共查询到18条相似文献,搜索用时 843 毫秒
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低谐波失真的CMOS正弦波振荡器设计 总被引:1,自引:0,他引:1
本文设计了一种具有低谐波失真输出的CMOS正弦波振荡器.该振荡器以RC有源微分电路作为选频回路.在实际电路设计中应计及运算放大器的频率特性,由此可得RC有源微分电路为二阶高Q电路.该电路具有良好的选频特性,大幅降低了振荡器输出的谐波失真,并配合移相和可变增益电路以满足振荡器起振条件.使用本文设计的CMOS运算放大器,该振荡器可起振的带宽可达200 Hz~2 MHz,其谐波失真小于通带噪声.以输出正弦波频率为100 kHz为例,给出了Hspice仿真结果. 相似文献
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本文设计并实现了一种微波锁相环中取样器的本振电路,取样本振以频率合成芯片ADF4002为鉴相器,反馈通道采用内插混频器的结构,避免了单环通过简单倍频产生的相位噪声恶化。详细阐述了取样本振电路的实现方案和工作原理,并使用仿真软件对环路滤波器进行设计。通过实验测试,输出频率为214.815MHz时锁相环的相位噪声为:-137dBc/Hz@10kHz、-140dBc/Hz@100kHz,最大输出频率间隔1MHz,满足了取样本振的低相位噪声和高频率分辨率的要求。 相似文献
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一个基于CCⅡ+的RC正弦振荡器 总被引:3,自引:0,他引:3
本提出了由一个同相第二代电流传输器(CCⅡ+)、两个电容和两个电阻构成的RC正弦振荡器电路。该电路能输出幅度大、频率和幅值可以调节的正弦信号。章分析了起振条件,给出了振荡频率公式和电路的实验结果。 相似文献
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该防盗报警器电路不复杂,可三路同时报警。单路耗电小于8mA。文章介绍了电路原理、印刷板图、安装方法。中任一个开关断开,就使非门某端成低电平,输出成高电平,通过二极管加到振荡器的控制端,振荡器起振,通过C:右面元件组成 相似文献
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针对行间转移型面阵电耦合器件(CCD)ICX415AL,分析其驱动时序要求和工作原理,以现场可编程门阵列(FPGA)芯片EP4CE10F17C8为主控芯片,QuartusⅡ软件为开发平台,选择Verilog HDL语言设计各驱动时序信号。结合反相器和驱动芯片构建CCD外围驱动电路,利用Modelsim SE仿真软件进行联合仿真测试,得到了正确的时序波形输出,将FPGA产生的驱动时序信号接入CCD驱动电路,通过示波器观察CCD在不同条件下输出相对应的视频信号。实验结果表明,所设计的驱动电路运行稳定,满足ICX415AL各项驱动要求。 相似文献
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设计了一种用于升压式DC-DC开关电源的新型软启动电路。该电路结构简单、稳定性强、易于集成、功耗较低,不仅能有效地抑制DC-DC开关电源在启动时产生的浪涌电流,而且能避免电压过冲现象,保证输出电流上升的稳定性和可靠性。该电路采用0.5μm CMOS工艺进行设计,已成功集成到一款升压式DC-DC开关电源芯片内。测试结果表明,在输入电压为3.6 V,输出电流为100 mA的工作状态下,输出电流分四段台阶平稳上升、无电压过冲现象,启动时间控制在140μs以内。 相似文献
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Jens Masuch Manuel Delgado‐Restituto 《International Journal of Circuit Theory and Applications》2013,41(1):33-43
This paper presents different alternatives for the implementation of low‐power monolithic oscillators for wireless body area networks and describes the design of two quadrature generators operating in the 2.4‐GHz frequency range. Both implementations have been designed in a 90‐nm Complementary Metal‐Oxide Semiconductor (CMOS) technology and operate at 1 V of supply voltage. The first architecture uses a voltage‐controlled oscillator (VCO) running at twice the desired output frequency followed by a divider‐by‐2 circuit. It experimentally consumes 335 μW and achieves a phase noise of ?110.2 dBc/Hz at 1 MHz. The second architecture is a quadrature VCO that uses reinforced concrete phase shifters in the coupling path for phase noise improvement. Its power consumption is only 210 μW, and it obtains a phase noise of ?111.9 dBc/Hz at 1 MHz. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Jong‐Wan Kim Hidekuni Takao Kazuaki Sawada Makoto Ishida 《IEEJ Transactions on Electrical and Electronic Engineering》2007,2(3):365-371
This paper presents the essentials of the development of an integrated smart microsensor system that has been developed to monitor the motion and vital signs of humans in various environments. Integration of RF transmitter technology with complementary metal‐oxide‐semiconductor/micro electro mechanical systems (CMOS/MEMS) microsensors is required to realize wireless smart microsensors for the monitoring system. Sensors for the measurement of body temperature, perspiration, heart rate (pressure sensor), and motion (accelerometers) are candidates for integration on the wireless smart microsensor system. In this paper, the development of radio frequency transmitter (RF) that will be integrated on wireless smart microsensors is presented. A voltage controlled RF‐CMOS oscillator (VCO) has been fabricated for the 300‐MHz frequency band applications. Also, spiral inductors for an LC resonator and an integrated antenna have been realized with a CMOS‐compatible metallization process. The essential RF components have been fabricated and evaluated experimentally. The fabricated CMOS VCO showed a conversion factor from voltage to frequency of about 81 MHz/V. After matching the characteristic impedance (50 Ω) of the on‐chip integrated antenna and the VCO output, more than 5 m signal transmission from the microchip antenna has been observed. The transmitter showed remarkable improvement in transmission power efficiency by correct matching with the microchip antenna. Essential technologies of the RF transmitter for the wireless smart microsensors have been successfully developed. Also, for the 300‐MHz band application, the integrated RF transmitter, with the CMOS oscillator and the on‐chip antenna, has been successfully demonstrated for the first time. Copyright © 2007 Institute of Electrical Engineers of Japan© 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
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提出了一种基于电力线载波通信(power line commun- ication,PLC)技术的逆变器并联系统输出同步控制方法,应用于实现硬件无互连线方式的逆变电源并联系统。各并联模块之间通过PLC方式交换各自电压基准正弦信号的频率和相位信息,调节并保持输出电压同频、同相,在此基础上再实现逆变器模块输出均流。研究了同步控制原理,提出了同步调节控制算法,设计了基于数字信号处理器(digital signal processor,DSP)的软硬件实现。理论分析和实验结果证实了控制策略的有效性和可行性。 相似文献
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双向放大器是远距离通信应用中专为扩展无线设备的工作范围而设计,根据不同系统需要,对双向放大器输出功率的要求也有所不同。该设计中双向放大器的输出要求为0.5W,为达到该指标,选用PIC16f88芯片构成双向放大器的自动增益控制电路,并运用MPLABIDE软件编写自动输入电平检测及增益输出控制程序;同时根据衰减器的具体工作情况,采用IM4A5芯片构成数字显示电路,运用Quartus软件编写衰减值显示程序,通过该程序控制,可对输出的衰减控制信号的变化情况进行显示。实验表明,该设计能在一定范围内利用衰减器满足双向放大器的0.5w的输出功率要求,并对衰减器的衰减值进行显示,在实际应用中有较好的效果。 相似文献