ISO122UE4

Overview

The ISO122UE4 is a precision isolation amplifier from Texas Instruments, utilizing duty cycle modulation-demodulation across a 2-pF differential capacitive barrier. It features a fixed unity gain configuration with a 50-kHz signal bandwidth and 140 dB common-mode rejection at 60 Hz. The device supports bipolar operation with ±10 V output swing and operates on supply voltages ranging from ±4.5 V to ±18 V. It offers 0.020% maximum nonlinearity and is rated for 1500 Vrms continuous isolation voltage. Available in an 8-lead SOIC package.

Feature Summary

• Galvanic isolation via digital transmission across a built-in capacitive barrier
• Fixed unity gain configuration requiring no external components
• High common-mode rejection ratio of 140 dB at 60 Hz
• Bipolar power supply operation supporting wide input/output ranges

Applications

• Transducer isolator applications
• Isolation for thermocouples, RTDs, pressure bridges, and flow meters
• 4-mA to 20-mA loop isolation
• Ground loop elimination
• Motor and SCR control systems

Procurement Notes

Verify the specific suffix 'E4' corresponds to the lead-free and RoHS-compliant version as documented by Texas Instruments. Confirm the package type matches the required 8-lead SOIC form factor. Ensure the operating temperature range aligns with the specified -25°C to 85°C limits for your application environment. Cross-reference the datasheet revision date to confirm current electrical characteristics and pinout definitions.

Selection Notes

Select this component when a cost-effective, high-reliability isolation solution with fixed unity gain is required. It is suitable for applications demanding high common-mode immunity and precise analog signal transmission across galvanic barriers. Consider the 50-kHz bandwidth limit for high-frequency signal integrity. Evaluate thermal resistance metrics if operating near maximum temperature limits or in enclosed spaces without adequate airflow.

Part Context

The ISO122 belongs to the ISO122 family of precision isolation amplifiers manufactured by Texas Instruments. This series utilizes a novel duty cycle modulation technique to transmit signals digitally across a capacitive barrier, ensuring excellent reliability and transient immunity. The family includes variants such as the ISO122U and ISO122P, differing primarily in packaging options like SOIC and PDIP.

Replacement Considerations

ISO122U/1K