AD8494ARMZ

Overview

The AD8494ARMZ is a precision thermocouple amplifier designed for J-type thermocouples, featuring integrated cold junction compensation. It provides a linear output of 5 mV/°C with an initial accuracy of ±1°C and ambient temperature rejection of 0.025°C/°C. The device operates on a single supply voltage ranging from 2.7 V to 36 V or dual supplies of ±2.7 V to ±18 V, drawing a quiescent current of 180 μA. It utilizes an 8-lead MSOP package and includes high impedance differential inputs with overvoltage protection up to VS ± 25 V.

Feature Summary

• Integrated cold junction compensation using an internal temperature sensor
• High common-mode rejection ratio to suppress noise on long thermocouple leads
• Robust input protection against electrostatic discharge and overvoltage conditions
• Reference pin allows for offset adjustment and setpoint control functionality

Applications

• J-type thermocouple temperature measurement systems
• Setpoint controllers for industrial heating applications
• Standalone Celsius thermometer implementations
• Universal cold junction compensator circuits

Procurement Notes

Verify the specific ordering suffix to ensure the correct packaging configuration matches system requirements. Confirm that the component meets all necessary regulatory compliance standards for the intended deployment environment. Cross-reference the manufacturer's latest documentation to validate availability status before finalizing procurement plans.

Selection Notes

Select this component when utilizing J-type thermocouples within an ambient temperature range of 0°C to 50°C. Ensure the application requires a fixed gain of approximately 96.7 to achieve the standard 5 mV/°C output sensitivity. Verify that the power supply constraints align with the specified wide operating voltage range for optimal performance.

Part Context

This part belongs to the AD849x family of precision thermocouple amplifiers manufactured by Analog Devices Inc. The series includes variants optimized for both J-type and K-type thermocouples, differentiated by their laser-wafer trimming characteristics. These devices are engineered to simplify signal conditioning by combining amplification and compensation in a single integrated circuit package.

Replacement Considerations

The AD8496ARMZ serves as a direct functional substitute within the same family, offering identical specifications but calibrated specifically for J-type thermocouples with an optimized ambient temperature range of 25°C to 100°C.