pg.PAGE\*MERGEFORMAT22增益带宽可调放大器摘要：本系统是由前级稳定放大电路，程控增益放大电路，程控的低通滤波器，功率放大电路，峰峰值显示和检测模块组成。前级稳定放大电路，由低噪声，单位增益稳定的OPA637实现。程控增益放大电路则是用VCA810，通过提供偏置电压来改变放大的倍数。程控低通滤波则是以控制Max5160来改变电阻值实现对两阶的巴特沃斯低通滤波器截止频率的调整，。功率放大电路则是用THs3091。峰峰值显示和检测，通过有效值采集芯片AD637，使系统输入为正弦波时，输出电压的峰峰值和有效值的数字显示功能。关键字：可变增益放大器，程控滤波器，THS3091，AD637目录TOC\o"1-3"\h\z\uHYPERLINK\l"_Toc426410330"一、系统方案设计PAGEREF_Toc426410330\h3HYPERLINK\l"_Toc426410331"1.系统总体构成（设计框图）PAGEREF_Toc426410331\h3HYPERLINK\l"_Toc426410332"2.方案比较PAGEREF_Toc426410332\h3HYPERLINK\l"_Toc426410333"（1）缓冲放大部分PAGEREF_Toc426410333\h3HYPERLINK\l"_Toc426410334"（2）压控增益电路PAGEREF_Toc426410334\h4HYPERLINK\l"_Toc426410335"（3）程控滤波电路PAGEREF_Toc426410335\h4HYPERLINK\l"_Toc426410336"（4）功率放大模块PAGEREF_Toc426410336\h4HYPERLINK\l"_Toc426410337"（5）有效值采集模块PAGEREF_Toc426410337\h5HYPERLINK\l"_Toc426410338"二.数据分析PAGEREF_Toc426410338\h5HYPERLINK\l"_Toc426410339"1.增益带宽积PAGEREF_Toc426410339\h5HYPERLINK\l"_Toc426410340"2.增益分配分析PAGEREF_Toc426410340\h5HYPERLINK\l"_Toc426410341"3.通频带内增益起伏控制PAGEREF_Toc426410341\h5HYPERLINK\l"_Toc426410342"4.抑制零点漂移PAGEREF_Toc426410342\h6HYPERLINK\l"_Toc426410343"5.放大电路稳定PAGEREF_Toc426410343\h6HYPERLINK\l"_Toc426410344"三.电路设计PAGEREF_Toc426410344\h6HYPERLINK\l"_Toc426410345"1.缓冲放大部分PAGEREF_Toc426410345\h6HYPERLINK\l"_Toc426410346"2.可控增益程控放大PAGEREF_Toc426410346\h7HYPERLINK\l"_Toc426410347"3.程控滤波电路PAGEREF_Toc426410347\h7HYPERLINK\l"_Toc426410348"4.功率放大模块PAGEREF_Toc426410348\h8HYPERLINK\l"_Toc426410349"5.有效值检测电路PAGEREF_Toc426410349\h9HYPERLINK\l"_Toc426410350"三.测试方法与数据PAGEREF_Toc426410350\h10HYPERLINK\l"_Toc426410351"1.测试仪器PAGEREF_Toc426410351\h10HYPERLINK\l"_Toc426410352"2.测量方案与数据PAGEREF_Toc426410352\h10HYPERLINK\l"_Toc426410353"(一)可控电压增益≥40dB测量及峰峰值的检测PAGEREF_Toc426410353\h10HYPERLINK\l"_Toc426410354"（二）滤波器上限截止频率的检测PAGEREF_Toc426410354\