
Here’s an application note from Maxim on triple remote temperature sensor:
The MAX31730 temperature sensor monitors its own temperature and the temperatures of three external diode-connected transistors. The operating supply voltage is from 3.0V to 3.6V. Resistance cancellation compensates for high series resistance in circuit-board traces and the external thermal diode, while beta compensation corrects for temperature-measurement errors due to low-beta sensing transistors.
All temperature channels have programmable temperature thresholds. When the measured temperature of a channel crosses the respective threshold, a status bit is set in the thermal status registers and the open-drain THERM output asserts. A highest temperature register allows the master to obtain the temperature of the hottest channel.
