Skyworks Solutions Inc. SI88221EC-ISR

Overview

SI88221EC-ISR from Skyworks Solutions is a dual-channel digital isolator with integrated isolated DC-DC converter, delivering up to 2 W of regulated 3.3 V or 5.0 V output power across 5 kVRMS isolation. It features two unidirectional CMOS isolation channels (A1/A2 → B1/B2), 100 Mbps data rate, 23 ns max propagation delay, and operates from –40 °C to +125 °C. It is used in industrial motor control systems requiring reinforced insulation and compact isolated power.

For engineers reviewing the SI88221EC-ISR datasheet, SI88221EC-ISR pinout, SI88221EC-ISR application, or SI88221EC-ISR equivalent, this page provides verified technical context, SOIC-16 wide-body package details, automotive-grade AEC-Q100 qualification, safety certifications (UL 1577, VDE 62368-1), and validated alternative options for isolated signal and power delivery in high-noise environments.

Technical Context

The SI88221EC-ISR implements RF-based on/off keying modulation across a silicon dioxide capacitive barrier, enabling robust noise immunity and eliminating startup initialization. Its digital channels operate independently with precise timing-18 ns typical propagation delay and 0–100 Mbps data rate support.

The integrated DC-DC controller uses peak current mode control with closed-loop feedback via VSNS/COMP pins, supporting low-voltage configurations (3–5.5 V input to 3/5 V output) and featuring soft-start (SS pin), shutdown (SH pin), and internal power switches (VSW). It achieves 83% peak efficiency with external power switch and delivers up to 5 W peak isolated power.

Key Specifications

Pinout & Package

SI88221EC-ISR is housed in a RoHS-compliant SOIC-16 wide-body package (10.3 mm × 10.3 mm, 2.3 mm height) with creepage/clearance ≥8.3 mm, optimized for reinforced insulation in high-voltage systems.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel isolated DC-DC applications.

Compared with ADUM6210ARWZ and ISO7821FDWR, SI88221EC-ISR uniquely integrates 2 W isolated power with 100 Mbps signaling in a single SOIC-16 package, reducing system-level component count and simplifying certification for IEC 61800 and ISO 26262 applications.

Availability

SI88221EC-ISR is available at Aetrix Electronics and suitable for industrial motor drives, automotive battery management systems, and programmable logic controllers requiring stable component supply, long lifecycle assurance, and AEC-Q100-compliant sourcing.

Supply support for SI88221EC-ISR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Skyworks Solutions is a global semiconductor company specializing in analog and mixed-signal connectivity solutions, with leadership in RF, timing, and isolation technologies.

The Si88x2x product line was designed to replace optocouplers and discrete isolator + DC-DC combinations in high-reliability industrial and automotive systems demanding integrated signal and power isolation.

FAQ

What is the maximum data rate supported by SI88221EC-ISR?

The SI88221EC-ISR supports a maximum data rate of 100 Mbps across both isolation channels. This is confirmed in the Skyworks datasheet Section 1 and Table 1, where "0 to 100 Mbps" is specified for all Si8822x devices. The actual achievable rate depends on PCB layout, load capacitance, and signal integrity - but the device guarantees full functionality up to 100 Mbps under standard operating conditions. SI88221EC-ISR maintains sub-23 ns propagation delay even at this rate.

Does SI88221EC-ISR provide isolated power, and what are its output capabilities?

Yes, SI88221EC-ISR integrates an isolated DC-DC converter capable of delivering up to 2 W average (5 W peak) output power at either 3.3 V or 5.0 V. It supports low-voltage configurations (3–5.5 V input to 3/5 V output) using internal switches (VSW), and requires only a miniature transformer, rectifier diode, and minimal passive components. The output voltage is set via a resistor divider on the VSNS pin. SI88221EC-ISR does not support >5.5 V outputs without external regulator circuitry.

What safety certifications apply to SI88221EC-ISR?

SI88221EC-ISR is certified to UL 1577 (5000 VRMS, 1 min), CSA 62368-1, VDE 62368-1, and CQC GB4943.1. These approvals cover reinforced insulation for industrial and automotive end equipment. The device also meets AEC-Q100 Grade 1 qualification for automotive use and exhibits 100 kV/µs typical common-mode transient immunity - critical for noise-prone motor drive and inverter applications. All certifications are explicitly listed in the Skyworks datasheet Section "Safety Regulatory Approvals".

How is shutdown controlled on SI88221EC-ISR?

Shutdown is controlled via Pin 6 (SH), which disables the integrated DC-DC converter when driven high. In normal operation, SH must be tied to GNDA (ground). This feature allows system-level power sequencing - for example, disabling isolated power during MCU reset or fault conditions. The SH function is documented in Section 2.3.1 of the datasheet and applies specifically to Si882xx variants like SI88221EC-ISR; it is not present on Si884xx/Si886xx (which use SH_FC instead).

What package type and footprint does SI88221EC-ISR use?

SI88221EC-ISR uses a SOIC-16 wide-body package (10.3 mm × 10.3 mm, 2.3 mm height) with creepage and clearance distances ≥8.3 mm - sufficient for reinforced insulation per IEC 62368-1. The pinout matches Figure 1 (Si88221) in the datasheet: Pins 1–6 are primary-side (VDDP, VSW, GNDP, VDDA, GNDA, SH), Pins 7–10 are signal I/O (A1, A2, B1, B2), and Pins 11–16 are secondary-side (GNDB, VDDB, VSNS, COMP, NC, NC). No thermal pad or exposed paddle is present.