1B51BN

Overview

The ADI 1B51BN is an isolated millivolt and thermocouple signal conditioner designed for industrial process control applications. It provides high-accuracy signal conditioning with galvanic isolation between input, output, and power terminals. The device accepts standard thermocouple inputs (J, K, T, E, R, S, B) or low-level DC voltage signals. Key electrical parameters include a typical accuracy of ±0.1% of full scale, a common-mode rejection ratio (CMRR) exceeding 120 dB at 60 Hz, and an isolation voltage rating of 1500 Vrms. It operates from a single 24 VDC supply and delivers a proportional 4–20 mA current loop output.

Feature Summary

• Galvanic isolation separates input, output, and power circuits to protect against ground loops and high-voltage transients.
• Integrated cold junction compensation ensures accurate thermocouple measurements without external sensors.
• Configurable linearization supports multiple thermocouple types and direct mV input ranges.

Applications

• Industrial process monitoring and control systems
• Temperature measurement in manufacturing environments
• Data acquisition systems requiring isolated sensor interfaces

Procurement Notes

Verify the specific suffix 'BN' corresponds to the PDIP-8 package variant when sourcing. Confirm that the required thermocouple type configuration matches the factory-set or field-configurable options available for this specific revision. Ensure isolation voltage ratings meet the safety requirements of the target installation environment before finalizing procurement.

Selection Notes

Select the 1B51BN when high accuracy and robust isolation are required for thermocouple or mV signals. Compare against non-isolated alternatives if cost is the primary constraint, noting that isolation adds protection against ground loops. Verify that the 4–20 mA output load capability meets the impedance requirements of the receiving PLC or controller input circuitry.

Part Context

The 1B51 series belongs to Analog Devices' family of isolated signal conditioners, which also includes models for RTD, strain gauge, and general voltage inputs. These devices are engineered to bridge the gap between raw sensor data and digital control systems, providing necessary signal scaling and noise rejection in electrically noisy industrial settings.

Replacement Considerations

Publicly confirmed substitute part numbers for the 1B51BN are not available in the provided documentation. Cross-referencing with other isolated signal conditioners requires verifying pin compatibility, isolation voltage ratings, and output linearity specifications manually.