本文介绍了AD公司的RF/IF相位和幅度测量芯片AD8302,并以此芯片为核心,组合功分器、延迟线和FPGA芯片设计了瞬时测频接收机,改进了传统的设计方案。依照设计制作了测频系统,并对系统整体性能进行了测试,测试结果表明本系统可以准确测量1.4~2.0 GHz范围内的信号,测频精度为10 MHz。
上传时间: 2013-10-26
上传用户:zsjzc
本书内容包括三大部分:第1 部分从运算放大器的基本概念和理论出发,重点介绍了运算放大器的原理与设计,以及在各种电子系统中的应用,包括视频应用、RF/IF 子系统(乘法器、调制器和混频器)等;第2 部分主要介绍了高速采样和高速ADC 及其应用、高速DAC 及其应用、以及DDS 系统与接收机子系统等;第3 部分介绍了有关高速硬件设计技术,如仿真、建模、原型、布局、去藕与接地,以及EMI 与RFI设计考虑等。 书中内容既有完整的理论分析,又有具体的实际应用电路,还包括许多应用技巧。特别适合电子电路与系统设计工程师、高等院校相关专业师生阅读。
上传时间: 2013-11-16
上传用户:qitiand
Abstract: IF sensitive analog systems are run from one supply without the sufficient bypassing to eliminate noise,
上传时间: 2013-11-23
上传用户:qiulin1010
Precision 16-bit analog outputs with softwareconfigurableoutput ranges are often needed in industrialprocess control equipment, analytical and scientIFicinstruments and automatic test equipment. In the past,designing a universal output module was a daunting taskand the cost and PCB real estate associated with thisfunction were problematic, IF not prohibitive.
上传时间: 2014-12-23
上传用户:如果你也听说
Designers of signal receiver systems often need to performcascaded chain analysis of system performancefrom the antenna all the way to the ADC. Noise is a criticalparameter in the chain analysis because it limits theoverall sensitivity of the receiver. An application’s noiserequirement has a signIFi cant infl uence on the systemtopology, since the choice of topology strives to optimizethe overall signal-to-noise ratio, dynamic range andseveral other parameters. One problem in noise calculationsis translating between the various units used by thecomponents in the chain: namely the RF, IF/baseband,and digital (ADC) sections of the circuit.
上传时间: 2014-12-05
上传用户:cylnpy
This application note is an overview discussion of theLinear Technology SPICE macromodel library. It assumeslittle IF any prior knowledge of this software library or itshistory. However, it does assume familiarity with both theanalog simulation program SPICE (or one of its manyderivatives), and modern day op amps, including bipolar,JFET, and MOSFET amplIFier technologies
上传时间: 2013-11-14
上传用户:zhanditian
Sensors for pressure, load, temperature, acceleration andmany other physical quantities often take the form of aWheatstone bridge. These sensors can be extremely linearand stable over time and temperature. However, mostthings in nature are only linear IF you don’t bend them toomuch. In the case of a load cell, Hooke’s law states that thestrain in a material is proportional to the applied stress—as long as the stress is nowhere near the material’s yieldpoint (the “point of no return” where the material ispermanently deformed).
上传时间: 2013-11-13
上传用户:墙角有棵树
Finite state machines are widely used in digital circuit designs. Generally, when designing a state machine using an HDL, the synthesis tools will optimize away all states that cannot be reached and generate a highly optimized circuit. Sometimes, however, the optimization is not acceptable. For example, IF the circuit powers up in an invalid state, or the circuit is in an extreme working environment and a glitch sends it into an undesired state, the circuit may never get back to its normal operating condition.
标签: Creating Machines Mentor State
上传时间: 2013-10-08
上传用户:wangzhen1990
DAC34H84 是一款由德州仪器(TI)推出的四通道、16 比特、采样1.25GSPS、功耗1.4W 高性能的数模转换器。支持625MSPS 的数据率,可用于宽带与多通道系统的基站收发信机。由于无线通信技术的高速发展与各设备商基站射频拉远单元(RRU/RRH)多种制式平台化的要求,目前收发信机单板支持的发射信号频谱越来越宽,而中频频率一般没有相应提高,所以中频发射DAC 发出中频(IF)信号的二次谐波(HD2)或中频与采样频率Fs 混叠产生的信号(Fs-2*IF)离主信号也越来越近,因此这些非线性杂散越来越难被外部模拟滤波器滤除。这些子进行pcb设计布局,能取得较好的信号完整性效果,可以在pcb打样后,更放心。这些杂散信号会降低发射机的SFDR 性能,优化DAC 输出的二次谐波性能也就变得越来越重要。
上传时间: 2013-10-23
上传用户:lalalal
Boost LED drivers are often used to drive LEDs in series. IF an LED fails while open,overvoltage protection (OVP) is necessary to avoid the damage to a boost integrated circuit (IC) or output capacitor. This application report presents the solutions to increase the TPS61043 LED driver OVP threshold.
标签: Overvoltage Protection Solutions Driver
上传时间: 2013-10-14
上传用户:jiangfire