Skyworks Solutions Inc. SI86SM42BC-IS1R

Overview

SI86SM42BC-IS1R from Skyworks Solutions is a four-channel reinforced digital isolator with two forward and two reverse signal paths, 6000 VRMS isolation rating, –40 to 125 °C operating temperature, and sleep mode control via SMb pin. It enables bidirectional data transfer across high-voltage barriers in isolated power supplies and motor drives.

For engineers reviewing the SI86SM42BC-IS1R datasheet, SI86SM42BC-IS1R pinout, SI86SM42BC-IS1R application, or SI86SM42BC-IS1R equivalent, key selection criteria include its 10 ns typical propagation delay, 150 Mbps data rate, AEC-Q100 qualification, and fail-safe output configuration (default low).

Technical Context

The SI86SM42BC-IS1R implements RF-based on/off keying modulation across a semiconductor isolation barrier, eliminating startup initialization and supporting DC–150 Mbps operation. Its architecture includes independent UVLO and reset circuitry per side (VDD1/VDD2), with RSTB thresholds at ~1.7 V and 100 kΩ weak pulldown during unpowered states.

Sleep mode is activated by driving the SMb pin low, reducing supply current to 750 µA per side while maintaining one active channel to monitor SMb status. The device supports selectable fail-safe output state (default low for this variant) and Schmitt-trigger + CMOS input thresholds for noise immunity.

Key Specifications

Pinout & Package

SI86SM42BC-IS1R uses a WB SOIC-16 package with 16-pin wide-body layout optimized for 6000 VRMS creepage and clearance. Pin numbering follows standard SOIC convention (pin 1 = top-left corner, counterclockwise).

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADUM2402BRWZ and ISO6742FDWR, SI86SM42BC-IS1R delivers 6× higher data rate, 20 ns faster propagation, 1000 VRMS higher isolation, and integrated sleep mode-making it optimal for next-generation EV chargers, high-fidelity motor drives, and medical imaging systems demanding precise timing and low standby power.

Availability

SI86SM42BC-IS1R is available at Aetrix Electronics and suitable for industrial motor control, automotive battery management, and isolated switch-mode power supplies requiring stable component supply and long-term lifecycle support.

Supply support for SI86SM42BC-IS1R 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 Si86S6xx/Lxx/Mxx/Qxx/Sxx family was designed for high-reliability isolation in automotive traction inverters, industrial automation, and medical electronics-emphasizing speed, safety certification, and low-power operation.

FAQ

What is the isolation voltage rating of the SI86SM42BC-IS1R?

The SI86SM42BC-IS1R has a reinforced isolation rating of 6000 VRMS for 1 minute per UL 1577, certified to IEC 60747-17, CSA 62368-1, and CQC GB4943.1. This rating applies specifically to the WB SOIC-16 package used in SI86SM42BC-IS1R and enables use in high-voltage industrial and automotive systems where creepage and clearance compliance is mandatory. The device maintains this rating across its full –40 to 125 °C operating range.

Does the SI86SM42BC-IS1R support fail-safe output behavior during power loss?

Yes, the SI86SM42BC-IS1R is configured as a default-low fail-safe variant. When VDD1 or VDD2 falls below UVLO thresholds, outputs transition to logic low-ensuring predictable, safe states in motor control shutdowns or BMS fault conditions. This behavior is implemented via internal circuitry and does not require external pull-down resistors. The SI86SM42BC-IS1R datasheet Table 4 confirms low-state output during unpowered conditions on either side.

How does the SMb pin function in the SI86SM42BC-IS1R?

The SMb pin on the SI86SM42BC-IS1R is an active-low sleep mode control input. Driving SMb low reduces total supply current to 750 µA per side while keeping one isolation channel active to monitor SMb status. When SMb is high or left floating, the device operates normally at full speed and drive strength. This pin is located on Side A (pin 5) and is validated in Figure 11 and Section 3.4.2 of the SI86SM42BC-IS1R datasheet.

What are the timing specifications for the SI86SM42BC-IS1R at 5 V supply?

At VDD1 = VDD2 = 5.0 V, the SI86SM42BC-IS1R achieves 10 ns typical propagation delay, 3.5 ns typical pulse width distortion, and supports DC–150 Mbps data rates. These values are measured under loaded conditions (CL = 15 pF) and are specified across –40 to 125 °C. The device maintains these specs without startup initialization, unlike optocoupler-based alternatives. All timing parameters are confirmed in Tables 9 and 10 of the SI86SM42BC-IS1R datasheet.

Is the SI86SM42BC-IS1R qualified for automotive applications?

Yes, the SI86SM42BC-IS1R is AEC-Q100 qualified for Grade 1 (–40 to 125 °C) operation and manufactured using automotive-specific process flows. It supports AIAG-compliant PPAP documentation, IMDS/CAMDS listings, and is approved for use in onboard chargers, battery management systems, and traction inverters. The "BC" in the part number denotes automotive-grade qualification, and the "IS1R" suffix indicates WB SOIC-16 packaging with tape-and-reel delivery.