I want to compare schematic with the other one

mems microphone stethoscope schematic

Abstract

This article is devoted to the investigation of MEMS microphone characteristics as an acoustic transducer of the electronic stethoscope. STMicroelectronics digital microphone MP45DT02 parameters were considered and significant physiological sounds were recorded. Also data obtained from MEMS and analog microphones were compared.The traditional acoustic stethoscope has been in use for nearly 200 years, changing very little over that time. As one of the most important diagnostic tools in a doctor’s repertoire, and comparatively low-tech by today’s standards, many recent attempts have been made to upgrade the design of the stethoscope. However, as they are at least twice the cost of traditional stethoscopes and produce a sound different from a traditional stethoscope, these electronic stethoscopes have had a hard time catching on. As such, our client requests a redesigned electronic stethoscope consisting of a main receiver box, with both speakers and a headphone jack for listening, along with two wireless microphones that attach to the patient and detect the heart and lung sounds. In order to effectively develop the prototype, a schematic of the design layout was developed, digital and analog amplifiers were compared, and two design matrices for microphone types and wireless technology were created. Based on research done into two different types of amplifiers, class – AB and class – D, class – AB was selected for its ease of implementation into our circuitry. After comparing three different types of microphones – condenser, fiber optic, and MEMS – it was determined that MEMS microphones were the best choice moving forward. For wireless technology, an FM transmitter, Bluetooth technology, and a PurePath wireless kit were researched. Based on our limited knowledge in dealing with the complexities of Bluetooth technology, the PurePath kit was chosen to implement the wireless capability of the prototype. Future work includes finalizing the design, ordering materials, assembling and testing the prototype, and performing final modifications based on client input and the tests results.