Abstract
This study demonstrates a novel monolithic TPMS (Tire Pressure Monitoring Systems) using CMOS MEMS processes. This TPMS monolithic integrates the 3-axis capacitive accelerometer, capacitive pressure sensor, and Platinum (Pt) thermal-resist temperature sensor on a single chip. The TPMS has been successfully implemented using TSMC 2P4M process and our in-house post-process. The footprint of TPMS chip containing sensors and sensing circuits is 2.5mm x 2.5mm. Measurement results show that sensitivities of Tri-axis accelerometer etch direction are 0.54mV/G (X-axis), 0.32mV/G (Y-axis), and 0.19mV/G (Z-axis). The sensitivities of pressure and temperature sensors are respectively 2.7mV/ KPa and 1.74mV/ °C. ©2009 IEEE.