理,重点讨论“Roll Mode”逻辑及其如何实现对高速瞬时信号的捕获功能. 相似文献
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为满足有关岩石破裂电磁辐射研究的需要,研制一套电磁辐射监测系统。该系统由电磁感应探头、信号调理电路和数据采集系统组成,可对频率在1kHz~1MHz内的微弱电磁场进行监测。电磁感应探头可感应空间中某一方向的电磁场变化,并将其转换成电信号;信号调理电路对探头输出的电信号进行放大、滤波,并实现放大滤波电路与计算机的电气隔离;数据采集软件基于LabVIEW编写,用于对监测到的信号进行记录和显示。实验结果表明:该系统性能稳定,操作简便,能够有效地监测岩石破裂所产生的电磁辐射,对岩石、混凝土等材料的力-电-磁研究具有重要意义。 相似文献
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针对GPS接收机抗干扰能力强的特点.分析了窄带干扰对接收机的捕获性能的影响.在扩频理论的基础上.给出了GPSC/A码接收机信号捕获的数学模型,计算得出平均捕获时间与捕获时间方差,给出窄带干扰下的接收机信号捕获的仿真结果.结果表明.当窄带干扰功率超过一定的值时,会导致GPS接收机捕获性能的严重恶化. 相似文献
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A sufficient set of criteria is presented for the verification of frequency synthesizers. Failure modes are identified for automatic gain control (AGC), phase-locked loop (PLL), and voltage-controlled oscillator (VCO) circuits. Low- and high-frequency noise, thermal, and vibration effects are presented for VCOs and PLLs. 相似文献
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设计一种基于斜波式发生器原理可编程数字控制精密延时电路,用恒流源电路充放电和18位的DA转换器分别接入高速比较器的两端,DA转换器预先设定一电压基准,恒流源充电电容达到电压基准,高速比较器开始反转,形成一个触发脉冲信号,然后充电电容通过高速二极管快速放电重新计时。设计成18bit数字控制可编程动态范围2ps的采集时间间隔,提高采集信号的精度和频率。 相似文献
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便携式测量系统中彩色线阵CCD数据采集电路的设计 总被引:1,自引:0,他引:1
本文提出了将彩色线阵CCD光电传感器用于现代便携式测量系统的设计方案.针对便携式系统尺寸小、功耗低的特点,设计了彩色线阵CCD的数据采集电路.该电路的功能是获取便携式毒气测量仪中侦毒管内的化学试剂发生化学反应前后的颜色信息,从而最终使整个测量系统完成毒气种类和毒气浓度的判别.该电路包含CCD器件的驱动电路,模拟信号的数字化电路和数据存储电路,以及电源控制电路等模块.该数据采集电路具有高速,节能的特点.使用该电路对被测物模型进行实际测量,显示了该数据采集电路的有效性.该数据采集电路测量侦毒管颜色变化长度的分辨力为0.06 mm. 相似文献
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故障特征信息的获取和处理对电路故障的可靠分类和准确诊断有很大的影响.在电路故障诊断时,对于不同的故障模式,存在信息混叠的现象,需要解决特征信息的有效提取和故障的可靠分类等问题.为此,本文提出了一种结合灵敏度特性分析的BP神经网络故障诊断方法.基本思想是通过灵敏度的计算,对电路故障样本作预分类,再根据电路灵敏度的计算结果分别提取相应特征信息,以此构造故障样本特征集,然后作为BP神经网络的输入对网络训练,并进行故障诊断.对滤波器的仿真结果表明,该方法能分类不同的元件故障,且对模拟电路故障诊断的平均正确率优于传统方法. 相似文献
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针对目前同步电机参数辨识方法存在的对输入扰动信号要求严、不能计及非线性因素等缺陷,对同步电机参数在线小扰动辨识技术进行了研究.构建了同步电机参数在线采集系统,建立了同步电机的恰当电路模型和状态方程,采用最大似然估计法在轻载和低励磁状态下辨识电机的线性参数,然后在磁路饱和状态下对饱和参数进行辨识修正,最后在大扰动的情况下,对参数和模型进行检验、修正.仿真计算结果与实测数据吻合较好,证明了文中所提出的同步电机参数辨识技术的有效性. 相似文献