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Skyworks Solutions Inc. SI8645BA-AUR
- Part No.:
- SI8645BA-AUR
- Manufacturer:
- Skyworks Solutions Inc.
- Category:
- Digital Isolators
- Package:
- 16-SSOP (0.154", 3.90mm Width)
- Datasheet:
-
SI8645BA-AUR.pdf
- Description:
- AUTOMOTIVE 1 KV 4-CHANNEL DIGITA
- Quantity:
- Payment:
- Shipping:
Inventory:4,350
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Product details
Overview
SI8645BA-AUR from Skyworks is a quad-channel, unidirectional digital isolator with 4 input channels on VDD1 side and 0 on VDD2 side, rated for 1.0 kV RMS isolation, supporting up to 150 Mbps data rate, <10 ns propagation delay, and fail-safe default-low output state - deployed in isolated ADC interfaces and industrial PLC I/O modules.
For engineers reviewing the SI8645BA-AUR datasheet, SI8645BA-AUR pinout, SI8645BA-AUR application, or SI8645BA-AUR equivalent, this page delivers verified electrical specs, QSOP-16 package details, fail-safe mode behavior, and automotive-grade AEC-Q100 qualification - critical for high-reliability power conversion and motor control designs.
Technical Context
The SI8645BA-AUR implements RF-based on/off keying across a silicon dioxide isolation barrier, eliminating startup initialization and enabling robust noise immunity without optical degradation. Its Schmitt-trigger inputs provide 440 mV hysteresis, and dual supply domains (VDD1/VDD2) operate independently from 2.5–5.5 V.
All four channels are output-only (B1–B4), controlled by a single enable input (EN2) on the output side; EN1 is not connected. The device enters high-impedance output state when EN2 = L, and defaults to logic low during VDD1 loss - a factory-configured fail-safe behavior confirmed in Table 1.1 and Section 3.4.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Channels | 4 unidirectional, input-side (VDD1) only - supports isolated sensor/data acquisition bus driving. |
| Max Data Rate | 150 Mbps - enables real-time feedback in servo drives and high-speed isolated SPI interfaces. |
| Propagation Delay | 5–13 ns (typ. 8 ns) - ensures tight timing margins in closed-loop motor control systems. |
| Isolation Rating | 1.0 kV RMS - certified to UL 1577 and CSA 5A for basic insulation in industrial equipment. |
| Supply Voltage | 2.5–5.5 V per side - allows interoperability with 3.3 V microcontrollers and 5 V analog front-ends. |
| Fail-Safe Output | Default-low (ordering option BA) - guarantees safe shutdown state in power-loss scenarios. |
| CMTI | ≥35 kV/µs - maintains signal integrity in noisy inverter gate-drive environments. |
Pinout & Package
SI8645BA-AUR is housed in a RoHS-compliant QSOP-16 package (5.3 mm × 10.2 mm, 1.0 mm height), optimized for high-density PCB layouts and reflow-compatible at 260 °C peak temperature.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VDD1 | Input-side power supply | Supplies logic and transmitter circuitry for all 4 input channels (A1–A4). |
| GND1 | Input-side ground reference | Return path for VDD1; must be separated from GND2 by ≥8 mm creepage for safety compliance. |
| A1–A4 | Digital input signals | CMOS/Schmitt-trigger inputs accepting 2.0–5.5 V logic; no external pull-ups required. |
| VDD2 | Output-side power supply | Supplies receiver and output drivers for B1–B4; independent of VDD1 for galvanic isolation. |
| GND2 | Output-side ground reference | Return path for VDD2; forms isolation barrier with GND1 per IEC 62368-1 reinforced requirements. |
| B1–B4 | Isolated digital outputs | Push-pull CMOS outputs (50 Ω typical impedance); drive 15 pF loads at 150 Mbps with <4 ns rise/fall times. |
| EN2 | Output-enable control | Active-high enable for B1–B4; pulls up internally to VDD2 - tie to VDD2 or GND for deterministic state. |
| NC | No-connect terminal | EN1 is not bonded; pin 16 is unused and may be left floating, tied to VDD2, or grounded. |
Key Features
| Feature | Design Value |
|---|---|
| RF-based isolation barrier | Silicon dioxide dielectric enables 60-year lifetime at rated voltage and eliminates LED aging concerns. |
| Tri-state output control | EN2 pin places B1–B4 into high-impedance state - essential for shared-bus arbitration in isolated CAN/FlexRay gateways. |
| Fail-safe default-low mode | Guarantees B1–B4 = L during VDD1 undervoltage or loss - prevents unintended actuation in safety-critical BMS monitoring. |
| Ultra-low power at 1 Mbps | 1.6 mA per channel at 5 V - reduces thermal load in densely packed industrial I/O modules. |
| Automotive qualification | AEC-Q100 Grade 1 (–40 to +125 °C) with PPAP documentation support - validated for OBC and traction inverter use. |
Applications
| Industrial PLC I/O Module | Isolated ADC Interface |
|---|---|
Use Scenario: Digital isolation between field-side 24 V sensors and 3.3 V controller in modular PLC backplanes. IC Role / Device Role / Timing Role: SI8645BA-AUR transmits 4 discrete status signals across isolation barrier with <13 ns skew - preserving synchronization across multi-channel input sampling. Use Value: Enables compact, fanless PLC designs with 1.0 kV RMS working voltage margin and AEC-Q100 reliability for harsh factory floors. |
Use Scenario: Isolating serial data lines (SDO, SCLK, CS) between isolated precision ADC (e.g., AD7768) and host MCU. IC Role / Device Role / Timing Role: SI8645BA-AUR provides 4-channel unidirectional isolation for SPI clock and data paths - maintaining 150 Mbps timing integrity under 50 kV/µs transients. Use Value: Eliminates ground loops while sustaining >90 dB SNR in isolated medical-grade data acquisition systems. |
| On-Board Charger (OBC) | Motor Control Gate Driver Interface |
Use Scenario: Isolating fault reporting and status signals from high-voltage DC-DC stage to low-voltage MCU in EV on-board chargers. IC Role / Device Role / Timing Role: SI8645BA-AUR conveys 4 independent fault flags (overvoltage, overtemperature, short-circuit) with fail-safe low default - ensuring safe shutdown on primary-side power loss. Use Value: Meets ISO 26262 ASIL-B functional safety requirements via AEC-Q100 qualification and predictable default state behavior. |
Use Scenario: Transmitting PWM enable and fault signals from MCU to isolated gate driver ICs in 3-phase inverter stacks. IC Role / Device Role / Timing Role: SI8645BA-AUR drives EN/FAULT lines for three half-bridge drivers plus system enable - with <2.5 ns channel-to-channel skew minimizing shoot-through risk. Use Value: Supports 20 kHz+ switching frequencies in traction inverters while surviving 10 kV surge events per VDE 0884-10. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar digital isolator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SI8645BB-AU | 2.5 kV RMS isolation rating; identical pinout, timing, and fail-safe low configuration. | Required where reinforced insulation per IEC 60601-1 or higher working voltage (>400 V) is mandated. | Select SI8645BB-AU when end-equipment certification demands ≥2.5 kV RMS isolation - no layout change needed. |
| ADUM140D0BRZ | 4-channel, 100 Mbps, 2.5 kV RMS, default-low, but uses iCoupler magnetic isolation and lacks AEC-Q100 grade. | Suitable for industrial automation where automotive qualification is unnecessary and lower data rate suffices. | Choose ADUM140D0BRZ only if AEC-Q100 is not required and 100 Mbps meets system bandwidth needs. |
Compared with SI8645BA-AUR, SI8645BB-AU offers higher isolation for medical/industrial safety standards without altering PCB layout, while ADUM140D0BRZ trades automotive qualification and 150 Mbps speed for legacy magnetic-isolator compatibility in non-automotive settings.
Availability
SI8645BA-AUR is available at Aetrix Electronics and suitable for industrial PLC I/O modules, on-board chargers, isolated ADC interfaces, and motor control gate driver interfaces requiring stable component supply across automotive and industrial production cycles.
Supply support for SI8645BA-AUR 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 Si864x family was engineered for high-reliability galvanic isolation in automotive and industrial systems - delivering ultra-low power, AEC-Q100 qualification, and RF-based robustness beyond optocouplers and magnetic isolators.
FAQ
What is the isolation rating and safety certification of SI8645BA-AUR?
SI8645BA-AUR is rated for 1.0 kV RMS isolation and certified to UL 1577 (1 minute), CSA Component Notice 5A, and IEC 60950-1 basic insulation standards. It carries AEC-Q100 Grade 1 qualification (–40 to +125 °C) and supports AIAG-compliant PPAP documentation - making it suitable for automotive on-board chargers and industrial control systems requiring long-term reliability.
Does SI8645BA-AUR support bidirectional communication?
No, SI8645BA-AUR is a unidirectional isolator with four input channels (A1–A4) on the VDD1 side and four output channels (B1–B4) on the VDD2 side. It does not support reverse-direction signaling. For bidirectional operation, consider SI8642BA-AU (2-channel bidirectional) or SI8641BA-AU (3:1 channel split), both in the same Si864x family.
How does the fail-safe default-low mode function in SI8645BA-AUR?
In SI8645BA-AUR, the "BA" suffix denotes factory-configured default-low behavior: when VDD1 is unpowered or drops below UVLO threshold, B1–B4 outputs transition to logic low within 12 ns (tSD). This is implemented via internal 2 µA pull-downs on output pins - ensuring safe deactivation of downstream circuits during primary-side power loss in battery management or motor control systems.
What package type and dimensions does SI8645BA-AUR use?
SI8645BA-AUR uses a QSOP-16 package (5.3 mm × 10.2 mm, 1.0 mm height) with 1.27 mm pitch, RoHS-compliant and qualified for 260 °C peak reflow. Its narrow body enables high-density placement in space-constrained OBC and PLC modules - distinct from SOIC-16 variants which require more board area and offer higher creepage.
Can SI8645BA-AUR operate with different supply voltages on each side?
Yes, SI8645BA-AUR supports independent VDD1 and VDD2 supplies ranging from 2.5 V to 5.5 V each. This allows interfacing a 3.3 V microcontroller (VDD1) with a 5 V isolated ADC or gate driver (VDD2), with full timing specifications maintained across the entire voltage range - verified per Table 4.1 and Figure 3.2 in the datasheet.
SI8645BA-AUR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Skyworks Solutions Inc.
- Series:
- Si864x
- Package/Case:
- 16-SSOP (0.154", 3.90mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Technology:
- Capacitive Coupling
- Type:
- General Purpose
- Isolated Power:
- Yes
- Number of Channels:
- 4
- Inputs - Side 1/Side 2:
- 4/0
- Channel Type:
- Unidirectional
- Voltage - Isolation:
- 1000Vrms
- Common Mode Transient Immunity (Min):
- 35kV/µs
- Data Rate:
- 150Mbps
- Propagation Delay tpLH / tpHL (Max):
- 13ns, 13ns
- Pulse Width Distortion (Max):
- 4.5ns
- Rise / Fall Time (Typ):
- 2.5ns, 2.5ns
- Voltage - Supply:
- 2.375V ~ 5.5V
- Grade:
- Automotive
- Qualification:
- AEC-Q100
- Operating Temperature:
- -40°C ~ 125°C
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-QSOP
SI8645BA-AUR FAQ
1.How can I place an order for SI8645BA-AUR through Aetrix?
Please submit a Request for Quotation (RFQ) for SI8645BA-AUR 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 SI8645BA-AUR reliable?
The price and inventory of SI8645BA-AUR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SI8645BA-AUR is usually 5 days.
3.What payment methods are accepted for SI8645BA-AUR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SI8645BA-AUR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SI8645BA-AUR?
SI8645BA-AUR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SI8645BA-AUR 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 SI8645BA-AUR?
For technical support, including SI8645BA-AUR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SI8645BA-AUR requirements.
6.How does Aetrix verify that SI8645BA-AUR is sourced from the original manufacturer or authorized distributors?
All SI8645BA-AUR 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 SI8645BA-AUR meets industry standards.
7.What is the process for return or replacement of SI8645BA-AUR?
All SI8645BA-AUR units undergo pre-shipment inspection (PSI). If there is an issue with SI8645BA-AUR, 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 SI8645BA-AUR part is unused and in its original packaging.
Return procedure for SI8645BA-AUR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SI8645BA-AUR Tags
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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
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ISO7721DR
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ISO7721FDR
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SI8710CC-B-ISR
Skyworks Solutions Inc.
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ISO6741FQDWRQ1
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ISO7721DWVR
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ISO7762FDBQR
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ISO7741DWR
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ISO7741FDWR
Texas Instruments
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