SI8635BT-AS Equivalent & Substitute Parts

Part Overview

The SI8635BT-AS is an automotive-grade general purpose digital isolator manufactured by Skyworks Solutions Inc. This device provides galvanic isolation using capacitive coupling technology with 5000Vrms isolation voltage across 3 channels. The part operates at data rates up to 150Mbps with a common mode transient immunity (CMTI) of 60kV/µs and is qualified to AEC-Q100 automotive standards for operating temperatures from -40°C to 125°C.

The SI8635BT-AS is currently in active production status with 1084 pieces available in inventory. Substitute parts may be required due to supply constraints, design optimization for reduced channel requirements, or application-specific performance adjustments while maintaining core isolation and electrical specifications.

Substiute Parts

SI8635BT-AS

Skyworks Solutions Inc.In Stock: 1117SI8635BT-AS Datasheet

Current PartRFQ

SI8610BD-B-IS

Skyworks Solutions Inc.In Stock: 1335SI8610BD-B-IS Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SI8635BT-AS is evaluated based on the following critical parameters that define functional equivalence:

Isolation Voltage (5000Vrms): The substitute part must maintain the same isolation voltage rating to ensure equivalent safety margins and regulatory compliance in automotive applications.

Supply Voltage Range (2.5V ~ 5.5V): The substitute must operate within the identical supply voltage window to ensure direct compatibility with existing power distribution circuits.

Package Type (16-SOIC): Physical and electrical pin compatibility requires identical package geometry and pin count.

Operating Temperature Range (-40°C ~ 125°C): Automotive-grade thermal specifications must be maintained for consistent performance across the full operating envelope.

Technology (Capacitive Coupling): The isolation technology must remain consistent to preserve electromagnetic compatibility and signal integrity characteristics.

Data Rate (150Mbps): The substitute must support the same maximum data rate to ensure bandwidth compatibility.

The SI8610BD-B-IS is identified as a parametric equivalent substitute. While this part reduces the channel count from 3 to 1, it maintains all critical electrical parameters including isolation voltage, supply range, data rate, package type, and operating temperature range. The reduction in channel count represents a functional subset suitable for applications requiring fewer isolated channels while preserving all core isolation and performance specifications.

Parameter Comparison

Engineering Selection Recommendations

Primary Selection (SI8635BT-AS): Use the SI8635BT-AS when the application requires three isolated channels with automotive-grade qualification. This part is in active production status with established supply availability (1084 pieces in stock) and meets AEC-Q100 qualification requirements for automotive environments.

Substitute Selection (SI8610BD-B-IS): The SI8610BD-B-IS serves as a functional substitute when application requirements are limited to a single isolated channel. This part maintains identical isolation voltage (5000Vrms), supply voltage range (2.5V ~ 5.5V), data rate (150Mbps), package type (16-SOIC), and operating temperature range (-40°C ~ 125°C). Both parts employ capacitive coupling technology and are in active production status with equivalent moisture sensitivity ratings (MSL 2A).

Key Difference: The SI8610BD-B-IS exhibits a lower common mode transient immunity specification (35kV/µs versus 60kV/µs). This parameter difference must be evaluated against specific application requirements for noise immunity in high-speed switching environments.

Compliance Consideration: Both parts maintain automotive-grade specifications and identical package geometry, enabling direct PCB layout compatibility when channel count reduction is acceptable for the application.

Frequently Asked Questions (FAQ)

Q: Can the SI8610BD-B-IS directly replace the SI8635BT-AS in existing designs?

A: Direct replacement is possible only if the application requires a single isolated channel. The SI8610BD-B-IS provides identical isolation voltage, supply voltage range, data rate, and package type. However, the reduction from 3 channels to 1 channel requires circuit redesign to eliminate the unused channel signals. The lower CMTI specification (35kV/µs versus 60kV/µs) must be evaluated for the specific noise environment.

Q: Are there pin-to-pin compatibility considerations between these parts?

A: Both parts use the 16-SOIC package with identical physical dimensions (0.295" × 7.50mm width). However, pin assignments differ due to the channel count difference. Direct socket substitution is not possible without circuit modification.

Q: What is the significance of the Common Mode Transient Immunity (CMTI) difference?

A: The SI8635BT-AS specifies 60kV/µs CMTI while the SI8610BD-B-IS specifies 35kV/µs CMTI. CMTI defines the maximum rate of change of common mode voltage that the isolator can withstand without introducing errors. Applications with high-speed switching or high dV/dt environments may require the higher CMTI specification of the main part.

Q: Do both parts meet automotive qualification standards?

A: The SI8635BT-AS carries AEC-Q100 automotive qualification. The SI8610BD-B-IS does not list AEC-Q100 qualification in the provided specifications. Automotive applications requiring formal AEC-Q100 certification must use the SI8635BT-AS.

Q: What are the moisture sensitivity implications for assembly and storage?

A: Both parts carry MSL 2A (4 Weeks) rating, indicating identical moisture sensitivity levels. This requires storage in controlled humidity environments and limits the time between package opening and reflow soldering to 4 weeks under standard conditions.

Q: Are there supply voltage or thermal performance differences?

A: Both parts operate across the identical supply voltage range (2.5V ~ 5.5V) and temperature range (-40°C ~ 125°C). Propagation delay, pulse width distortion, and rise/fall time specifications are identical, indicating equivalent signal integrity performance.