基于MSP430的直流宽带放大器设计.pdf

2011 8 15 Aug. 2011 34 16 Modern Electronics T echnique Vol. 34 No. 16 基于MSP430 的直流宽带放大器设计 王晓斐, 封维忠, 吴海青 ( , 21003 ) : 以压控增益宽带放大器 VCA 810 为主, 配合低噪声高速运放 OPA820ID 和高输 电压低失真运放 TH S3091D, 设计并制作 一个基于超低功耗单片机MSP430F155 的 5 V 单电源供电的宽带低噪声放大器由单片机软件实现VCA 810 增益控制及输 波形幅值显示电压增益为- 20~ + 60 dB 可调, 在最大增益下, 通频带为10 H z~ 10 M Hz, 负载50 8 情况 下可输 峰峰值29 V 的电压为解决宽带放大器的自激问题及减小输 噪声, 采用了多种形式的抗干扰措施, 抑制噪声, 改善放大器的稳定性 : 宽带放大器; VCA 810; MSP430; 单电源; 峰值检测 :T N 22-34 : A : 1004-3 3X( 2011) 16-0116-03 Design of Broadband DC Amplifier Based on MSP43 0 WANG Xiao-fei, FENG We-i zhong, WU H a-i qing (Faculty of Inf ormat ion Science T echnology , Nanjing Forestry University, Nanjing 21003 , China) Abstract: A broadband and low noise amplifier supplied by 5V single power based on MSP430F155 is mainly const ituted by pressure control gain VCA810, OPA 820ID and TH S3091D. OPA 820ID has the feature of high-speed and TH S3091D can provide high output voltage and low distortion. The circuit is designed basing on t he ultralow powerful M SP430F 155. The gain control and parameter display are implemented by softw are. The voltage gain can be changed between - 20dB ~ + 60 dB. At the most gain, the bandwidth ranges from 10 Hz~ 10 MH z. In the event of loading 50 ohm, the output voltage peak is 29V . T o solve the problem of self-excit ed broadband am plifier output and reduce noise, the various forms of ant-i disturbance measures can be improved to im prove stability of the amplifier . Keyw ords: w ideband amplifier; VCA 810; MSP430; single pow er; peak detection , (4) , , 10