Silicon Labs introduces a new family of high-speed, multichannel digital isolators

     Silicon Labs has announced 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 isolator integrates a 78% efficient dc-dc converter and delivers up to 2W of power output, very low electromagnetic interference (EMI) and high noise suppression. The Si88xx series reduces system costs, reduces time to market, and increases reliability for applications that operate in harsh, noisy environments. These applications include factory automation, process control, programmable logic controllers (PLCS), solar inverters and automotive battery management.

     The Silicon Labs Si88xx isolator family addresses a critical need for plug-and-play isolated power supplies in industrial automation. Developers often need to design isolated power supplies from scratch, which can be a time-consuming, laborious and costly design process that requires the use of a large number of discrete devices. Discrete power solutions typically use field-effect transistors (FETs), controllers, single-channel isolators or photocouplers, and other devices. In contrast, the multichannel-based Si88xx isolator design requires only the addition of a miniature ferrite core transformer and several discrete passive devices. The solution based on the Si88xx isolator ultimately eliminates multiple design iterations, saves material (BOM) costs and reduces design complexity, while enhancing noise suppression and power efficiency.

     The Si88xx digital isolator provides up to 2W of isolated power to the secondary side by collecting electrical energy from the autonomous side. The isolator provides up to four high-speed digital isolation channels, combined with excellent timing characteristics such as low transmission delay and low jitter, resulting in a longer service life in high voltage environments. For applications such as industrial automation, battery management, and motor control that require long-term performance guarantees, these signal isolation features are critical for developers designing systems. The low-power, high-speed Si88xx digital isolation channel offers high data rates, low transmission latency, and reliability benefits that far exceed those of traditional isolation technologies, including optocouplers. The Si88xx family of products supports data rates up to 100Mbps and achieves the standard 23ns transmission latency.

     The Si88xx isolator uses Silicon Labs' proven proprietary digital isolator technology with an integrated on-chip isolated dc-dc converter to provide a regulated 3.3V or 5.0V output (or greater than 5V with off-chip device assistance) with peak output power of up to 2W. A reliable dc-dc converter architecture coupled with ferrite core isolation transformers provides sufficient power for self-powered isolators and other components such as RS-485, CAN transceivers, microcontrollers, and analog-to-digital converters (ADCs). The dc-dc converter is based on an improved fly-back architecture with side-side sensing capabilities and feeds back to a controller with external compensation. The power switch uses zero voltage switching (ZVS) technology to minimize power loss and jitter processing to minimize EMI.

     The Si88xx isolator has several safety features, including a built-in soft-start function to prevent inrush current, cycle-by-cycle current limiting capability, and thermal detection/shutdown. The integrated dc-dc converter includes built-in secondary sensing and feedback signals, eliminating additional optoelectronic feedback paths while enabling superior line and load regulation for better system stability. dc-dc converters also have a shutdown option and user-adjustable switching frequency, enabling precise EMI tuning to suit each developer's application needs.

     Ross Sabolcik, vice president and general manager of analog, Power and Sensor products at Silicon Labs, said, "The new Si88xx family of products delivers the superior EMI performance, high data rates and reliability provided by Silicon Labs digital isolator technology. Meet the needs of a wide range of applications in signal and power isolation and high channel density. "The Si88xx digital isolator provides industrial system developers with a complete, plug-and-play solution that greatly simplifies design in power applications while ensuring long-term performance and reliability."