Skyworks Solutions Inc. SI83405BDA-IFR

Overview

SI83405BDA-IFR from Skyworks Solutions is a single-channel isolated high-side smart switch with 1.5 kVRMS galvanic isolation, 2.5 A continuous output current (RON = 41 mΩ), SPI interface for diagnostics, and operation across 9 V–32 V switch supply and 2.25 V–5.5 V logic supply. It drives industrial inductive loads such as solenoids and relays in PLC I/O modules.

For engineers reviewing the SI83405BDA-IFR datasheet, SI83405BDA-IFR pinout, SI83405BDA-IFR application, or SI83405BDA-IFR equivalent, key selection considerations include its SPI-only control architecture, absence of channel status indicators or fault warning pins, 10 µs update rate, CMTI > 100 kV/µs, and compliance with IEC 61131-2 for programmable controller interfaces.

Technical Context

The SI83405BDA-IFR implements RF-based CMOS isolation between logic and power domains, enabling bidirectional fault-tolerant communication via dedicated SPI channels. Its single high-side switch integrates voltage, current, and temperature sensing with real-time protection logic including overcurrent, overtemperature, and undervoltage lockout.

Diagnostic reporting occurs exclusively through SPI registers-eight distinct fault types (e.g., open-circuit, communication error, over-temperature) are accessible via MOSI/MISO/SCLK/NSS, with no exposed indicator pins. The device lacks parallel input support and does not provide LEDn, FLT, VDD2_WRN, or OPEN_CH outputs per ordering guide Table 1.

Key Specifications

Pinout & Package

SI83405BDA-IFR is housed in a compact 9 mm × 9 mm DFN-32 package with exposed thermal pad (EP), optimized for high-density industrial PCB layouts and thermal dissipation in confined spaces.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar isolated high-side switch applications.

Compared with SI83405BFA-IFR and SI83401BAA-IFR, SI83405BDA-IFR trades off indicator pins and parallel flexibility for pure SPI integration-reducing GPIO usage and simplifying layout at the cost of requiring full SPI firmware implementation and no hardware fault visibility.

Availability

SI83405BDA-IFR is available at Aetrix Electronics and suitable for programmable logic controllers, industrial motion controllers, and smart solid-state relays requiring stable component supply, long-term industrial lifecycle support, and certified isolation performance.

Supply support for SI83405BDA-IFR 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 for infrastructure, automotive, and industrial markets.

The Si834x product line was designed specifically for industrial programmable controller I/O modules, replacing optocoupler-based relay drivers with integrated isolation, protection, and digital diagnostics in a single package.

FAQ

What is the isolation architecture used in SI83405BDA-IFR?

The SI83405BDA-IFR uses Skyworks' proprietary RF-based CMOS isolation technology across a 1.5 kVRMS barrier. Unlike optocouplers, it modulates an RF carrier instead of light, eliminating LED degradation and offering >100 kV/µs CMTI. This architecture ensures stable timing, high reliability, and long-term performance consistency in harsh industrial environments-key attributes confirmed in the official Si834x datasheet revision 206512A.

Does SI83405BDA-IFR support parallel input control in addition to SPI?

No, SI83405BDA-IFR supports SPI-only interface per the ordering guide (Table 1). It lacks parallel input pins (A1–A4), OE (output enable), and status indicator outputs (LED1–LED4, VDD2_WRN, OPEN_CH). Control and diagnostics are exclusively accessed via MOSI/MISO/SCLK/NSS. This distinguishes SI83405BDA-IFR from variants like SI83405BFA-IFR, which supports dual-mode operation.

What fault conditions does SI83405BDA-IFR report, and how are they accessed?

SI83405BDA-IFR reports eight diagnostic conditions-including over-temperature, over-current, open-circuit, VDD2 undervoltage, and SPI communication error-exclusively through its SPI interface. These are stored in device status registers and read via MISO. No fault information is available on pin outputs (e.g., FLT is present but aggregates all faults without differentiation), making SPI mandatory for granular diagnostics.

What is the maximum inrush current capability of SI83405BDA-IFR, and how is it activated?

SI83405BDA-IFR delivers 8 A peak inrush current for 20 ms to support cold filament lamps and high-inductance solenoids. This mode is automatically engaged during initial turn-on when load characteristics trigger the internal inrush detection circuit-no configuration or SPI command is required. It operates independently of the 2.5 A continuous rating and prevents false overcurrent shutdown during startup transients.

Is SI83405BDA-IFR compliant with industrial safety standards?

Yes, SI83405BDA-IFR carries pending UL 1577 recognition (1500 Vrms, 1 minute), CSA certification to 62368-1, and CQC approval to GB4943.1. It also complies with IEC 61131-2 for programmable controller interfaces. These certifications validate its suitability for use in safety-critical industrial control equipment where reinforced isolation and fault containment are mandated.