Two-channel, K-type thermocouple measurement circuit with internal temperature

Texas Instruments

Published Date: 14 Jan 2019


This cookbook design describes a temperature measurement circuit with two thermocouples using the ADS1118. Thermocouple voltage measurements are made with the ADS1118 internal voltage reference, while cold-junction compensation (CJC) measurements are made with the onboard temperature sensor. Two channels of the ADC are used for two K-type thermocouples with a temperature measurement range from –270°C to 1370°C. Included in this design are ADC register settings to configure the device and pseudo code is provided to configure and read from the device. This circuit can be used in applications such as analog input modules for PLCs, lab instrumentation, and factory automation.


Part Number Name Companion Part
ADS1118IRUGR ADS1118IRUGR Buy Datasheet
ADS1118IDGST ADS1118IDGST Buy Datasheet
ADS1118IDGSR ADS1118IDGSR Buy Datasheet
ADS1118IRUGT ADS1118IRUGT Buy Datasheet
ADS1118QDGS Q1 ADS1118QDGS Q1 Buy Datasheet
ADS1118I UGT ADS1118I UGT Buy Datasheet
ADS1118I UG ADS1118I UG Datasheet
ADS1118IDGS ADS1118IDGS Buy Datasheet
ADS1118QDGSRQ1 ADS1118QDGSRQ1 Buy Datasheet
ADS1118EVM ADS1118EVM Buy Datasheet