Electromagnetic Noise Mitigation for Ultrafast on-Die Temperature Sensing in High-Power Modules

Real-time junction temperature measurements can be very beneficial for improving power converter's design, performance, and reliability. Junction temperature sensing using an on-die diode sensor is a promising solution. However, a strong low-pass filter is usually applied to filter out the sensor's noise during switching transients, which reduces the sensor's bandwidth. This paper aims to improve the sensing system's bandwidth to achieve an ultrafast real-time junction temperature measurement. Three noise coupling mechanisms have been identified and verified by both simulations and experiments. The noise coupling model-based crosstalk capacitances estimation method is proposed and validated. Noise mitigation methods are proposed, thus only a 200-kHz low-pass filter is needed for the noise suppression purpose, which is a significant improvement from the current field implementation of tens of hertz bandwidth.