This application note reviews data and provides recommendations for using Negative Temperature Coefficient (NTC) ring lug thermistors to monitor the temperature of a heat sink. The accuracy of an NTC-style ring lug and TMP6-style ring lug are compared with a Fluke® TiS60+ thermal imager. The findings discussed throughout this application note are summarized into a systems perspective for designers, providing design tradeoffs for ring lug thermistor applications.