Silicon Labs introduced a new family of high-speed, multi-channel digital isolators designed to provide a complete, highly integrated solution for signal and power isolation. Silicon Labs' new Si88xx isolators feature an integrated dc-dc converter with 78 percent efficiency, deliver up to 2 W, and offer very low electromagnetic interference (EMI) emissions and high noise immunity. The Si88xx family reduces system cost, speeds time-to-market and enhances reliability for applications in harsh, noisy operating environments including factory automation, process control, programmable logic controllers (PLCs), solar inverters and automotive battery management.
Si88xx digital isolators provide up to 2 W of isolated power by harvesting power from the primary side to supply secondary side power. The isolators offer up to four high-speed digital isolation channels with excellent timing characteristics including low propagation delay and low jitter, enabling longer system lifetimes at high voltages. These signal isolation characteristics are critical for developers designing systems for industrial automation, battery management and motor control requiring long-term performance. The low-power, high-speed Si88xx digital isolation channels offer substantial data rate, propagation delay and reliability advantages over legacy isolation technologies including optocouplers. The Si88xx family supports data rates of up to 100 Mbps, and Si8xx devices achieve typical propagation delays of 23 ns.
The Si88xx isolators incorporate Silicon Labs' proven, patented digital isolator technology with an on-chip isolated dc-dc converter providing regulated output voltages of 3.3 V or 5.0 V (or >5 V with external components) at peak output power levels of up to 2 W. The robust dc-dc converter architecture, coupled with a ferrite core isolated transformer, provides ample power to self-power the secondary side of the isolator as well as other components such as RS-485 or CAN transceivers, microcontrollers and analog-to-digital converters (ADCs). The dc-dc converter is based on a modified fly-back architecture with secondary side sensing and feedback to the controller with external compensation. The power switches use zero voltage switching (ZVS) techniques to minimize power losses as well as dithering to minimize EMI.
Samples and production quantities of Si88xx digital isolators are available now in 20-pin WB SOIC packages. Ordering options include a choice of dc-dc converter features, isolation channel configurations and a fail-safe mode. All Si88xx products are certified by UL, CSA, VDE and CQC. Si88xx family pricing in 10,000-unit quantities begins at $2.42 (USD). To help developers evaluate the performance of Si88xx isolators, Silicon Labs' Si88xxxISO-KIT evaluation kit is available now for $29 (USD MSRP.