ISO7421FEDR

Overview

The ISO7421FEDR is a low-power, dual-channel digital isolator from Texas Instruments, housed in an SOIC-8 surface-mount package. It utilizes capacitive coupling technology to provide galvanic isolation with a rated insulation voltage of 2500 Vrms. The device supports unidirectional data transmission at a signaling rate of 50 Mb/s and features a typical propagation delay of 7 ns. Operating on supply voltages between 3.3 V and 5 V, it draws a typical operating current of 2.8 mA. The component functions within a temperature range of -40°C to +125°C and offers high common-mode transient immunity.

Feature Summary

• Provides galvanic isolation via capacitive coupling for noise reduction
• Supports bidirectional data flow across two independent channels
• Ensures signal integrity with low propagation delay characteristics

Applications

• Isolation between microcontrollers and line transceivers
• Data converter interface isolation
• General-purpose digital isolation in industrial systems

Procurement Notes

Verify the specific suffix 'F' indicates the default output state configuration, as this affects logic behavior upon power-up or fault conditions. Confirm the 'E' designation aligns with the required thermal performance grade for your application environment. Ensure the 'DR' suffix matches the reel packaging requirements for your assembly line equipment. Cross-reference the UL and VDE certification ratings against your system's safety compliance standards before finalizing procurement.

Selection Notes

Select this component when low power consumption is critical alongside moderate data rates. The SOIC-8 package suits space-constrained designs requiring standard surface-mount assembly. Consider the unidirectional nature of the channels when designing circuit topology. Evaluate the 2500 Vrms isolation rating against the maximum working voltage of your isolated boundaries. Compare the 50 Mbps speed against higher-speed alternatives if data throughput requirements exceed this limit.

Part Context

This part belongs to the ISO742x family of low-power dual-channel digital isolators. It shares core architectural similarities with variants like the ISO7421EDR but differs in specific electrical characteristics such as default output states and thermal grades. The family is designed to replace traditional transformer-based isolators in cost-sensitive and power-efficient applications.

Replacement Considerations

The ISO7421EDR serves as a functional substitute within the same series, sharing identical pinouts and core isolation specifications. Verify that the specific 'E' grade thermal and electrical parameters meet your design margins. Other ISO742x variants may require schematic adjustments due to differing channel configurations or speed capabilities.