ISO7821LLDW

Overview

The ISO7821LLDW is a dual-channel digital isolator from Texas Instruments, utilizing capacitive coupling technology to provide electrical isolation between circuits. It operates within a supply voltage range of 2.25 V to 5.5 V and supports data rates up to 100 Mb/s. The device features a unidirectional signal path with two independent channels. Key electrical specifications include an insulation voltage of 5700 Vrms, a common-mode transient immunity of 100 kV/µs, and a maximum propagation delay of 25 ns. It functions reliably across an extended temperature range from -55°C to +125°C.

Feature Summary

• Provides robust galvanic isolation via capacitive coupling technology for noise immunity
• Supports high-speed data transmission at rates up to 100 Mb/s
• Features unidirectional signal flow for simplified interface design
• Ensures signal integrity with high common-mode transient immunity

Applications

• Isolating microcontrollers in industrial communication networks
• Protecting gate drivers in power electronics systems
• Signal isolation in medical equipment interfaces
• Digital isolation for sensor interfaces in harsh environments

Procurement Notes

Verify the specific suffix against official documentation, as package variations exist within the family. Confirm that the 'DW' designation corresponds to the SOIC-16 tube packaging rather than the 'DWR' tape-and-reel variant. Ensure compliance with RoHS directives and check humidity sensitivity levels prior to surface-mount assembly processes.

Selection Notes

Select this component when unidirectional isolation is required for LVDS or general digital signals. It is suitable for designs needing 5700 Vrms isolation with low power consumption. Consider the SOIC-16 footprint constraints and thermal dissipation requirements. Compare against higher-speed variants if data rates exceed 100 Mb/s are necessary.

Part Context

This part belongs to the ISO7821LL series of digital isolators. It shares the same core isolation architecture as other members but differs in speed and configuration. The series is designed for applications requiring reliable signal transfer across isolation barriers without magnetic components.

Replacement Considerations

ISO7821LLDWR offers identical electrical performance but in tape-and-reel packaging. ISO7821LLSDWR provides higher speed capabilities (150 Mb/s) in similar packages.