Skyworks Solutions Inc. SI8660BB-AU

Overview

SI8660BB-AU from Skyworks is a six-channel, unidirectional digital isolator with 6 input channels on VDD1 side and 0 on VDD2 side, rated for 2.5 kVRMS isolation and operating from 2.5–5.5 V supply. It delivers 150 Mbps data rate, <10 ns propagation delay, and ultra-low power consumption (1.6 mA/channel at 1 Mbps, 5.5 mA/channel at 100 Mbps under 5 V), enabling robust signal isolation in high-noise industrial motor drives and battery management systems.

For engineers reviewing the SI8660BB-AU datasheet, SI8660BB-AU pinout, SI8660BB-AU application, or SI8660BB-AU equivalent, this page provides verified specifications, QSOP-16 package details, fail-safe low-default output configuration, AEC-Q100 automotive qualification, and real-world timing performance including 0.5 ns channel-channel skew and 50 kV/µs CMTI - all critical for isolated gate driver interfaces and safety-critical BMS designs.

Technical Context

The SI8660BB-AU implements RF-based on/off keying across a semiconductor isolation barrier, eliminating startup initialization and supporting DC–150 Mbps operation without external components beyond 0.1 µF bypass capacitors. Its Schmitt-trigger inputs provide high noise immunity, while independent undervoltage lockout (UVLO) on both sides ensures reliable behavior during asymmetric power sequencing.

It features selectable fail-safe mode (low default output, per ordering code), precise timing with ≤2 ns propagation delay skew and ≤1.5 ns pulse width distortion, and operates across –40 to +125 °C. All channels are unidirectional from VDD1 to VDD2, with no reverse-path capability.

Key Specifications

Pinout & Package

SI8660BB-AU is housed in a RoHS-compliant QSOP-16 package (5.3 mm × 10.2 mm, 1.0 mm height), optimized for space-constrained automotive and industrial PCBs with 0.635 mm pitch and creepage ≥5.5 mm.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar digital isolator applications.

Compared with SI8660BB-B-IU, SI8660BB-AU adds automotive process controls and documentation for production release; compared with ADUM6601ARWZ, it trades integrated power for smaller footprint and higher speed-making SI8660BB-AU optimal for space-limited, high-speed automotive signal isolation where external isolated supplies already exist.

Availability

SI8660BB-AU is available at Aetrix Electronics and suitable for automotive battery management systems, industrial motor drives, and isolated power supply designs requiring stable component supply, AEC-Q100 compliance, and long-term lifecycle continuity.

Supply support for SI8660BB-AU 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 leader in analog and mixed-signal semiconductors, specializing in RF, timing, and isolation technologies for wireless, automotive, and industrial markets.

The SI8660BB-AU belongs to Skyworks' Si86xx family of CMOS digital isolators, engineered specifically for high-reliability, low-power, high-speed signal isolation in automotive and industrial systems demanding AEC-Q100 qualification and reinforced safety certification.

FAQ

What is the default output state of SI8660BB-AU during input-side power loss?

The SI8660BB-AU is configured with a low-default fail-safe mode: when VDD1 is unpowered and VDD2 remains active, all six outputs (OUT1–OUT6) are driven low. This behavior is fixed by the "BB" ordering code and ensures safe deactivation of downstream gate drivers or relays in fault conditions. SI8660BB-AU does not support field-selectable fail-safe polarity.

Does SI8660BB-AU require external components for basic operation?

SI8660BB-AU requires only two 0.1 µF ceramic bypass capacitors-one between VDD1 and GND1, and another between VDD2 and GND2-placed adjacent to the QSOP-16 package. No pull-up/pull-down resistors, level shifters, or initialization firmware are needed. The device powers up with valid outputs within 40 µs and operates reliably across its full –40 to +125 °C range.

How does SI8660BB-AU achieve 50 kV/µs common-mode transient immunity?

SI8660BB-AU achieves 50 kV/µs CMTI through its RF-based modulation architecture and patented semiconductor isolation barrier, which rejects fast dV/dt transients without coupling into signal paths. This is validated per IEC 60747-17 test methods and exceeds typical optocoupler performance (typically 15–25 kV/µs), making SI8660BB-AU suitable for noisy environments like traction inverters and industrial VFDs.

Can SI8660BB-AU be used in medical equipment requiring IEC 60601-1 compliance?

Yes - SI8660BB-AU carries VDE 0884-10 and IEC 60601-1 reinforced insulation certification at 2.5 kVRMS, with documented creepage (≥5.5 mm) and clearance (≥4.5 mm) in QSOP-16. When implemented per Skyworks' layout guidelines (including separation of primary/secondary PCB regions), SI8660BB-AU supports Class II, Type CF medical isolation barriers in diagnostic and monitoring equipment.

What is the maximum ambient temperature rating for continuous operation of SI8660BB-AU?

SI8660BB-AU is rated for continuous operation from –40 °C to +125 °C ambient temperature, validated per AEC-Q100 Grade 1 requirements. Its junction temperature limit is 150 °C, and thermal performance remains stable across this range - confirmed by characterization data showing consistent propagation delay, skew, and supply current up to 125 °C.