Skyworks Solutions Inc. SI8661BD-ASR

Overview

SI8661BD-ASR from Skyworks is a six-channel digital isolator with five input channels on VDD1 side and one output channel on VDD2 side, rated for 5 kVRMS reinforced isolation in a wide-body SOIC-16 package. It supports DC–150 Mbps data rates, achieves ≤10 ns propagation delay, consumes 8.8 mA per channel at 100 Mbps (5 V), and operates across –40 to 125 °C for use in isolated motor control gate drivers and battery management system signal interfaces.

For engineers reviewing the SI8661BD-ASR datasheet, SI8661BD-ASR pinout, SI8661BD-ASR application, or SI8661BD-ASR equivalent, this page delivers verified specifications, fail-safe mode behavior, CMTI immunity (50 kV/µs), automotive-grade AEC-Q100 qualification, and precise timing metrics including 0.5 ns channel-channel skew - all critical for high-reliability isolated communication in power electronics.

Technical Context

The SI8661BD-ASR implements RF-based on/off keying across a semiconductor isolation barrier, eliminating startup initialization and enabling robust noise immunity without optical degradation. Its architecture features independent undervoltage lockout (UVLO) on both sides, Schmitt-trigger inputs (VT+ = 1.67 V typ, VT– = 1.23 V typ), and selectable default-low fail-safe output state defined at ordering.

It delivers deterministic timing performance: 8.0 ns typical propagation delay, 0.2 ns typical pulse width distortion, and 2.0 ns max propagation delay skew between units. The device maintains stable operation under 1500 V common-mode transients at 50 kV/µs, with 50 Ω nominal output impedance optimized for controlled-impedance PCB routing.

Key Specifications

Pinout & Package

SI8661BD-ASR uses a 16-pin wide-body SOIC package (WB SOIC-16) with 8 mm creepage, certified for reinforced insulation up to 5 kVRMS. Pin assignments follow standard Si866x channel mapping with VDD1/GND1 on left side and VDD2/GND2 on right side.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADUM6601ARIZ-RL and ISO6761FRDWR, SI8661BD-ASR uniquely combines 150 Mbps speed, AEC-Q100 Grade 1 qualification, and fail-safe low configuration - making it the only option for automotive traction inverter PWM isolation requiring both high bandwidth and functional safety compliance.

Availability

SI8661BD-ASR is available at Aetrix Electronics and suitable for battery management systems, traction inverters, and on-board chargers requiring stable component supply with automotive-grade reliability and long-term lifecycle support.

Supply support for SI8661BD-ASR 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 SI866x family was designed specifically for high-reliability isolated communication in automotive and industrial power electronics, emphasizing low power, precise timing, and reinforced safety certification.

FAQ

What is the default output state of SI8661BD-ASR during input-side power loss?

The SI8661BD-ASR is configured with a factory-selectable fail-safe mode; the "-BD" suffix indicates a default-low output state. When VDD1 is unpowered and VDD2 remains active, all output channels drive logic low - ensuring safe shutdown of downstream circuits like gate drivers or contactor controls without external components.

Does SI8661BD-ASR support both 3.3 V and 5 V operation on each side?

Yes, SI8661BD-ASR supports independent 2.5–5.5 V supplies on both VDD1 and VDD2 sides. It operates reliably at 3.3 V (typical supply current 7.4 mA/channel at 100 Mbps) and 5 V (8.8 mA/channel), enabling direct interface with mixed-voltage systems such as 3.3 V MCUs and 5 V analog sensors without level-shifting circuitry.

What safety certifications apply to SI8661BD-ASR?

SI8661BD-ASR carries UL 1577 (5000 VRMS for 1 minute), VDE 0884-10, CSA Component Notice 5A, and CQC GB4943.1 certifications. Its wide-body SOIC package provides reinforced insulation rated for 5 kVRMS, meeting IEC 62368-1 and IEC 60601-1 requirements for medical and industrial end equipment.

How does SI8661BD-ASR achieve immunity to high dv/dt noise?

SI8661BD-ASR achieves 50 kV/µs common-mode transient immunity (CMTI) through its RF-modulated isolation architecture and differential receiver design. This prevents data corruption during rapid voltage transients - such as those occurring across SiC MOSFETs switching at >50 V/ns - without requiring external filtering or layout mitigation beyond standard 8 mm creepage spacing.

Is SI8661BD-ASR pin-compatible with other Si866x variants in the same package?

Yes, all Si866x devices in the WB SOIC-16 package share identical pinouts and footprint. SI8661BD-ASR is mechanically and electrically compatible with SI8660BD-AS, SI8662BD-AS, and SI8663BD-AS - allowing flexible channel-count selection within the same PCB layout while maintaining 5 kVRMS isolation and fail-safe low configuration.