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Skyworks Solutions Inc. SI8735BC-IS
- Part No.:
- SI8735BC-IS
- Manufacturer:
- Skyworks Solutions Inc.
- Category:
- Digital Isolators
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
SI8735BC-IS.pdf
- Description:
- DGTL ISO 2500VRMS 1CH GP 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:862
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Product details
Overview
SI8735BC-IS from Skyworks Solutions is a single-channel, non-inverting logic-output digital isolator with LED emulator input, rated for 15 Mbps data rate, 3.75 kVRMS isolation, and high CMTI (25 kV/µs). It replaces HCPL-0201 optocouplers in industrial motor drives and isolated power supplies where long-term reliability under thermal stress is critical.
For engineers reviewing the SI8735BC-IS datasheet, SI8735BC-IS pinout, SI8735BC-IS application, or SI8735BC-IS equivalent, this device delivers verified drop-in compatibility with optocoupler footprints, deterministic propagation delay (≤50 ns), UVLO-protected operation across –40 to +125 °C, and RoHS-compliant SOIC-8 packaging - all without optical degradation mechanisms.
Technical Context
The SI8735BC-IS implements a CMOS-based RF-modulated isolation barrier that emulates an LED input while delivering logic-level output. Its input stage accepts 0.68 mA threshold current with 0.18 mA hysteresis, and its output stage drives 4 mA loads with VOL ≤ 0.4 V and VOH ≥ VDD – 0.4 V at 5 V supply.
It features under-voltage lockout (UVLO+) at 2.2–2.35 V, startup time ≤40 µs, and operates with 2.5–5.5 V logic supply. Unlike optocouplers, it exhibits no forward-current or temperature-induced wear-out, achieving 10× lower FIT rate and stable performance over lifetime.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Data Rate | 15 Mbps - supports high-speed serial interfaces like SPI clock lines and gate driver PWM signals without timing margin loss. |
| Isolation Voltage | 3.75 kVRMS - certified per UL 1577, VDE0884-10, and CSA 5A for reinforced insulation in industrial mains-connected systems. |
| Propagation Delay | ≤50 ns (tPLH/tPHL) - enables precise timing control in motor phase commutation and synchronous rectifier gate timing. |
| CMTI | 25 kV/µs - rejects fast transients in noisy motor drive environments without output glitches or false triggering. |
| Supply Range | 2.5–5.5 V - interoperable with 3.3 V and 5 V logic families and compatible with isolated DC-DC converter outputs. |
| Input Threshold | 0.68 mA IF(TH) - requires minimal drive current from MCU GPIO or low-power controllers, reducing source-side power dissipation. |
| Operating Temp | –40 to +125 °C - qualified per AEC-Q100 and suitable for under-hood automotive subsystems and industrial enclosures. |
Pinout & Package
SI8735BC-IS uses an 8-pin narrow-body SOIC package (JEDEC MS-012) with 1.27 mm pitch, 5.0 × 4.0 mm body, and RoHS-compliant matte tin lead finish. Pin 1 is NC; pins 2 and 3 form the LED emulator input (ANODE/CATHODE); pins 5 and 7 are GND and VO; pin 8 is VDD; pins 1, 4, and 6 are NC and must be grounded for optimal CMTI.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1 | NC | No internal connection; tie to ground plane to minimize common-mode coupling and maximize transient immunity. |
| Pin 2 | ANODE | LED emulator anode input; signal applied here relative to CATHODE determines output state (non-inverting). |
| Pin 3 | CATHODE | LED emulator cathode reference; forms differential input pair with ANODE for noise-immune signal detection. |
| Pin 4 | NC | No internal connection; tie to ground plane to reduce parasitic capacitance across isolation barrier. |
| Pin 5 | GND | Output-side ground reference; may be biased above or below system ground, but VDD–GND ≤ 5.5 V. |
| Pin 6 | NC | No internal connection; tie to ground plane to maintain symmetry and improve CMTI performance. |
| Pin 7 | VO | Logic output; drives CMOS/TTL loads up to 4 mA sink/source with rail-to-rail swing referenced to GND. |
| Pin 8 | VDD | Output-side power supply; decouple with 0.1 µF + 1 µF capacitors placed adjacent to pin for clean switching. |
Key Features
| Feature | Design Value |
|---|---|
| Non-inverting logic output | VO = HIGH when ANODE > CATHODE by ≥0.68 mA; eliminates external inversion logic in gate driver feedback paths. |
| High CMTI (25 kV/µs) | Withstands rapid voltage transients across isolation barrier without output corruption - critical in IGBT/SiC half-bridge switching nodes. |
| UVLO with hysteresis | Enables safe power-up sequencing: output remains LOW until VDD exceeds 2.2 V and stays stable through 100 mV hysteresis band. |
| Low input current operation | IF(ON) = 1–15 mA range allows direct drive from 3.3 V MCU GPIO without external current-limiting resistors in many cases. |
| AEC-Q100 qualified | Validated for automotive-grade reliability (Grade 1: –40 to +125 °C), enabling use in EV battery management and traction inverter controls. |
Applications
| Industrial Motor Drives | Isolated Switch-Mode Power Supplies |
|---|---|
|
Use Scenario: Gate driving of IGBTs or SiC MOSFETs in three-phase inverters with isolated feedback loops. IC Role / Device Role / Timing Role: Isolates PWM signals from controller to gate driver while preserving edge integrity and minimizing propagation skew. Use Value: Enables <100 ns total timing uncertainty between channels, supporting >20 kHz switching frequencies without shoot-through risk. |
Use Scenario: Secondary-side sensing and primary-side feedback in offline AC-DC converters with >1 kV working voltage. IC Role / Device Role / Timing Role: Transmits error amplifier output across isolation barrier to regulate output voltage with minimal latency. Use Value: Delivers 15 Mbps bandwidth sufficient for fast transient response, replacing slower optocouplers without sacrificing safety certification. |
| Test & Measurement Equipment | Industrial Automation I/O Modules |
|
Use Scenario: Digital input conditioning for high-voltage analog front-ends in oscilloscopes and power analyzers. IC Role / Device Role / Timing Role: Provides galvanic isolation for trigger and status signals between measurement circuits and host processor. Use Value: Maintains signal fidelity up to 15 Mbps while rejecting >1500 V common-mode transients on input lines. |
Use Scenario: PLC digital input card isolating field sensors (e.g., proximity switches, limit switches) from backplane logic. IC Role / Device Role / Timing Role: Emulates optocoupler behavior for legacy-compatible design while eliminating aging-related parameter drift. Use Value: Guarantees >10-year operational life in continuous 24/7 factory environments without calibration drift or failure mode escalation. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar digital isolator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SI8735AC-IS | Lower CMTI (15 kV/µs vs. 25 kV/µs); same 3.75 kVRMS, 15 Mbps, SOIC-8 footprint. | Suitable for less noisy environments (e.g., low-dv/dt motor controls, non-SiC power stages). | Select when cost sensitivity outweighs need for highest transient immunity in high-frequency switching systems. |
| ADUM120N0BRZ | 2-channel, 150 Mbps, 5 kVRMS, 3.3 V only, different pinout; no LED emulator input. | Requires redesign of input circuitry (no anode/cathode interface); better for multi-channel, high-bandwidth digital buses. | Choose only if dual-channel isolation and higher speed are required and input interface can be re-engineered. |
Compared with SI8735AC-IS and ADUM120N0BRZ, the SI8735BC-IS uniquely combines optocoupler-pin-compatible LED emulator input, 25 kV/µs CMTI, and AEC-Q100 qualification - making it the only drop-in replacement for HCPL-0201 in demanding industrial and automotive gate drive applications.
Availability
SI8735BC-IS is available at Aetrix Electronics and suitable for industrial motor drives, isolated switch-mode power supplies, and test & measurement equipment requiring stable component supply, long-lifecycle support, and certified safety isolation.
Supply support for SI8735BC-IS 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 SI873x family was designed specifically to replace aging optocouplers in high-reliability industrial and automotive systems, leveraging proprietary CMOS isolation to eliminate LED wear-out and deliver predictable lifetime performance.
FAQ
What is the input interface type of the SI8735BC-IS?
The SI8735BC-IS features a diode-emulator input that accepts current-driven signals on pins 2 (ANODE) and 3 (CATHODE), mimicking the electrical behavior of an optocoupler's LED while eliminating optical degradation. This allows direct replacement of HCPL-0201 without circuit redesign. The SI8735BC-IS requires ≥0.68 mA input current to assert HIGH output, with 0.18 mA hysteresis for noise immunity.
Does the SI8735BC-IS have an enable pin?
No, the SI8735BC-IS does not include an output enable (EN) pin. It is a fixed-function, non-inverting logic-output isolator with pins 1, 4, and 6 designated as NC (no connect). The SI8736BC-IS variant provides EN functionality, but the SI8735BC-IS operates continuously when powered - making it ideal for always-on signal paths such as gate driver PWM or feedback loops where enable control is unnecessary.
What safety certifications apply to the SI8735BC-IS?
The SI8735BC-IS is certified to UL 1577 (2500 VRMS, 1 min), VDE0884-10 (reinforced insulation, 630 VPEAK), CSA Component Notice 5A, and CQC/GB4943.1. These approvals validate its 3.75 kVRMS isolation rating and suitability for industrial and automotive applications requiring reinforced insulation per IEC 61800-5-1 and ISO 26262 functional safety requirements.
Can the SI8735BC-IS operate from a 3.3 V supply?
Yes, the SI8735BC-IS supports VDD from 2.5 V to 5.5 V, including standard 3.3 V logic supplies. At 3.3 V, it delivers VOH ≥ 2.9 V and VOL ≤ 0.4 V while sinking or sourcing 4 mA - fully compatible with 3.3 V CMOS and TTL interfaces. Its UVLO threshold (2.2–2.35 V) ensures reliable startup and shutdown behavior across the full operating range.
How does the SI8735BC-IS compare to optocouplers in long-term reliability?
The SI8735BC-IS achieves dramatically higher reliability than optocouplers by eliminating LED wear-out mechanisms. Its CMOS isolation barrier shows no performance degradation with temperature, forward current, or time - resulting in a 10× lower FIT rate and guaranteed operation over 10+ years in continuous industrial use. Unlike optocouplers, the SI8735BC-IS maintains consistent propagation delay, CMTI, and threshold current across its entire service life.
SI8735BC-IS Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Skyworks Solutions Inc.
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tube
- Product Status:
- Active
- Technology:
- Capacitive Coupling
- Type:
- General Purpose
- Isolated Power:
- No
- Number of Channels:
- 1
- Inputs - Side 1/Side 2:
- 1/0
- Channel Type:
- Unidirectional
- Voltage - Isolation:
- 2500Vrms
- Common Mode Transient Immunity (Min):
- 25kV/µs (Typ)
- Data Rate:
- 15Mbps
- Propagation Delay tpLH / tpHL (Max):
- 50ns, 50ns
- Pulse Width Distortion (Max):
- 25ns
- Rise / Fall Time (Typ):
- 2.5ns, 2.5ns
- Voltage - Supply:
- 2.5V ~ 5.5V
- Grade:
- -
- Qualification:
- -
- Operating Temperature:
- -40°C ~ 125°C
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SOIC
SI8735BC-IS FAQ
1.How can I place an order for SI8735BC-IS through Aetrix?
Please submit a Request for Quotation (RFQ) for SI8735BC-IS 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 SI8735BC-IS reliable?
The price and inventory of SI8735BC-IS are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SI8735BC-IS is usually 5 days.
3.What payment methods are accepted for SI8735BC-IS?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SI8735BC-IS transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SI8735BC-IS?
SI8735BC-IS orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SI8735BC-IS 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 SI8735BC-IS?
For technical support, including SI8735BC-IS datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SI8735BC-IS requirements.
6.How does Aetrix verify that SI8735BC-IS is sourced from the original manufacturer or authorized distributors?
All SI8735BC-IS 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 SI8735BC-IS meets industry standards.
7.What is the process for return or replacement of SI8735BC-IS?
All SI8735BC-IS units undergo pre-shipment inspection (PSI). If there is an issue with SI8735BC-IS, 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 SI8735BC-IS part is unused and in its original packaging.
Return procedure for SI8735BC-IS:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SI8735BC-IS 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
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SI8710CC-B-ISR
Skyworks Solutions Inc.
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ISO6741FQDWRQ1
Texas Instruments
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ISO7721DWVR
Texas Instruments
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ISO7762FDBQR
Texas Instruments
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ISO7741DWR
Texas Instruments
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ISO7741FDWR
Texas Instruments
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