SI2438-A-FT Equivalent & Substitute Parts

Part Overview

The SI2438-A-FT is a 56k modem interface IC manufactured by Skyworks Solutions Inc., designed for fax system applications using the V.34 data format. This component is classified as not for new designs, indicating it has reached end-of-life status. Finding equivalent substitute parts is necessary for maintenance, repair, and legacy system support where continued supply of the original part is limited or unavailable.

Substiute Parts

SI2438-A-FT

Skyworks Solutions Inc.In Stock: 768SI2438-A-FT Datasheet

Current PartRFQ

SI2438-B-FT

Skyworks Solutions Inc.In Stock: 1241SI2438-B-FT Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SI2438-A-FT is determined by strict alignment of the following electrical and mechanical parameters:

• Data Format: V.34 compliance
• Baud Rates: 56k operation
• Package / Case: 24-TSSOP form factor with identical 0.173" (4.40mm) width
• Mounting Type: Surface Mount configuration
• Moisture Sensitivity Level: MSL 3 (168 Hours)
• Series: ISOmodem® family designation

The SI2438-B-FT meets all these criteria and is therefore a direct substitute. Both parts share the same base product number (SI2438), package specifications, and electrical performance characteristics.

Parameter Comparison

Engineering Selection Recommendations

The SI2438-B-FT is the direct substitute for SI2438-A-FT. Selection of the substitute is based on:

• Identical electrical specifications across all critical parameters (V.34 data format, 56k baud rate)
• Matching mechanical specifications (24-TSSOP package, surface mount configuration)
• Equivalent moisture sensitivity rating (MSL 3)
• Active product status of the substitute, ensuring continued availability and supply chain support
• Compliance with the same ECCN (EAR99) and HTSUS (8542.39.0001) classifications

The SI2438-B-FT provides superior supply chain continuity due to its active status, with higher inventory availability (1174 pcs vs. 668 pcs for the original part).

Frequently Asked Questions (FAQ)

Q: Can SI2438-B-FT be used as a direct replacement for SI2438-A-FT?

A: Yes. Both parts are members of the ISOmodem® series with identical electrical performance (V.34, 56k), package specifications (24-TSSOP), and moisture sensitivity ratings (MSL 3). No design modifications are required.

Q: What is the difference between SI2438-A-FT and SI2438-B-FT?

A: The primary difference is product status. SI2438-A-FT is not for new designs, while SI2438-B-FT is active. Both parts share the same base product number and all critical electrical and mechanical parameters.

Q: Are there any package or pinout differences?

A: No. Both parts use the identical 24-TSSOP package with 0.173" (4.40mm) width. Pinout and mounting requirements are the same.

Q: What does MSL 3 (168 Hours) mean for component handling?

A: MSL 3 indicates the component can be exposed to moisture for up to 168 hours before soldering. Both parts require equivalent moisture control during storage and assembly.

Q: Why is SI2438-A-FT marked as "Not For New Designs"?

A: This designation indicates the part has reached end-of-life status. For new applications, SI2438-B-FT should be selected. For legacy system maintenance, SI2438-B-FT serves as the approved substitute.