ECG Interface Circuit Design for Improving The Quality of ECG Signal

A. S. Alkhader* Biomedical engineer with the Institute of Biomedical Technology at Royal Medical Services Amman, Jordan Aktham A. Alomar, Biomedical engineer with King Hussein Medical Center at Royal Medical Services Amman, Jordan Abdullah S. Althonaibat, Biomedical engineer with Prince Ali Hospital at Royal Medical Services Karak, Jordan Basma S. Hiyari Biomedical engineer with the Institute of Biomedical Technology at Royal Medical Services Amman, Jordan Mohammad A. Alshira'ah, Biomedical engineer with King Hussein Medical Center at at Royal Medical Services Amman, Jordan, Abstract: Over the years, many circuit designs were developed for detecting the electrical activity of the heart (ECG signal). The main aim was to reduce the noise and improving the efficiency and quality of the signal obtained from the heart. In this paper a suggested design of a single channel ECG circuit is introduced, it shows how to build the ECG circuit step by step, investigates the quality of the signal obtained after adding each stage of the circuit and offers a suggestions and ideas of the best circuit design and the best ICs that can be used to reduce the noises to get the best quality of ECG signal. This design is composed of the usual main parts which are instrumentation amplifier (IA), isolation circuit (iso-amp), band pass filter, and right leg circuit, in addition to a suggested first and second order band pass filter and a notch filter. The advantages of this design are its simplicity and high efficiency which represents in its ability to obtain a good quality signals with minimum noises, as it has many stages of filtration, in addition to its low cost which offers the opportunity to manufacture it in Jordan.