AD595ADZ

Overview

The AD595ADZ is a monolithic instrumentation amplifier and thermocouple cold-junction compensator designed for K-type (Chromel-Alumel) thermocouples. It integrates an ice-point reference with a pre-calibrated amplifier to produce a high-level output of 10 mV/°C directly from the thermocouple signal. The device operates on a single supply ranging from +5 V to +30 V, with typical power consumption under 1 mW. It features a high-impedance differential input to reject common-mode noise and includes a thermocouple open-circuit fault alarm with TTL drive capability. The component is housed in a 14-pin DIP package.

Feature Summary

• Integrated cold-junction compensation eliminates external reference requirements
• Pre-calibrated linear output matches K-type thermocouple characteristics
• Built-in fault detection alerts for thermocouple open circuits
• Supports setpoint control mode or independent Celsius temperature sensing

Applications

• Industrial process temperature monitoring systems
• HVAC equipment temperature control loops
• Scientific laboratory instrumentation requiring precise thermal measurement
• Automotive engine temperature sensing modules

Procurement Notes

Verify the specific suffix 'ADZ' confirms lead-free and RoHS compliance status as per manufacturer specifications. Confirm the package type corresponds to the standard 14-pin dual in-line configuration. Ensure the operating voltage range aligns with system power rails between 5 V and 30 V. Validate that the K-type calibration matches the installed thermocouple sensor type to prevent measurement errors.

Selection Notes

Select this component when direct amplification and compensation of K-type thermocouples are required without external circuitry. It is suitable for applications needing a linear voltage output proportional to temperature. Consider the wide operating temperature range for harsh environments. Evaluate the fault alarm feature if system reliability and open-wire detection are critical design parameters.

Part Context

This part belongs to the AD594/AD595 family of single-chip thermocouple amplifiers. While the AD594 is calibrated for J-type thermocouples, the AD595 is specifically tuned for K-type inputs. Both share similar architectures including cold-junction compensation and fault alarms, differing primarily in their internal gain calibration to match respective thermocouple voltage-temperature curves.

Replacement Considerations

• AD595ANZ

FAQ

Can the AD595ADZ be used with T-type thermocouples?

Yes, while pre-calibrated for K-type, it can be utilized with T-type thermocouples, though external scaling may be necessary for accurate readings.

What is the function of the fault alarm output?

The fault alarm detects an open thermocouple circuit and provides a TTL-compatible signal to indicate the failure condition.