SI8442BB-C-ISR Digital Isolator Equivalent & Substitute Parts

Part Overview

The SI8442BB-C-ISR is a general purpose digital isolator manufactured by Skyworks Solutions Inc., featuring 4-channel capacitive coupling isolation with 2500Vrms isolation voltage and 150Mbps data rate capability. This device is classified as "Not For New Designs," indicating it has been superseded in the product lifecycle. Finding equivalent and substitute parts is necessary for applications requiring continued support, inventory replenishment, or design flexibility when the primary part becomes unavailable.

Substiute Parts

SI8442BB-C-ISR

Skyworks Solutions Inc.In Stock: 1000SI8442BB-C-ISR Datasheet

Current PartRFQ

SI8642BB-B-ISR

Skyworks Solutions Inc.In Stock: 2789SI8642BB-B-ISR Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SI8442BB-C-ISR is determined by strict alignment of the following critical parameters:

• Isolation Technology: Capacitive coupling architecture
• Channel Configuration: 4-channel, 2/2 input distribution, unidirectional operation
• Isolation Voltage: 2500Vrms minimum
• Data Rate: 150Mbps minimum
• Package: 16-SOIC (0.295", 7.50mm Width) surface mount
• Supply Voltage Range: Compatibility with 2.7V ~ 5.5V operation
• Operating Temperature: -40°C ~ 125°C range
• Compliance: ROHS3 compliance and MSL 2A rating

The SI8642BB-B-ISR qualifies as a direct substitute based on matching all critical parameters while offering improved performance characteristics in CMTI and supply voltage flexibility.

Parameter Comparison

Engineering Selection Recommendations

The SI8642BB-B-ISR is the qualified substitute for SI8442BB-C-ISR applications. Selection rationale is based on the following factors:

Product Status: The SI8642BB-B-ISR carries Active product status, whereas the SI8442BB-C-ISR is designated "Not For New Designs." This distinction is critical for long-term supply chain reliability and manufacturer support.

Compliance and Certification: Both parts maintain ROHS3 compliance and identical MSL 2A (4 Weeks) ratings, ensuring equivalent handling and storage requirements.

Electrical Compatibility: The SI8642BB-B-ISR meets or exceeds all critical electrical parameters of the SI8442BB-C-ISR. The wider supply voltage range (2.5V ~ 5.5V versus 2.7V ~ 5.5V) provides additional design flexibility. The improved CMTI specification (35kV/µs versus 25kV/µs) enhances noise immunity in high-speed switching environments.

Timing Characteristics: The SI8442BB-C-ISR exhibits faster propagation delay (9.5ns versus 13ns) and lower pulse width distortion (2.5ns versus 4.5ns). Applications with strict timing requirements should account for these differences during validation.

Package and Mechanical Compatibility: Identical 16-SOIC packaging ensures direct PCB layout compatibility without redesign.

Frequently Asked Questions (FAQ)

Q: Can SI8642BB-B-ISR be used as a direct drop-in replacement for SI8442BB-C-ISR?

A: Yes, the SI8642BB-B-ISR is electrically and mechanically compatible as a direct substitute. Both devices share identical channel configuration, isolation voltage, data rate, package, and operating temperature range. The SI8642BB-B-ISR provides equivalent or superior performance across all specified parameters.

Q: What are the key differences between these two parts?

A: The primary differences are product status (Active versus Not For New Designs), CMTI specification (35kV/µs versus 25kV/µs), supply voltage range (2.5V ~ 5.5V versus 2.7V ~ 5.5V), and timing characteristics. The SI8442BB-C-ISR offers faster propagation delay and lower pulse width distortion, while the SI8642BB-B-ISR provides improved common mode transient immunity and wider supply voltage compatibility.

Q: Are there any design considerations when switching from SI8442BB-C-ISR to SI8642BB-B-ISR?

A: The timing differences should be evaluated in applications with critical path constraints. The SI8642BB-B-ISR's longer propagation delay (13ns versus 9.5ns) and higher pulse width distortion (4.5ns versus 2.5ns) may require timing margin verification. The improved CMTI specification of the SI8642BB-B-ISR is beneficial for high-speed switching applications.

Q: Do both parts require identical PCB layout and handling procedures?

A: Yes. Both parts use the same 16-SOIC package and share identical MSL 2A (4 Weeks) moisture sensitivity ratings. PCB layout, soldering procedures, and component handling requirements are identical. No design modifications are necessary for package-related considerations.

Q: Why is SI8442BB-C-ISR marked "Not For New Designs"?

A: This designation indicates the part has been superseded in the manufacturer's product lifecycle. The SI8642BB-B-ISR represents the current active product offering with equivalent functionality and improved specifications. New designs should utilize the SI8642BB-B-ISR for long-term supply chain assurance and manufacturer support.

Q: What is the isolation voltage rating, and is it the same for both parts?

A: Both the SI8442BB-C-ISR and SI8642BB-B-ISR provide 2500Vrms isolation voltage. This rating is identical across both devices and meets the same isolation requirements.

Q: Are both parts ROHS3 compliant?

A: Yes, both the SI8442BB-C-ISR and SI8642BB-B-ISR are ROHS3 compliant. Compliance certifications are equivalent, ensuring compatibility with environmental and regulatory requirements.