Optimization of Temperature Sensor Placement in Multi-Chip Power Modules Using Frequency Domain Analysis

Accurate real-time temperature measurement is crucial for monitoring power modules, particularly in critical applications. Embedded temperature sensors, such as negative-temperature coefficient (NTC) thermistors, are commonly utilized for this purpose. The arrangement of these sensors plays a pivotal role, as the accuracy of measurements relies on their placement. This paper presents a new methodology for optimally placing temperature sensors in multi-chip power modules for improved temperature estimation. The optimum sensor arrangement is achieved by introducing the frequency bandwidth as a new optimization parameter and maximizing it based on the number of sensors. The efficacy of this methodology is demonstrated using one multi-chip power module, and the optimal sensor locations are validated for average temperature over an actual mission profile. Compared to the original NTC location, significant improvements are observed at the predicted optimal locations.