At Sensors Expo 2018, Mike Mays from Analog Devices explains the LTC2983, a temperature to bits IC. The IC is designed to be an extremely easy to use part. Everything necessary to measure temperature is performed by the chip and its output is in direct degrees C. In the display, an “EMI (electromagnetic interference) Hairball from Hell,” a rat’s nest of interfering electronic/electrical noise sources, simulates and injects the types of interference that could be encountered in an industrial environment including a vacuum, chainsaw, circular saw, Christmas lights and LED light.
Using a temperature calibrator that creates the equivalent signal from a resistance to temperature device (RTD) for a selected temperature, the display sends that signal through 1000 feet of unshielded telephone wire through the EMI maze and outputs it into the chip, an LTC2986, a variant from the family. With 300°C sent from the temperature calibrator, the IC reads 300.05°C to provide an extremely accurate reading. Dropping the calibrator’s temperature to 200°C results in a reading of 200.05°C even when all of the interference from the various EMI sources is applied.
The LTC2983, LTC2984 and LTC2986 are Multi-Sensor High Accuracy Digital Temperature Measurement System ICs that directly digitize RTDs, thermocouples, thermistors and diodes. They report results in °C or °F for up to 20 flexible inputs allowing interchanging sensors. In addition to having automatic thermocouple cold junction compensation, the ICs have a built-in standard and user-programmable coefficients for thermocouples, RTDs and thermistors.
The DC2296A demo board and DC2296A-KIT starter kit are available for the LTC2983.