CIRCUIT DESIGN PROPOSALS FOR IMPROVING THE METROLOGICAL
CHARACTERISTICS OF A MICROMECHANICAL ACCELEROMETER WITH A CAPACITIVE DISPLACEMENT SENSOR 

Mikhail A. Vatutin, Candidate of technical sciences, associate professor, associate professor of the sub-department of autonomous control systems, Mozhaisky Military Space Academy (13 Zhdanovskaya street, Saint Petersburg, Russia),vatutinm@inbox.ru
Igor A. Shevkunov, Candidate of technical sciences, lecturer of the sub-department of autonomous control systems, Mozhaisky Military Space Academy (13 Zhdanovskaya street, Saint Petersburg, Russia), vka@mil.ru

Background. Modern accelerometers based on microelectromechanical systems (MEMS) have a very low cost, are distinguished by their miniaturization and low energy consumption. A high measurement error can be identified as one of the disadvantages of such sensors. One of the reasons for this is the significant sensitivity of radio components to changes in ambient temperature. The aim of the work is to improve the metrological characteristics of the accelerometer by increasing the stability of the converter part, made on a D-trigger. Materials and methods. The study showed that the accelerometer with a capacitive displacement sensor, built on a digital D-trigger microcircuit, do not have high accuracy parameters, and it is also difficult to determine them. The proposed buffer comparator makes it possible to eliminate these disadvantages. The accuracy parameters of the buffer comparator elements are estimated. A mathematical model of the accelerometer has been developed to assess the stability of the parameters of the time interval shaper. The stability of the conversion in the time interval for various typical elements of the buffer comparator is estimated. The influence of auxiliary parameters of radio elements on the stability of the buffer comparator has been evaluated. Circuit design solutions are proposed to improve the stability of an accelerometer with a capacitive displacement sensor. Results. The presented circuit design proposals make it possible to increase the stability of the conversion by an accelerometer with a capacitive displacement sensor. The presented results can also be used for a wide range of measuring instruments in which capacitive type motion sensors are used to measure a physical quantity. Conclusions. The application of the studied circuit design proposals makes it possible to increase the stability of the threshold levels of the converter D-trigger and, thereby, to achieve a more accurate conversion of the input signal. The results can be used in the construction of a wide range of measuring instruments of physical quantities for use in industrial devices and in other fields of science and technology.

accelerometer, capacitive primary information sensor, digital circuit generator, conversion stability, radio element parameter drift, reference voltage source

Vatutin M.A., Shevkunov I.A. Circuit design proposals for improving the metrological characteristics of a micromechanical accelerometer with a capacitive displacement sensor. Izmerenie. Monitoring. Upravlenie. Kontrol' = Measuring. Monitoring. Management. Control. 2025;(2):80–90. (In Russ.). doi: 10.21685/2307-5538-2025-2-10