论文部分内容阅读
目前,国内生产的直流数字电压表,其最高灵敏度为0.1μV,距世界先进水平相差两个量级,为了把该项指标再提一个量级,我们研制了十毫微伏放大器。文中介绍了该放大器的原理,对MOS—FET斩波器进行了详细的分析。并从噪声理论出发,讨论了信号源阻抗,前级有源器件及工作点的选取;且引入“快速电路”较好地解决了通频带和灵敏度的矛盾,最后阐明了低噪电路的工艺要求。
At present, the domestic production of DC digital voltmeters, the highest sensitivity of 0.1μV, two levels away from the world’s advanced level, in order to mention the indicator an order of magnitude, we developed a ten nanofarad amplifier. This paper introduces the principle of the amplifier, MOS-FET chopper for a detailed analysis. Based on the theory of noise, this paper discusses the selection of signal source impedance, pre-active device and working point. The introduction of “fast circuit” solves the contradiction between passband and sensitivity, and finally illustrates the technical requirements of low-noise circuit .