Design and implementation of a pressure sensor with piezoresistive technology in the automotive sector based on a new Sensor Signal Conditioner (ASIC)

In modern automotive systems, sensors are becoming increasingly numerous and play a very important role as they are able to ensure both performance and safety. This thesis presents the design and implementation of a pressure sensor employing a sensing element based on an existing and widely used piezoresistive technology, integrated with a new sensor signal conditioner (ASIC) from Renesas. This ASIC, the ZSSC4132, acquires the voltage signal from the sensing element, whose value varies with the pressure, converts it into a digital signal, processes it, and finally sends it out using the LIN protocol, a widely used communication protocol in the automotive industry. Additionally, it has the particularity of being able to acquire and process also signals from various temperature sensors. The first part, which is primarily theoretical, is dedicated to the analysis of piezore- sistive pressure sensors, the description of the operation of the ASIC, and the study of the LIN protocol. The practical part, largely carried out in the laboratory, is dedicated to the configuration of the LIN on the ASIC, the complete design of the PCB on which the ASIC is placed using an EDA tool, and the calibration of 5 pressure sensors. Various calibration methods were tested for each of these sensors, in order to obtain sufficient data to analyze and find the best method capable of generating the most accurate pressure readings. This work, in which the development of a new pressure sensor to be integrated into a LIN network is presented, is undoubtedly motivated by the growing need from automotive companies for cost-effective and high-performance sensors.