Nonintrusive Current-Sensing Using TMR Technology

This technical report provides a comprehensive comparison of current-sensing technologies, focusing on tunnel magnetoresistance (TMR) sensors, sense resistors, Hall-effect sensors, and current transformers. It outlines the advantages and limitations of each technology, emphasizing the features of the Allegro CT100 linear TMR sensor. The report begins by discussing the increasing demand for accurate and cost-effective current sensors and the challenges faced by circuit designers in selecting appropriate technologies. It details the operational principles of TMR technology and its applications in various fields, including hard drives and magnetic sensors. The report presents a comparative analysis of different current-sensing methods, highlighting their accuracy, isolation, power consumption, and cost. The CT100 sensor is described as a nonintrusive device with high linearity and low power draw, making it suitable for a range of applications. The document concludes by noting the growing momentum of TMR technology in the semiconductor industry and its potential to meet evolving design needs.