Abstract:

The article presents the use of the NI Multisim software platform for teaching and researching of parameters of integrated amplifiers in university courses in electronic circuitry.

The establishment of models for simulation study of parameters of integrated amplifiers using analysis environments directly corresponds to the introduction of new learning technologies that provide knowledge without the limitations that traditional way of teaching has. The main advantages of the application of Operational Amplifiers (Op Amps) in electronic circuitry are that the addition of a small number of external elements, which allows the creation of various circuits of functional devices for signal processing. The great variety of Op Amps, the possibility for realization of analogue and digital circuits together with the small sizes and the low price of a significant part of them have all contributed to turning them into a universal building component. This requires students to develop skills for determining the parameters of the Op-Amps, which are relevant to the applications that are considered to be appropriate.

Computer models for researching the parameters of operational amplifiers are developed on the basis of the studied teaching material and follow the trends for the development of electronic circuitry. They assist students in studying and measuring the input and output resistance of Op Amps, in determining the influence of DC parameters of the inverting Op-Amps and provide opportunities for independent work in order to acquire lasting knowledge in this area. The developed models and the research conducted with them, presented in the article, have been tested in the online training of students during the COVID-19 lockdown in the discipline "Electronic Circuitry" in the specialties "Computer and Communication Systems" and "Hardware and Software Systems" at the Faculty of Physics and Technology of Plovdiv University "Paisii Hilendarski".

The results of simulation studies for determining the input and output resistance of an inverting integrated amplifier implemented with IC TL082CD are presented and a comparative analysis with the theoretically calculated values is made as well.

The article contains some simulation studies that have been carried out and presents the results for determining the influence of the polarizing currents and the asymmetry voltage on the operation of an inverting integrated amplifier implemented with IC LM 741EH. The obtained results are compared to the theoretically calculated ones. The amplitude-frequency and phase-frequency characteristics of the same integrated amplifier are simulated and presented too.
Operational amplifiers are present in the construction of key units in electronics, automation and communications. When it comes to the process of designing and verifying devices implemented with Op-Amps, many simulation procedures and physical experiments are combined. The purpose of training in this area is to create sustainable knowledge and skills that lead to the acquisition and design of advanced and new schemes and devices.

The shared experiences of the authors in this article support the application of the Industry 4.0 paradigm and the challenges facing Science, Technology, Engineering, Math (STEM) Education. The authors focus their efforts on improving the opportunities for better corresponding between the required skills and the subjects taught.

Keywords:

Parameters of integrated amplifiers, simulation study, COVID-19 lockdown.