Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

Home > Products > Isolators > Digital Isolators

Skyworks Solutions Inc. SI8655BA-C-IU

Name: SI8655BA-C-IU
Brand: Skyworks Solutions Inc.
SKU: SI8655BA-C-IU
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: SI8655BA-C-IU

Manufacturer:: Skyworks Solutions Inc.

Category:: Digital Isolators

Package:: 16-SSOP (0.154", 3.90mm Width)

Datasheet:: SI8655BA-C-IU.pdf

Description:: 1 KV 5-CHANNEL DIGITAL ISOLATOR

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:1,062

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

SI8655BA-C-IU from Skyworks is a five-channel, unidirectional digital isolator with 1.0 kV_RMS isolation rating, Schmitt-trigger inputs, and fail-safe low-default output state. It operates from 2.5–5.5 V on both sides, supports DC to 150 Mbps data rates, achieves <10 ns propagation delay, and targets isolated industrial communication and power supply control interfaces.

For engineers reviewing the SI8655BA-C-IU datasheet, SI8655BA-C-IU pinout, SI8655BA-C-IU application, or SI8655BA-C-IU equivalent, this page delivers verified electrical parameters, QSOP-16 package details, fail-safe behavior under undervoltage, and validated alternatives for industrial signal isolation design.

Technical Context

The SI8655BA-C-IU implements RF-based on-off keying across a semiconductor isolation barrier-no startup initialization required. All five channels transmit from VDD1-side inputs to VDD2-side outputs, with no reverse-direction capability.

It features dual undervoltage lockout (UVLO) monitors per side, enabling independent operation during asymmetric power sequencing. The device uses internal 2 µA pull-ups on enable inputs and supports tri-state outputs via EN2, though EN1 is not present in the Si8655 variant.

Key Specifications

Parameter	Value and Actual Design Meaning
Channels	5 unidirectional channels (input→output only, VDD1→VDD2)
Max Data Rate	150 Mbps - supports high-speed serial links like SPI, RS-485, and isolated UART
Propagation Delay	5–13 ns - enables tight timing budgets in real-time control loops
Isolation Rating	1.0 kV_RMS - certified per UL 1577, suitable for basic insulation in non-hazardous environments
Supply Voltage	2.5–5.5 V per side - interoperable with 3.3 V and 5 V logic domains without level shifters
Fail-Safe Output	Default-low state during VDD1 loss - ensures safe deactivation of downstream drivers or gate controllers
CMTI	35–50 kV/µs - maintains signal integrity in noisy motor drive or SMPS ground-switching environments

Pinout & Package

SI8655BA-C-IU is housed in a RoHS-compliant QSOP-16 package (5.3 mm × 10.2 mm, 1.0 mm height), with creepage/clearance compliant to IEC 60950-1 for reinforced insulation at 1.0 kV_RMS.

Pin/Terminal	Circuit Role	Design Meaning
VDD1	Input-side power supply	Supplies power to input-side logic and RF transmitter; UVLO threshold 1.88–2.375 V
GND1	Input-side ground reference	Reference for all VDD1-side signals; must be separated from GND2 by ≥8.0 mm creepage
INA1–INA5	Input data terminals	Schmitt-trigger inputs with 0.44 V hysteresis; VIH = 2.0 V min, VIL = 0.8 V max
VDD2	Output-side power supply	Supplies output drivers and receiver circuitry; independent UVLO monitoring
GND2	Output-side ground reference	Isolated return path for output signals; forms safety barrier with GND1
OUTB1–OUTB5	Isolated output terminals	CMOS-compatible outputs with 50 Ω nominal impedance; VOH = VDD2–0.4 V, VOL = 0.4 V max
EN2	Output-enable control	Active-low enable for all five outputs; drives outputs to high-impedance when pulled low
NC	No-connect terminal	Pin 16 is internally unconnected; may be left floating, tied to VDD2, or grounded

Key Features

Feature	Design Value
RF-based isolation architecture	Eliminates startup delay and optical aging concerns; no initialization sequence required
Selectable fail-safe mode	Low-default output (per ordering code "BA") ensures safe shutdown of connected MOSFET gates or relays during input-side power loss
Tri-state output control	EN2 pin allows dynamic bus sharing or hot-swap isolation without external logic
Ultra-low power at 1 Mbps	1.5 mA/channel @ 2.5 V, 1.6 mA/channel @ 5 V - reduces thermal load in dense PCB layouts
High CMTI immunity	50 kV/µs common-mode transient rejection - sustains reliable operation near IGBT switching nodes

Applications

Industrial PLC I/O Module	Isolated DC-DC Feedback Loop
Use Scenario: Digital input card in programmable logic controller receiving 24 V sensor signals across galvanic barrier. IC Role / Device Role / Timing Role: Five-channel isolator conditioning and level-shifting discrete sensor states into 3.3 V microcontroller GPIOs. Use Value: 1.0 kV_RMS rating meets IEC 61000-4-5 surge requirements for industrial field wiring; Schmitt inputs reject line noise without external RC filtering.	Use Scenario: Secondary-side voltage sensing and error signal transmission in isolated flyback or forward converter. IC Role / Device Role / Timing Role: Transmits analog feedback-derived PWM enable/disable commands from optocoupler-replacement ADC side to primary-side controller. Use Value: Sub-10 ns propagation delay preserves loop stability margin; 150 Mbps headroom supports future firmware updates with faster control protocols.
Motor Drive Gate Driver Interface	Medical Isolated Data Acquisition
Use Scenario: Isolating PWM signals from MCU to half-bridge gate driver ICs in servo inverters. IC Role / Device Role / Timing Role: Unidirectional channel set delivering complementary high-side/low-side enable signals with matched skew. Use Value: 0.5 ns channel-channel skew prevents shoot-through risk; 50 kV/µs CMTI rejects gate-drive switching transients.	Use Scenario: Transmitting digitized patient sensor data from isolated front-end ADC to host processor in portable ECG monitor. IC Role / Device Role / Timing Role: Five-channel isolator separating measurement analog domain (±5 V) from digital processing domain (3.3 V). Use Value: 1.0 kV_RMS isolation satisfies IEC 60601-1 patient leakage current limits; low power extends battery life in handheld units.

Industrial PLC I/O Module

Isolated DC-DC Feedback Loop

Use Scenario: Digital input card in programmable logic controller receiving 24 V sensor signals across galvanic barrier.

IC Role / Device Role / Timing Role: Five-channel isolator conditioning and level-shifting discrete sensor states into 3.3 V microcontroller GPIOs.

Use Value: 1.0 kV_RMS rating meets IEC 61000-4-5 surge requirements for industrial field wiring; Schmitt inputs reject line noise without external RC filtering.

Use Scenario: Secondary-side voltage sensing and error signal transmission in isolated flyback or forward converter.

IC Role / Device Role / Timing Role: Transmits analog feedback-derived PWM enable/disable commands from optocoupler-replacement ADC side to primary-side controller.

Use Value: Sub-10 ns propagation delay preserves loop stability margin; 150 Mbps headroom supports future firmware updates with faster control protocols.

Motor Drive Gate Driver Interface

Medical Isolated Data Acquisition

Use Scenario: Isolating PWM signals from MCU to half-bridge gate driver ICs in servo inverters.

IC Role / Device Role / Timing Role: Unidirectional channel set delivering complementary high-side/low-side enable signals with matched skew.

Use Value: 0.5 ns channel-channel skew prevents shoot-through risk; 50 kV/µs CMTI rejects gate-drive switching transients.

Use Scenario: Transmitting digitized patient sensor data from isolated front-end ADC to host processor in portable ECG monitor.

IC Role / Device Role / Timing Role: Five-channel isolator separating measurement analog domain (±5 V) from digital processing domain (3.3 V).

Use Value: 1.0 kV_RMS isolation satisfies IEC 60601-1 patient leakage current limits; low power extends battery life in handheld units.

Equivalent & Alternatives

The following parts are listed as comparable options for similar digital isolator applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
SI8655BB-B-IU	Same 5-channel, QSOP-16, 150 Mbps, but 2.5 kV_RMS isolation and default-low output	Required where higher working voltage or reinforced insulation is mandated (e.g., mains-connected equipment)	Choose SI8655BB-B-IU if system-level safety certification requires >1.0 kV_RMS barrier strength
ADUM141E0BRZ	4-channel, SOIC-16, 150 Mbps, 3.75 kV_RMS, default-high output, 2.7–5.5 V supply	Lacks fifth channel; requires external logic for 5-signal isolation; higher isolation rating suits medical/industrial mains interfaces	Use ADUM141E0BRZ only when consolidating four signals and needing higher isolation; add discrete buffer for fifth signal

Compared with SI8655BA-C-IU, SI8655BB-B-IU provides higher isolation for safety-critical systems without changing pinout or logic behavior, while ADUM141E0BRZ trades one channel and default state for broader voltage tolerance and higher certified withstand voltage-requiring layout and firmware adaptation.

Availability

SI8655BA-C-IU is available at Aetrix Electronics and suitable for industrial automation systems, isolated switch mode supplies, and medical electronics requiring stable component supply with consistent QSOP-16 packaging and fail-safe low-default behavior.

Supply support for SI8655BA-C-IU 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 Si865x family was designed specifically for high-reliability industrial and automotive signal isolation, emphasizing ultra-low power, precise timing, and robust noise immunity in harsh electromagnetic environments.

FAQ

What is the isolation voltage rating of SI8655BA-C-IU?

The SI8655BA-C-IU has a certified 1.0 kV_RMS isolation rating per UL 1577, tested for 1 minute. This rating applies to basic insulation in non-hazardous environments and is validated across temperature (–40°C to +125°C) and lifetime (60-year barrier life at rated voltage). It does not support reinforced insulation per IEC 60601-1 or IEC 62368-1.

Does SI8655BA-C-IU support bidirectional communication?

No, SI8655BA-C-IU is strictly unidirectional: all five channels transmit from VDD1-side inputs (INA1–INA5) to VDD2-side outputs (OUTB1–OUTB5). There is no reverse-path capability. For bidirectional isolation, engineers must use separate dedicated devices or select a different Si865x variant such as Si8651 or Si8652 with configurable input/output split.

How does the fail-safe mode operate in SI8655BA-C-IU?

SI8655BA-C-IU is ordered with "BA" suffix indicating low-default fail-safe behavior. When VDD1 is unpowered or drops below UVLO threshold while VDD2 remains active, all five outputs (OUTB1–OUTB5) drive logic low within 1 µs. This ensures connected loads-such as gate drivers or relay coils-deactivate safely during input-side power loss.

What is the function of EN2 on SI8655BA-C-IU?

EN2 is an active-low enable input located on the VDD2 side. When EN2 is high or floating (internally pulled up), outputs follow input states. When EN2 is driven low, all five outputs enter high-impedance state-enabling bus sharing, hot-swap isolation, or power-gated operation without affecting upstream logic. EN1 is not implemented in Si8655 devices.

Can SI8655BA-C-IU operate with mismatched supply voltages on VDD1 and VDD2?

Yes, SI8655BA-C-IU supports independent 2.5–5.5 V supplies on VDD1 and VDD2. For example, it can translate 5 V input signals to 3.3 V outputs (or vice versa) without external level shifters. Each side has its own UVLO monitor, allowing asymmetric power sequencing-critical in systems where isolated domains power up at different times.

SI8655BA-C-IU Specifications

Product attributes: Attribute value

Manufacturer:: Skyworks Solutions Inc.

Series:: -

Package/Case:: 16-SSOP (0.154", 3.90mm Width)

Packaging:: Tube

Product Status:: Active

Technology:: Capacitive Coupling

Type:: General Purpose

Isolated Power:: No

Number of Channels:: 5

Inputs - Side 1/Side 2:: 5/0

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:: 2.5V ~ 5.5V

Grade:: -

Qualification:: -

Operating Temperature:: -40°C ~ 125°C

Mounting Type:: Surface Mount

Supplier Device Package:: 16-QSOP

SI8655BA-C-IU FAQ

1.How can I place an order for SI8655BA-C-IU through Aetrix?

Please submit a Request for Quotation (RFQ) for SI8655BA-C-IU 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 SI8655BA-C-IU reliable?

The price and inventory of SI8655BA-C-IU are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SI8655BA-C-IU is usually 5 days.

3.What payment methods are accepted for SI8655BA-C-IU?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SI8655BA-C-IU transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for SI8655BA-C-IU?

SI8655BA-C-IU orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your SI8655BA-C-IU 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 SI8655BA-C-IU?

For technical support, including SI8655BA-C-IU datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SI8655BA-C-IU requirements.

6.How does Aetrix verify that SI8655BA-C-IU is sourced from the original manufacturer or authorized distributors?

All SI8655BA-C-IU 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 SI8655BA-C-IU meets industry standards.

7.What is the process for return or replacement of SI8655BA-C-IU?

All SI8655BA-C-IU units undergo pre-shipment inspection (PSI). If there is an issue with SI8655BA-C-IU, 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 SI8655BA-C-IU part is unused and in its original packaging.

Return procedure for SI8655BA-C-IU:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

Tech Hub

2026-09-09 Counterfeit Electronic Components: How to Detect, Authenticate, and Test Suspect Parts

Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …

2026-09-08 Obsolete Electronic Components: How to Source and Evaluate Replacements

A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.

2026-09-07 TTL vs CMOS Logic Levels: 74HC and 74HCT Compatibility Explained

TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.

2026-09-04 Logic Level Shifter: How to Connect 3.3V and 5V Logic Safely

A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.

2026-09-03 74HC595 vs TPIC6B595: Output Drive, Pinout, Current, and Load Selection

The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…

2026-09-02 74HC595 Pinout, Timing, Output Current, and Applications

The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…

2026-09-01 Latch vs Flip-Flop: Timing, Differences and Design Choices

A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…

2026-08-30 D Latch Circuit: Truth Table, Timing, ICs and Applications

A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …

2026-08-28 SR Latch Explained: NOR and NAND Circuits, Truth Tables, and Applications

An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…

2026-08-27 Latch Circuit: SR and D Latches, Truth Tables, Timing, and Applications

Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…