低压高频LC谐振电路设计.docx

LC谐振放大器设计与总结报告摘要本次电子线路设计对低压高频调谐小信号放大器，LC振荡器，高频功放电路设计原 理作了简要分析，研究了各个电路的参数设置方法并利用其它相关电路为辅助工具来调试 放大电路，解决了放大电路中经常出现的自激振荡问题和难以准确的调谐问题，同时还能满 足小功耗 同时也给出了具体的理论依据和调试方案，从而实现了快速、有效的分析和制 作高频放大器，振荡器和功放电路高频小信号谐振放大电路是将高频小信号或接收机中经变频后的中频信号进行放大， 已达到下级所需的激励电压幅度LC振荡器的作用是选出信号中需要的谐振频率高频功 放的作用是以高的效率输出最大的高频功率三部分都是通信系统中无线电收发信机所用到 的技术，所以在现实生活中具有着相当广泛的应用关键词：低压高频小信号放大器、LC振荡器、高频功放电路AGC反馈The electronic circuit design of low voltage high frequency tuned small-signal amplifier, LC oscillator, high frequency power amplifier circuit design principles provided a brief analysis study on parameter settings for each circuit. And other related circuits as a secondary tool to debug amplifier, solves amplifiers often self-excited oscillation problem and cannot be accurately tuning issues, while also meeting the small power consumption. At the same time also gives specific theoretical basis and debugging scenarios, which enables fast, efficient analysis and production of high-frequency amplifier, oscillator and amplifier circuit. High-frequency small-signal resonant amplifier is a high-frequency small-signal or to zoom the inverter if signal in the receiver, is required to achieve a lower excitation voltage range. LC oscillator elected is the role of resonance frequency of the signal needs. Effect of high frequency power amplifier is the largest with high efficiency output power. Three sections are radio transceiver used in communication systems technology, so in real life, with a fairly wide range of applications.Key words: low-voltage high-frequency small-signal amplifier, AGC LC oscillator, high frequency power amplifier circuit feedback1.系统方案设计及论证 本系统以参赛题目的要求为目的，采用分离式元件，高频小信号放大器一般用于放大微弱的高频信号，此类放大器应具备如下基本特性:只允许所需15MHZ的信号通过，具 有较高的选择性。

放大器的增益要足够大,需达 60dB 以上放大器工作状态应稳定且产生的 噪声要小放大器应具有一定的通频带宽度，本设计中要求达到300KHZ1.1 LC 谐振电路方案论证方案一：采用集成芯片 AD8307 和 AD8031 进行放大，工作电压为 2.7V〜5.5V,满足低电压要求经过理论计算两芯片的功耗和为86.5mW, 满足低功耗要求该方案采用单端输入，有对数零点和斜率调节电路， 将对数零点设在-84 dBm,斜率定为大约20 mV / dB对数放大器后加 一级缓冲（AD8031）,主要作用有二：一是使该模块最终输出是低阻抗的, 提高抗干扰能力；二是通过这一级的电压增益将对数斜率恢复到 25 mv / dB设计的对数放大器信号输入范围定为-72 dBm（在50 Q源阻抗时， -72 dBm相当于振幅为士80卩的正弦波）到+10 dBm（振幅为±1 V的正弦 波），相应的对数输出电压为0.3〜2.35 V,对数动态范围82 dBC4IO11F/I6V P1 C02, +3.6V 2VR2 50KU1AD8307■^rR3C03lOOOp :Hs inoSdA S84.7R236COcoVR16.34K / R4:C01 2KlOOOpDNCNC-hiVs++I11OuT-VsNCU2AD80318TR53K。