Low Cost Analogue Front End for Electronic Stethoscopes Application with Silicone Enclosure

Traditional stethoscopes have remained virtually unchanged for nearly 200 years and remain the primary examination tool for all medical practitioners. While their use is prominent, their single user design and susceptibility to noise distortions can result in loss of critical diagnostic information. With the rise of cardiovascular disease worldwide, a shift for more effective tools in practitioner's repertoire is needed to ensure accurate and quick diagnosis is made. This can be achieved with the implementation of an Electronic Stethoscope using a single low-cost front-end sensing unit with integrated pre-amplifier and filter to rival some commercially available sensors that are high cost. A piezoelectric sensor was used cast in a two different domed silicone enclosure to protect the unit and provide better acoustical transmittance of the sounds generated from the human body. The results collected form the carotid artery showed that a simple, yet effective electronic design with final cost of .20 AUD-could produce good quality signals of both systole and diastole which could then be processed in MATLAB to increase bodily sounds volume and enable use of this tool in the field. This paper presents the preliminary work limited to the analogue front-end.