射频宽带高增益放大电路的设计  

Design of the RF Wideband and High-gain Amplifier Circuit

作　　者：杨成林 Yang Chenglin(Xinzhou Medium Wave Broadcasting Station,Shanxi Province Press and Publication Radio and Television Bureau,Taiyuan Xinzhou 034000,China)

机构地区：[1]山西省广播电视局忻州中波转播台,山西忻州034000

出　　处：《山西电子技术》2018年第6期67-70,共4页Shanxi Electronic Technology

摘　　要：本设计由宽带放大器OPA847、压控放大器VCA824和电流型运放OPA695构成射频宽带放大电路。放大电路前级由OPA847实现20 d B放大,中间级由压控放大器VCA824实现0. 05 V/V～5 V/V的增益变化,后级由OPA695和继电器实现5 V/V～25 V/V的增益变化,末级由电阻网络进行20 dB衰减,达到在0dB～60dB增益范围内可调。The system is designed with a broadband amplifier OPA847,voltage controlled amplifier VCA824 and current-feedback operational amplifier OPA695.In the first stage,the system can achieve 20 dB fixed-gain by OPA847.Then,in the intermediate stage,it uses VCA824 to achieve 0.05~5V/V gain range.In the latter part,the system achieves 5~25V/V gain variation by OPA695 and relays.In the last stage,the system achieves 20dB attenuation by the resistor network,so that the overall gain can be adjusted in the range of 0~60dB.

关 键 词：射频放大器 VCA824 OPA847 OPA695 

分 类 号：TN934.81[电子电信—信号与信息处理]