AD694KR

Overview

The AD694KR is a monolithic current transmitter manufactured by Analog Devices Inc., designed to drive standard 4–20 mA current loops for process control applications. It accepts high-level voltage inputs, which are buffered and scaled by an internal amplifier. The device supports precalibrated input spans of 0 V to 2 V or 0 V to 10 V via pin strapping, with other ranges programmable using external resistors. It operates on a wide power supply range from 4.5 V to 36 V and features a precision voltage reference. The component is housed in a 16-lead CERDIP package and is rated for operation within a temperature range of -55 °C to +125 °C.

Feature Summary

• Monolithic integration of input buffering, scaling, and 4-20 mA loop driving capabilities
• Precision internal voltage reference supporting accurate signal transmission
• Flexible input configuration allowing selection between 0-2 V and 0-10 V spans through simple pin connections
• Wide operating supply voltage range suitable for single or dual supply systems

Applications

• Driving valves and actuators in industrial process control systems
• Transmitting sensor signals over standard 4-20 mA current loops
• Buffering output from current mode digital-to-analog converters (DACs)
• Factory automation and system monitoring requiring precise signal isolation

Procurement Notes

Verify the specific suffix KR indicates the military-grade ceramic DIP variant when sourcing. Confirm availability status as some ADI components may be subject to limited distribution or end-of-life notices. Ensure the supplier provides official documentation matching the exact part number to avoid confusion with commercial plastic packages like AR or BR.

Selection Notes

Select the AD694KR for applications requiring extended temperature stability and ruggedness compared to commercial variants. Verify that the required input span matches the available pin-strapped options or confirm resistor programming feasibility. Check if the 16-lead CERDIP package fits the mechanical constraints of the target design, considering alternatives like SOIC if space is limited.

Part Context

The AD694 series serves as a dedicated solution for converting voltage signals into standardized current loops. The KR suffix typically denotes a higher reliability grade, often associated with military or aerospace specifications, distinguishing it from the standard commercial AD694 versions. This component simplifies the design of isolated transmitters by integrating necessary amplification and reference circuits on a single chip.