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Skyworks Solutions Inc. SI8401AA-B-ISR
- Part No.:
- SI8401AA-B-ISR
- Manufacturer:
- Skyworks Solutions Inc.
- Category:
- Digital Isolators
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
SI8401AA-B-ISR.pdf
- Description:
- DGTL ISOL 1000VRMS 2CH I2C 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:1,380
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Product details
Overview
SI8401AA-B-ISR from Skyworks Solutions is a bidirectional I²C isolator with two galvanically isolated, open-drain SDA and SCL channels supporting up to 1.7 MHz clock frequency, 2500 VRMS isolation rating, and 3.0–5.5 V dual-supply operation. It implements RF-based isolation for robust noise immunity in hot-swap SMBus interfaces between isolated power domains.
For engineers reviewing the SI8401AA-B-ISR datasheet, SI8401AA-B-ISR pinout, SI8401AA-B-ISR application, or SI8401AA-B-ISR equivalent, this device delivers verified bidirectional I²C channel timing (≤29 ns propagation delay), integrated UVLO protection, and SOIC-8 narrow-body package compatibility for space-constrained industrial bus isolation.
Technical Context
The SI8401AA-B-ISR uses proprietary RF on/off keying across a semiconductor isolation barrier-eliminating startup initialization and enabling deterministic latency. Its dual-side UVLO monitors (AVDDUV+ = 2.3 V typ, BVDDUV+ = 2.3 V typ) independently manage side-A and side-B power sequencing during hot-swap events.
Each I²C channel features asymmetric drive capability: side-B outputs sink up to 35 mA (open-drain), while side-A outputs sink ≤15 mA. Logic thresholds are defined per side: side-A I²C input threshold is 650 mV typ, side-B logic low input voltage is ≤0.8 V, ensuring interoperability with standard I²C masters and slaves.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Isolation Rating | 2500 VRMS for 1 minute - certified for reinforced insulation per UL 1577, CSA 5A, and VDE 0884-2. |
| I²C Bus Frequency | Up to 1.7 MHz - supports standard-mode and fast-mode-plus I²C timing without external pull-up tuning. |
| Propagation Delay | ≤29 ns (side A→B rising, 5 V) - enables sub-100 ns round-trip latency critical for real-time sensor bus arbitration. |
| Supply Voltage Range | 3.0–5.5 V per side - allows independent biasing of isolated domains (e.g., 3.3 V MCU side / 5 V sensor side). |
| Output Sink Current | 35 mA on side-B SDA/SCL - drives standard 1 kΩ pull-ups at 5 V while maintaining VOL ≤400 mV. |
| Common-Mode Transient Immunity | 25 kV/µs - prevents data corruption during fast transients in motor-drive or PoE environments. |
| Operating Temperature | –40 °C to +125 °C - qualified for under-hood automotive and industrial control cabinet deployment. |
Pinout & Package
SI8401AA-B-ISR is housed in an 8-pin narrow-body SOIC package (SOIC-8 NB) with creepage/clearance ≥4.0 mm and 2.54 mm pitch. Pin 1 is marked with a dot; pins 1–4 connect to side-A circuitry (AGND, ASCL, ASDA, AVDD), pins 5–8 to side-B (BGND, BSCL, BSDA, BVDD).
| Pin | Circuit Role | Design Meaning |
|---|---|---|
| 1 | AGND | Side-A ground reference - must be connected to local side-A power domain ground plane. |
| 2 | ASCL | Side-A bidirectional I²C clock - open-drain, requires external pull-up; interfaces to master or slave SCL line. |
| 3 | ASDA | Side-A bidirectional I²C data - open-drain, requires external pull-up; interfaces to master or slave SDA line. |
| 4 | AVDD | Side-A supply voltage - powers side-A logic and drivers; decoupling capacitor required within 1 cm. |
| 5 | BGND | Side-B ground reference - galvanically isolated from AGND; connects to side-B domain ground. |
| 6 | BSCL | Side-B bidirectional I²C clock - electrically isolated mirror of ASCL; maintains I²C protocol integrity across barrier. |
| 7 | BSDA | Side-B bidirectional I²C data - electrically isolated mirror of ASDA; supports full-duplex read/write handshaking. |
| 8 | BVDD | Side-B supply voltage - powers side-B logic and 35 mA sink drivers; independent regulation enables mixed-voltage systems. |
Key Features
| Feature | Design Value |
|---|---|
| RF-based isolation architecture | Eliminates LED aging and temperature drift issues of optocouplers; provides stable propagation delay over –40 °C to +125 °C. |
| Hot-swap capable I²C channels | Prevents bus lockup when inserting unpowered devices into live systems via internal protection circuits and Hi-Z output behavior. |
| Independent side-A/side-B UVLO | Ensures safe reset sequencing: each side exits UVLO only after its own VDD exceeds 2.3 V, avoiding metastable states. |
| Asymmetric output drive strength | Side-B 35 mA sink capability supports legacy 5 V I²C peripherals; side-A 15 mA matches modern 3.3 V MCU outputs. |
| Low-power operation | Typical 3.2 mA / 2.9 mA (AVDD/BVDD) at 1.7 MHz - reduces thermal load in dense PCB layouts with multiple isolators. |
Applications
| Industrial Motor Control | Power over Ethernet (PoE) |
|---|---|
|
Use Scenario: Isolating I²C communication between MCU host and isolated gate driver ICs in servo amplifier modules. IC Role / Device Role / Timing Role: Bidirectional I²C isolator bridging 24 V power stage domain and 3.3 V control domain with <29 ns latency. Use Value: Prevents ground-loop-induced current spikes from corrupting configuration writes to gate driver registers during PWM switching. |
Use Scenario: Enabling I²C-based PD negotiation and status reporting between PSE controller and powered device in IEEE 802.3af/at systems. IC Role / Device Role / Timing Role: Galvanic barrier for SDA/SCL lines crossing 48 V DC power isolation boundary with 2500 VRMS rating. Use Value: Maintains SMBus packet integrity during high dv/dt events caused by PoE power-up sequencing and fault recovery. |
| Intelligent Power Systems | Hot-Swap Server Backplanes |
|
Use Scenario: Monitoring battery management ICs (e.g., fuel gauges, cell protectors) in UPS or EV charging units with floating high-side sensing. IC Role / Device Role / Timing Role: I²C isolator linking isolated analog front-end to system controller across >100 V potential difference. Use Value: Enables real-time telemetry without compromising safety certification due to 4.0 mm creepage and reinforced insulation compliance. |
Use Scenario: Supporting hot-plug detection and configuration of line cards in telecom chassis where backplane I²C buses span multiple power domains. IC Role / Device Role / Timing Role: Fault-tolerant I²C isolator that enters Hi-Z state on unpowered side to prevent bus contention during insertion. Use Value: Guarantees zero bus glitches during card insertion/removal, eliminating need for software-level bus recovery protocols. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar I²C isolation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ADUM1250ARZ | 2-channel, 1 Mbps max I²C rate; 2500 VRMS isolation; CMOS input/output (not open-drain); no side-specific UVLO. | Lacks native open-drain I²C interface - requires external level-shifting or pull-up networks for true I²C compliance. | Choose ADUM1250ARZ only if system uses buffered I²C or can accommodate added passive components. |
| ISO1540DR | 2-channel, 1 Mbps max I²C rate; 2500 VRMS isolation; integrated 10 kΩ pull-ups; side-B 20 mA sink (vs. 35 mA). | Lower side-B drive strength limits compatibility with long traces or high-capacitance I²C buses (>400 pF). | Choose ISO1540DR only for short-board, low-capacitance I²C links where 20 mA sink suffices. |
Compared with ADUM1250ARZ and ISO1540DR, SI8401AA-B-ISR provides higher I²C bandwidth (1.7 MHz vs. 1 Mbps), stronger side-B drive (35 mA), and true open-drain I²C signaling without external components-making it optimal for demanding industrial and PoE applications requiring protocol fidelity and noise resilience.
Availability
SI8401AA-B-ISR is available at Aetrix Electronics and suitable for industrial motor control, Power over Ethernet, and intelligent power systems requiring stable component supply with long-term lifecycle support.
Supply support for SI8401AA-B-ISR 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 infrastructure, automotive, and industrial markets.
The Si840x family was engineered specifically for galvanic isolation of I²C and SMBus interfaces in harsh environments-prioritizing low propagation delay, high CMTI, and seamless hot-swap operation without firmware intervention.
FAQ
What is the maximum I²C clock frequency supported by SI8401AA-B-ISR?
The SI8401AA-B-ISR supports I²C clock frequencies up to 1.7 MHz, validated across the full operating temperature range (–40 °C to +125 °C) and supply voltage range (3.0–5.5 V). This enables use in fast-mode-plus I²C applications without signal degradation or timing violations.
Does SI8401AA-B-ISR require external pull-up resistors on SDA and SCL lines?
Yes, SI8401AA-B-ISR requires external pull-up resistors on both side-A and side-B SDA and SCL lines because its I²C channels are open-drain. Typical values range from 1 kΩ to 10 kΩ depending on bus capacitance and speed; 4.7 kΩ is commonly used for 1.7 MHz operation with ≤200 pF total capacitance.
How does SI8401AA-B-ISR behave when one side loses power?
When side-A or side-B loses power (VDD drops below UVLO threshold), the corresponding side's I²C outputs enter high-impedance state to prevent bus contention. The powered side continues normal operation, and outputs resume correct logic levels within 1 µs after power restoration-enabling true hot-swap capability.
Is SI8401AA-B-ISR certified for reinforced insulation standards?
Yes, SI8401AA-B-ISR is certified for reinforced insulation per UL 1577 (2500 VRMS), CSA Component Acceptance Notice 5A (IEC 60950-1/61010-1), and VDE 0884-2 (IEC 60747-5-2), with working voltage ratings up to 560 Vpeak and creepage/clearance ≥4.0 mm in SOIC-8 narrow-body package.
What is the common-mode transient immunity (CMTI) specification for SI8401AA-B-ISR?
The SI8401AA-B-ISR has a minimum common-mode transient immunity of 25 kV/µs, measured per IEC 61000-4-4. This ensures reliable data transmission during fast transients typical in motor drives, switch-mode power supplies, and industrial fieldbus environments without bit errors or latch-up.
SI8401AA-B-ISR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Skyworks Solutions Inc.
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Not For New Designs
- Technology:
- Capacitive Coupling
- Type:
- I2C
- Isolated Power:
- No
- Number of Channels:
- 2
- Inputs - Side 1/Side 2:
- 2/2
- Channel Type:
- Bidirectional
- Voltage - Isolation:
- 1000Vrms
- Common Mode Transient Immunity (Min):
- 25kV/µs (Typ)
- Data Rate:
- -
- Propagation Delay tpLH / tpHL (Max):
- -
- Pulse Width Distortion (Max):
- -
- Rise / Fall Time (Typ):
- -
- Voltage - Supply:
- 3V ~ 5.5V
- Grade:
- -
- Qualification:
- -
- Operating Temperature:
- -40°C ~ 125°C
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SOIC
SI8401AA-B-ISR FAQ
1.How can I place an order for SI8401AA-B-ISR through Aetrix?
Please submit a Request for Quotation (RFQ) for SI8401AA-B-ISR 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 SI8401AA-B-ISR reliable?
The price and inventory of SI8401AA-B-ISR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SI8401AA-B-ISR is usually 5 days.
3.What payment methods are accepted for SI8401AA-B-ISR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SI8401AA-B-ISR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SI8401AA-B-ISR?
SI8401AA-B-ISR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SI8401AA-B-ISR 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 SI8401AA-B-ISR?
For technical support, including SI8401AA-B-ISR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SI8401AA-B-ISR requirements.
6.How does Aetrix verify that SI8401AA-B-ISR is sourced from the original manufacturer or authorized distributors?
All SI8401AA-B-ISR 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 SI8401AA-B-ISR meets industry standards.
7.What is the process for return or replacement of SI8401AA-B-ISR?
All SI8401AA-B-ISR units undergo pre-shipment inspection (PSI). If there is an issue with SI8401AA-B-ISR, 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 SI8401AA-B-ISR part is unused and in its original packaging.
Return procedure for SI8401AA-B-ISR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SI8401AA-B-ISR Tags
-
ISO1212DBQR
Texas Instruments
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ISO6721BDR
Texas Instruments
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SI8710AC-B-ISR
Skyworks Solutions Inc.
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ISO7720FDR
Texas Instruments
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ISO7721DR
Texas Instruments
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ISO7721FDR
Texas Instruments
-
SI8710CC-B-ISR
Skyworks Solutions Inc.
-
ISO6741FQDWRQ1
Texas Instruments
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ISO7721DWVR
Texas Instruments
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ISO7762FDBQR
Texas Instruments
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ISO7741DWR
Texas Instruments
-
ISO7741FDWR
Texas Instruments
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