ISO7421FED

Overview

The ISO7421FED is a low-power, dual-channel digital isolator from Texas Instruments, housed in an SOIC-8 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 rates up to 50 Mb/s. Operating on a supply voltage range of 3.3 V to 5 V, it draws a typical operating current of 6 mA per channel. Key electrical characteristics include a propagation delay of 7 ns and a power dissipation of 138 mW. It functions reliably within an industrial temperature range of -40°C to +125°C.

Feature Summary

• Provides robust galvanic isolation between circuits using capacitive coupling technology.
• Enables high-speed bidirectional data communication with low power consumption.
• Supports standard logic levels across a wide supply voltage range.

Applications

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

Procurement Notes

Verify the specific suffix 'FED' corresponds to the SOIC-8 tube packaging configuration. Confirm that the required insulation voltage rating of 2500 Vrms meets system safety standards. Ensure the 50 Mb/s data rate is sufficient for the target application's timing requirements before finalizing procurement.

Selection Notes

Select this component when a balance of moderate speed (50 Mb/s) and low power consumption is required. It is suitable for applications where a 2500 Vrms isolation barrier is adequate. Consider the SOIC-8 footprint constraints and the 6 mA quiescent current draw against available power budgets compared to higher-speed or lower-current alternatives.

Part Context

This part belongs to the ISO742x family of low-power dual-channel digital isolators. It shares the same core architecture as the ISO7420 but offers higher data rate capabilities. The series is designed for general-purpose isolation tasks, providing a compact solution for breaking ground loops and protecting sensitive electronics in noisy environments.

Replacement Considerations

The ISO7420FED is a related variant within the same family offering similar functionality but potentially different performance specifications. Verify pinout compatibility and electrical parameter alignment before substituting.