Instruments and Systems: Monitoring, Control, and Diagnostics Annotation << Back Design and Research of a Multidifferential Operational Amplifier of Secondary Sensor Converters for Monitoring and Control Systems S.V. FEDOROV This article discusses the problems of modern amplifiers used to convert the sensor signal. As a result of the conducted research, the circuit of an operational amplifi er based on the KR140UD1A was modeled in the Multisim environment. The parameters of this operational amplifi er were obtained, which are fully consistent with the reference data. The study of the parameters of this operational amplifier showed a low value of the common-mode input voltage attenuation coefficient, as well as a large value of the zero offset voltage. The solution to these problems is the use of a new class of active elements – multidifferential amplifiers. A multidiffential amplifier based on the operational amplifi er KR140UD1A was designed. Simulation modeling in the Multisim environment has shown the possibility of a significant improvement in its parameters. Thus, the use of multidifferential amplifiers provides precision amplifi cation of the differential signal and increased attenuation of the common-mode component of the input voltages. Keywords: multidiffential operational amplifier, instrumental amplifier, secondary converter, common-mode voltage attenuation coefficient, zero offset voltage. DOI: 10.25791/pribor.11.2021.1300 Pp. 01-08.