本文介紹了AD公司的RF/if相位和幅度測量芯片AD8302，并以此芯片為核心，組合功分器、延遲線和FPGA芯片設計了瞬時測頻接收機，改進了傳統的設計方案。依照設計制作了測頻系統，并對系統整體性能進行了測試，測試結果表明本系統可以準確測量1.4~2.0 GHz范圍內的信號，測頻精度為10 MHz。
上傳時間： 2013-10-26
上傳用戶：zsjzc
本書內容包括三大部分：第1 部分從運算放大器的基本概念和理論出發，重點介紹了運算放大器的原理與設計，以及在各種電子系統中的應用，包括視頻應用、RF/if 子系統(乘法器、調制器和混頻器)等;第2 部分主要介紹了高速采樣和高速ADC 及其應用、高速DAC 及其應用、以及DDS 系統與接收機子系統等;第3 部分介紹了有關高速硬件設計技術，如仿真、建模、原型、布局、去藕與接地，以及EMI 與RFI設計考慮等。 書中內容既有完整的理論分析，又有具體的實際應用電路，還包括許多應用技巧。特別適合電子電路與系統設計工程師、高等院校相關專業師生閱讀。
上傳時間： 2013-11-16
上傳用戶：qitiand
Abstract: if sensitive analog systems are run from one supply without the sufficient bypassing to eliminate noise,
上傳時間： 2013-11-23
上傳用戶：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.
上傳時間： 2014-12-23
上傳用戶：如果你也聽說
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.
上傳時間： 2014-12-05
上傳用戶：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
上傳時間： 2013-11-14
上傳用戶：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).
上傳時間： 2013-11-13
上傳用戶：墻角有棵樹
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.
標簽： Creating Machines Mentor State
上傳時間： 2013-10-08
上傳用戶：wangzhen1990
DAC34H84 是一款由德州儀器（TI）推出的四通道、16 比特、采樣1.25GSPS、功耗1.4W 高性能的數模轉換器。支持625MSPS 的數據率，可用于寬帶與多通道系統的基站收發信機。由于無線通信技術的高速發展與各設備商基站射頻拉遠單元（RRU/RRH）多種制式平臺化的要求，目前收發信機單板支持的發射信號頻譜越來越寬，而中頻頻率一般沒有相應提高，所以中頻發射DAC 發出中頻（if）信號的二次諧波（HD2）或中頻與采樣頻率Fs 混疊產生的信號（Fs-2*if）離主信號也越來越近，因此這些非線性雜散越來越難被外部模擬濾波器濾除。這些子進行pcb設計布局，能取得較好的信號完整性效果，可以在pcb打樣后，更放心。這些雜散信號會降低發射機的SFDR 性能，優化DAC 輸出的二次諧波性能也就變得越來越重要。
上傳時間： 2013-10-23
上傳用戶：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.
標簽： Overvoltage Protection Solutions Driver
上傳時間： 2013-10-14
上傳用戶：jiangfire
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