Fan Kuangang, Wu Baojun, Chen Renyi, Liu Pingchuan
School of Mechanical and Electrical Engineering, Jiangxi University of Science and Technology, Hongqi Street No. 86, Ganzhou, China.
Rev Sci Instrum. 2019 Feb;90(2):026106. doi: 10.1063/1.5078755.
In order to measure the low current in the quadrupole mass spectrometer (QMS), we design a novel wide band composite trans-impedance preamplifier. The noise filtering components, which built in the feedback loop of the preamplifier, are designed to reduce the noise of two-stage amplifiers. By using the package with low thermal resistance factor, reducing the power consumption of preamplifiers and reducing the feedback resistance, the temperature drift of baseline signal is reduced. Compared with the traditional composite preamplifier, the novel preamplifier reduces maximum temperature drift amplitude and reduces root mean square of noise. At last, the environmental reliability of QMS detection was improved.
为了测量四极杆质谱仪(QMS)中的微弱电流,我们设计了一种新型宽带复合跨阻前置放大器。内置在前置放大器反馈回路中的噪声滤波组件旨在降低两级放大器的噪声。通过使用具有低热阻系数的封装、降低前置放大器的功耗以及减小反馈电阻,基线信号的温度漂移得以降低。与传统复合前置放大器相比,新型前置放大器降低了最大温度漂移幅度,并降低了噪声的均方根。最后,提高了QMS检测的环境可靠性。