Evaluation of Characteristics of HV Electrometric Amplifier with
In certain special applications,for example in various fields of chemistry,it is necessary to measure voltage in the order of hundreds of volts from a high-impedance source.Standard electrometric operational amplifiers cannot be used as their input range is limited to the maximum of ten volts.Furthermore,it is impossible to increase the input range by a voltage divider in situations when the required input resistance is,for example,1014Ω.A common resistive divider in the input of an operational amplifier typically shows the maximum input resistance of 1012Ω.A special circuit arrangement can be used in which the amplifier supply voltage is dynamically shifted with the input voltage.This configuration saves the high input resistance of the applied electrometric amplifier and extends the input voltage range to the desired value.In our configuration,the extended range is §300 V.The proposed design of an HV electrometric amplifier utilizes a high-voltage differential amplifier,which regulates the high-voltage source supplying the electrometric operational amplifier.The general feedback loop has to be frequency-compensated,and this compensation is designed using the Pspice simulator.Characteristics of the HV electrometric amplifier were confirmed by the measurement of freezing potentials.
Z.Roubal R.Kadlec
Department of Theoretical and Experimental Electrical Engineering,Brno University of Technology Kolejní 2906/4,Brno 61200,Czech Republic
国际会议
Progress in Electromagnetics Research Symposium 2011(2011年电磁学研究新进展学术研讨会)
苏州
英文
995-999
2011-09-01（万方平台首次上网日期，不代表论文的发表时间）