Adamiak O. Signal converters of organic semiconductor optocouplers for sensor electronics devices

The dissertation is devoted to the development and investigation of signal converters for sensor devices based on organic optocouplers. The work proposes new approaches to the modeling, analysis, optimization, and practical implementation of signal converters for sensor electronics, which are based on the use of organic semiconductors, as well as methods for monitoring the parameters of sensor devices. The first chapter presents a detailed overview of current trends in the development of sensor electronics, in particular the integration of organic components. The capabilities and advantages of organic electronics, especially optocouplers, in the creation of sensitive sensor elements are analyzed. Approaches to the development of SPICE models for electronic devices and their application in the design of sensor systems are described. The principles of operation of transimpedance amplifiers and their use in signal converters are considered, along with the fundamentals of impedance analysis for investigating the characteristics of sensor systems. The second chapter is dedicated to the development of SPICE macromodels for the components of the sensor optocoupler. Structural and functional models of the main modules–S_LED, S_HTQ, S_SEN, S_NOS, and S_PHD–have been developed. A parametric analysis of the components was performed to determine optimal characteristics and operational stability under external influences, including temperature and humidity. This enabled accurate and reliable modeling of the sensor system. The third chapter focuses on in-situ monitoring techniques for parameter drift in the sensor optocoupler. Methods for implementing quadrature signal detection are proposed, along with the development of a substitution model for an impedance type measurement converter and a specification of the impedance characteristics of photosensitive structures. A parametric analysis of signal converters with transimpedance amplifiers was carried out, allowing for optimized designs and improved measurement accuracy. The fourth chapter centers on the practical implementation of signal converters for sensor devices. A comprehensive analysis of signal conversion circuits based on organic optocouplers was conducted. A quadrature detector and signal converter based on a programmable PSoC system were implemented. Particular attention was given to the integration of signal converters into sensor systems and their adaptation for the detection of various physical quantities. The study combines theoretical research, modeling, and experimental testing of the developed prototypes, resulting in effective solutions for sensor electronics. The obtained results contribute to improved accuracy, stability, and reliability of sensors based on organic optocouplers and open up new possibilities for their application in various types of devices. The conclusions of the dissertation summarize the main findings and recommendations derived from the conducted research and present quantitative assessments of performance indicators under the proposed solutions. The appendices to the dissertation include documentation of the implementation of the dissertation results, as well as a list of the author's scientific publications and conference presentations related to the topic.