Abstract:

Some of the goals in engineering education courses rely on the balance on theory and practice and fostering practical and critical thinking skills on a “learning by doing” basis. One of the subjects in electronics courses that students tend to find more difficult is the operation of differential amplifier stages. Among others, some of the difficulties mentioned are related to the way the amplifier stage is biased, i.e., using current sources instead of more traditional voltage bias sources; the common and differential modes of operation, and also the large and the small signal analysis. In fact these subjects required from students a higher level of abstraction in order to better understand it. On one hand it is required that students have a good knowledge on the MOSFET and BJT transistors characteristics and operating modes, and also the dynamic parameters and models of these devices. On the other hand, it is also required that they have a good knowledge of electronics and circuit analysis laws and theorems. The task of learning this subject can become facilitated from a practical application perspective, by using an integrated approach that includes circuit simulation and a versatile lab KIT based on discrete components and devices.

This paper presents and discuss the authors’ experience on developing the differential amplifier kit and its adoption to teaching telecommunication electronics subjects, with a strong focus on practical applications and laboratory equipment usage, to strength their technical skills. The kit is reconfigurable and suited for either MOSFET or BJT differential amplifiers. The lab experiments proposed also enable the study of current source biasing, as alternative to more traditional methods based on voltage sources. The test protocols for each experiment rely on mandatory simulation results, a priori, in order to support the experimental results with emphasis on the datasheets parameters and their influence and interconnection on the amplifier operation and performance.

The courses taught comprise analog electronics and telecommunications electronics, such as analog modulation fundamentals, within a bachelor degree in Electronics and Telecommunications. The methodology the approach, the resources used and some experiments are presented and discussed. The students’ workload and effort are measured, the academic success rate is evaluated and the skills acquirement are pointed out based on the results achieved, taking into account the complexity of the proposed problems, the correctness of the solutions adopted, the time spent to accomplish tasks and the support asked.

Keywords:

Lab Experiments, Electronics, Differential Amplifier.