A TMR-based Integrated Current Sensing Solution for WBG Power Modules

This paper proposes a contactless and high-precision current measurement solution using Tunneling Magnetoresistance (TMR) sensors to address the challenges of current measurement in wide band gap (WBG) power electronics with high dv/dt, di/dt and switching frequencies. The solution, referred to as TTS, utilizes two TMR sensors placed on opposite sides of the current-carrying trace or PCB-based terminal. By differentiating the sensor readings, the system achieves enhanced resolution and reduced errors from external magnetic fields and temperature fluctuations. Notably, the Two TMR Sensor (TTS) implementation is compatible with various power module designs, requiring no modification during fabrication, and seamlessly can be integrated into the final stages. Overall, this novel current measurement solution offers significant advantages for improved performance in power modules.