7 Summary

This application note showed a method for assessing thermal performance of in-package magnetic current sensors. The first step of the method entailed sweeping a TMCS1100 with no load across temperature and determining the junction voltage to junction temperature relationship. The second step required at least two junction and case measurements for different loads be obtained to determine the junction and case temperature relationship when the device is powered off and isolated from the system supply and ground. The measurement data showed that the relationship is linear and could subsequently be used to calculate junction temperatures based upon case temperatures. This method relied on case measurements through a thermocouple. This application report discussed several of the subtle setup variables that can influence the accuracy of the thermocouple measurement. These variables were important for procuring the results observed in this report and will be important for any similar thermal assessment of the TMCS1100 involving a thermocouple.