Digital isolators rated to 5-kV

July 29, 2011 // By Phil Ling
A family of digital isolators from Silicon Labs is said to offer the highest channel count, performance and data rate for demanding applications with isolation ratings up to 5kV. The Si86xx 3.75kV and 5kV digital isolators are intended to replace optocouplers in applications requiring high levels of insulation protection, such as industrial automation and drives, motor control and medical systems.

With its 5kV rating, the Si86xx family provides isolation for systems powered from 220 Vac mains supplies such as isolated ac-dc and dc-dc power supplies, as well as solar panel microinverters, data communications systems and hybrid electric vehicles (HEVs).

Based on Silicon Labs’ patented digital isolation technology, the new family includes what it claims is the industry’s first six-channel isolators rated to 5kV, bidirectional isolators suitable for isolating I2C buses in a wide range of applications, and 3.75kV options that provide higher levels of protection than currently available from 2.5kV isolators.

These higher isolation ratings translate into a longer service lifetime in harsh application conditions. The Si86xx family’s unmatched isolation channel count also helps simplify timing and isolation challenges in high-speed systems with wide digital buses by enabling developers to minimize the number of separate isolators, thereby reducing BOM costs and board space.

The Si86xx family offers significant electromagnetic emissions and immunity performance advantages, providing error-free data in noisy environments and up to 20 dB lower electromagnetic emissions than competing solutions. By offering the highest electric field immunity, the Si86xx digital isolators are well suited for use in noisy environments common in motor control, industrial automation and power supply applications as well as green energy applications such as smart meters where tamper protection is a growing concern.

The Si86xx isolators are also said to deliver the industry’s fastest data rate (150Mbps) across the widest temperature range (-40 to 125ºC), as well as ultra-low power operation of less than 1.6mA per channel at 1Mbps for energy-efficient system design. The robust architecture of the Si86xx family is said to ensure signal integrity is maintained even while operating at high data rates and at high temperatures in harsh environments.

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