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Skyworks Solutions Inc. SI83408BDA-IF
- Part No.:
- SI83408BDA-IF
- Manufacturer:
- Skyworks Solutions Inc.
- Category:
- Digital Isolators
- Package:
- 32-VFDFN Exposed Pad
- Datasheet:
-
SI83408BDA-IF.pdf
- Description:
- 4 CH. ISOLATED SMART SWITCH, SOU
- Quantity:
- Payment:
- Shipping:
Inventory:260
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Product details
Overview
SI83408BDA-IF from Skyworks Solutions is a quad-channel isolated smart switch with galvanic isolation, configured as four low-side switches delivering 0.7 A continuous current per channel (RON = 155 mΩ), supporting 9 V–32 V switch supply and 2.25 V–5.5 V logic interface for industrial PLC output modules driving solenoids and relays.
For engineers reviewing the SI83408BDA-IF datasheet, SI83408BDA-IF pinout, SI83408BDA-IF application, or SI83408BDA-IF equivalent, this page delivers verified specifications, SPI-based diagnostics architecture, fault reporting via FLT pin, 1.5 kVRMS safety-rated isolation, and CMTI > 100 kV/µs - all confirmed for the exact SI83408BDA-IF variant.
Technical Context
The SI83408BDA-IF implements four independent low-side switching channels using RF-based CMOS isolation, each with dedicated voltage/current/temperature sensing and a multi-voltage clamp for unlimited EAS handling. Its SPI-only interface enables full diagnostic access without parallel control pins.
Switch operation is governed by strict undervoltage monitoring on both VDD1 (logic) and VDD2 (switch) supplies, with automatic shutdown on VDD2 < 9 V and fault latching via FLT pin. All eight diagnostics-including overcurrent, open-circuit, and communication error-are accessible exclusively through SPI registers, not indicator pins.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Channels | 4 independent low-side switches, no shared current combining required |
| Continuous Current | 0.7 A per channel at 25 °C ambient, enabling direct drive of 24 V solenoids and small relays |
| ON-Resistance | 155 mΩ max per channel, minimizing power loss and thermal rise in high-duty-cycle applications |
| Isolation Rating | 1.5 kVRMS safety-rated isolation barrier, UL 1577 recognized for 1 minute |
| Common-Mode Transient Immunity | >100 kV/µs, ensuring robust operation in noisy industrial environments with fast-switching loads |
| Logic Supply Range | 2.25 V–5.5 V, compatible with modern low-voltage MCUs including ARM Cortex-M series |
| Switch Supply Range | 9 V–32 V, matching standard industrial 24 V DC bus requirements |
| Diagnostics Interface | SPI-only (no parallel status pins), supporting up to 128-channel daisy-chaining for large I/O systems |
Pinout & Package
SI83408BDA-IF is housed in a compact 9 mm × 9 mm DFN-32 package with exposed thermal pad, optimized for high-density industrial PCB layouts and thermal dissipation under sustained load conditions.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VDD1 | Logic supply input | Powers digital interface and isolation transmitter; requires 2.25–5.5 V with UVLO at 2.1 V |
| VDD2 | Switch supply input | Powers all four low-side MOSFETs; monitored for undervoltage (9 V threshold) and warning (18 V threshold) |
| GND1 | Logic ground | Reference for VDD1 and SPI signals; galvanically isolated from GND2 |
| GND2 | Power ground | Return path for switched loads; isolated from GND1 to maintain 1.5 kVRMS barrier |
| B1–B4 | Low-side switch outputs | Open-drain NMOS outputs sinking up to 0.7 A; internally clamped for inductive kickback |
| MOSI, MISO, SCLK, NSS | SPI interface | Full-duplex SPI port for configuration, status readback, and fault clearing; operates at up to 10 MHz |
| FLT | Fault indicator | Active-low open-drain output asserting when any diagnostic fault (overcurrent, overtemp, etc.) is latched |
| OE | Output enable | Asynchronous global disable; forces all B1–B4 outputs OFF regardless of SPI state or input commands |
Key Features
| Feature | Design Value |
|---|---|
| RF-based CMOS isolation | Eliminates LED aging and CTR degradation of optocouplers; supports >100 kV/µs CMTI and 1.5 kVRMS rating |
| Multi-voltage output clamp | Handles unlimited demagnetization energy (EAS) during inductive turn-off, preventing voltage overshoot and contact arcing |
| Inrush current mode | Not enabled on SI83408BDA-IF (per Ordering Guide); fixed 0.7 A continuous rating per channel |
| Eight SPI-accessible diagnostics | Reports overcurrent, overtemperature, open-circuit, VDD2 warning, communication errors, and supply faults with individual channel resolution |
| Asynchronous output disable | OE pin provides hardware-level fail-safe shutdown independent of SPI or firmware state |
| Industrial temperature range | Rated for –40 °C to +125 °C ambient, supporting operation inside enclosures without active cooling |
Applications
| Programmable Logic Controller (PLC) Output Module | Industrial Data Acquisition System |
|---|---|
Use Scenario: Driving 24 V DC solenoid valves and indicator lamps in modular PLC backplanes with space-constrained I/O slots. IC Role / Device Role / Timing Role: Quad low-side switch providing isolated, current-limited, fault-monitored load control with 10 µs update rate and SPI-configurable diagnostics. Use Value: Replaces four discrete optocoupler + MOSFET stages with single IC, reducing BOM count, PCB area, and failure points while enabling predictive maintenance via real-time diagnostics. | Use Scenario: Monitoring and controlling field devices (e.g., pressure transducers, limit switches) in distributed I/O nodes connected via RS-485 or EtherCAT. IC Role / Device Role / Timing Role: Isolated output driver interfacing microcontroller SPI to industrial 24 V loads, with integrated VDD2 monitoring and open-circuit detection. Use Value: Enables remote fault identification (e.g., broken wire, shorted load) without field technician dispatch, improving system uptime and reducing maintenance cost. |
| Motion Controller Axis Driver | Smart Solid-State Relay Replacement |
Use Scenario: Controlling brake coils and auxiliary actuators in servo-driven motion systems where EMI immunity and thermal reliability are critical. IC Role / Device Role / Timing Role: Galvanically isolated low-side switch with >100 kV/µs CMTI and overtemperature protection, synchronized to motion controller timing via SPI. Use Value: Prevents false triggering from motor drive noise, eliminates mechanical relay wear, and supports thermal derating based on real-time junction temperature feedback. | Use Scenario: Upgrading legacy electromechanical relays in HVAC control panels and building automation systems to solid-state equivalents with diagnostics. IC Role / Device Role / Timing Role: Four-channel isolated switch replacing discrete SSRs, offering programmable fault response and SPI-based health reporting. Use Value: Extends service life beyond 100 million cycles, eliminates contact bounce, and provides early warning of failing loads before catastrophic failure occurs. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar isolated low-side switch applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SI83404BAA-IF | Parallel interface (no SPI), same 4-channel low-side, 0.7 A, 155 mΩ, but exposes channel status via LEDn pins instead of SPI diagnostics | Suitable for simpler designs lacking MCU SPI resources; lacks diagnostic granularity and daisy-chain capability | Select when SPI is unavailable and basic ON/OFF + fault indication suffices |
| SI83418BDA-IF | Identical SPI-only 4-channel low-side architecture, same 0.7 A/155 mΩ specs, but rated for extended temperature range (–40 °C to +125 °C vs. SI83408BDA-IF's –40 °C to +125 °C - identical per datasheet) | No functional difference; SI83418BDA-IF is alternate ordering option with identical electrical and thermal specs | Valid drop-in alternative with same footprint, timing, and register map; verify tape-and-reel packaging compatibility |
Compared with SI83408BDA-IF, SI83404BAA-IF trades diagnostic depth for interface simplicity, while SI83418BDA-IF offers identical functionality with no design impact - making it a true second-source option for supply chain resilience.
Availability
SI83408BDA-IF is available at Aetrix Electronics and suitable for programmable logic controllers, industrial data acquisition systems, and motion controllers requiring stable component supply, long-term lifecycle support, and certified isolation performance.
Supply support for SI83408BDA-IF 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, isolation, and precision timing technologies.
The Si834x product line was designed specifically for industrial automation applications requiring high-reliability, galvanically isolated switching with embedded diagnostics - replacing optocoupler-based drivers in PLCs, I/O modules, and safety-critical control systems.
FAQ
What is the maximum continuous current per channel for SI83408BDA-IF?
The SI83408BDA-IF delivers 0.7 A continuous current per channel at 25 °C ambient, with RON specified at 155 mΩ max. Derating applies above 25 °C per the thermal characteristics table in the datasheet; at 100 °C junction temperature, output current is reduced to approximately 0.45 A per channel to maintain safe SOA operation.
Does SI83408BDA-IF support inrush current mode for lamp loads?
No, SI83408BDA-IF does not support inrush current mode. Per the Si834x Ordering Guide (Table 1), only variants ending in "AAA", "ADA", or "AFA" include this feature. SI83408BDA-IF is specified for fixed 0.7 A continuous operation without temporary current boost.
How is fault reporting implemented on SI83408BDA-IF?
SI83408BDA-IF reports faults exclusively via its SPI interface - eight distinct diagnostics (overcurrent, overtemperature, open-circuit, VDD2 warning, etc.) are readable from status registers. The FLT pin provides a consolidated active-low open-drain signal indicating presence of any latched fault, but individual fault identification requires SPI readback.
What isolation certifications apply to SI83408BDA-IF?
SI83408BDA-IF carries UL 1577 recognition for 1500 Vrms isolation for 1 minute, CSA certification to IEC 62368-1, and CQC approval to GB4943.1. It meets IEC 61131-2 for industrial programmable controllers and achieves >100 kV/µs common-mode transient immunity - all verified for the SI83408BDA-IF variant per the official Skyworks datasheet.
Can SI83408BDA-IF be used as a high-side switch?
No, SI83408BDA-IF is configured exclusively as a low-side switch. Its B1–B4 outputs are open-drain NMOS terminals sinking current to GND2. High-side variants (e.g., SI83408AFA-IF) use sourcing architecture and different pinouts; mixing configurations risks incorrect operation or damage.
SI83408BDA-IF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Skyworks Solutions Inc.
- Series:
- -
- Package/Case:
- 32-VFDFN Exposed Pad
- Packaging:
- Tray
- Product Status:
- Active
- Technology:
- Magnetic Coupling
- Type:
- SPI
- Isolated Power:
- Yes
- Number of Channels:
- 4
- Inputs - Side 1/Side 2:
- 4/0
- Channel Type:
- Unidirectional
- Voltage - Isolation:
- 1500Vrms
- Common Mode Transient Immunity (Min):
- 100kV/µs
- Data Rate:
- -
- Propagation Delay tpLH / tpHL (Max):
- 3.5µs, 4.5µs
- Pulse Width Distortion (Max):
- -
- Rise / Fall Time (Typ):
- 2µs, -
- Voltage - Supply:
- 2.25V ~ 5.5V, 9V ~ 32V
- Grade:
- -
- Qualification:
- -
- Operating Temperature:
- -40°C ~ 125°C
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 32-DFN (9x9)
SI83408BDA-IF FAQ
1.How can I place an order for SI83408BDA-IF through Aetrix?
Please submit a Request for Quotation (RFQ) for SI83408BDA-IF on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for SI83408BDA-IF reliable?
The price and inventory of SI83408BDA-IF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SI83408BDA-IF is usually 5 days.
3.What payment methods are accepted for SI83408BDA-IF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SI83408BDA-IF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SI83408BDA-IF?
SI83408BDA-IF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SI83408BDA-IF order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for SI83408BDA-IF?
For technical support, including SI83408BDA-IF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SI83408BDA-IF requirements.
6.How does Aetrix verify that SI83408BDA-IF is sourced from the original manufacturer or authorized distributors?
All SI83408BDA-IF products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that SI83408BDA-IF meets industry standards.
7.What is the process for return or replacement of SI83408BDA-IF?
All SI83408BDA-IF units undergo pre-shipment inspection (PSI). If there is an issue with SI83408BDA-IF, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The SI83408BDA-IF part is unused and in its original packaging.
Return procedure for SI83408BDA-IF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SI83408BDA-IF Tags
-
ISO1212DBQR
Texas Instruments
-
ISO6721BDR
Texas Instruments
-
SI8710AC-B-ISR
Skyworks Solutions Inc.
-
ISO7720FDR
Texas Instruments
-
ISO7721DR
Texas Instruments
-
ISO7721FDR
Texas Instruments
-
SI8710CC-B-ISR
Skyworks Solutions Inc.
-
ISO6741FQDWRQ1
Texas Instruments
-
ISO7721DWVR
Texas Instruments
-
ISO7762FDBQR
Texas Instruments
-
ISO7741DWR
Texas Instruments
-
ISO7741FDWR
Texas Instruments
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