Electronics Laboratory Practices: A Didactic ECG Signal Generator

In this paper we present the design and development of an didactic ECG signal generator to be implemented along with laboratory practices of an undergraduate basic electronics course, offered at FEEC/UNICAMP. The prototype produces ECG signals employing fundamental electrical circuits and concepts incorporated in the vast majority of medical equipment. It is evident, in the course of one of the greatest world health crisis in recent decades, the need for training qualified professionals (biomedical engineers) for the development of medical equipment. A good biomedical engineer does need to understand basic electronics, the human physiology and be able to design and construct simple and efficient electronics circuits often found in electromedical equipment. Our students had to cope with all expected program of the course content involving feedback, linear voltage regulators, operational amplifier topologies active filters, theoretical and practical aspects on signal amplification, digital-to-analog (D/A) and analog-to-digital (A/D) circuits and biological signal acquisition and processing. Although this paper shows only D/A circuits to construct a simple ECG signal generator, several other circuits can be built with the same methodology. The students have given us strong positive feedback. We noted very good results, both in the technical and motivational aspects with the students showing enthusiasm with great engagement and participation. We conclude that teaching electronics with practical problems is the best way to engage the students in the learning process.