AD8497CRMZ

Overview

The AD8497CRMZ is a precision thermocouple amplifier with integrated cold junction compensation, optimized for K-type thermocouples. It provides a linear output of 5 mV/°C directly proportional to the measurement junction temperature. The device operates on a single supply ranging from 2.7 V to 36 V or dual supplies of ±2.7 V to ±18 V. Initial accuracy is specified at ±1.5°C within an ambient temperature range of 25°C to 100°C. Quiescent current is typically 180 μA. The component features high impedance differential inputs and overvoltage protection up to VS ± 25 V.

Feature Summary

• Integrated cold junction compensation eliminates external reference sensor requirements
• Laser-wafer trimmed for direct K-type thermocouple signal conditioning
• High common-mode rejection ratio blocks noise on long thermocouple leads
• Robust input protection withstands overvoltage conditions relative to supply rails

Applications

• Exhaust gas temperature sensing in automotive systems
• Temperature measurements in white goods such as ovens and stovetops
• Catalytic converter temperature monitoring
• Universal cold junction compensator circuits

Procurement Notes

Verify the specific ordering suffix against manufacturer documentation to confirm package type and temperature grade. Ensure the selected variant matches the required ambient operating range for the intended application environment before finalizing procurement.

Selection Notes

Select this model when measuring K-type thermocouples in environments where ambient temperatures range between 25°C and 100°C. For applications requiring operation near room temperature (0°C to 50°C), consider the AD8495 variant instead. Verify that the supply voltage supports the required output swing for the target temperature range.

Part Context

This component belongs to the AD849x family of precision thermocouple amplifiers manufactured by Analog Devices. The family includes variants optimized for J-type and K-type thermocouples with different ambient temperature ranges. The AD8497 specifically targets higher ambient temperature environments compared to the AD8495.

Replacement Considerations

The AD8495CRMZ serves as a functional substitute for K-type thermocouple applications but is optimized for a 0°C to 50°C ambient range rather than the 25°C to 100°C range of the AD8497.