Introduction to Digital Stethoscopes and Electrical Component Selection Criteria

By: John DiCristina

Abstract: This application note provides an overview of the basic operation and design considerations for a digital stethoscope. The similarities between a digital stethoscope and an acoustic stethoscope, which is the older generation of the instrument, are explained. The article then outlines the more sophisticated features of the newer digital designs, including audio recording and playback. When discussing design considerations for a digital stethoscope, it details the importance of the audio signal path, presents considerations for audio codec electronics, and outlines the audio frequency requirements for cardiac and pulmonary sound. The article also addresses the system's subfunctions which include data storage and transfer, display and backlighting, power management, and battery management.