74FST3257DTR2 Equivalent & Substitute Parts

Part Overview

The 74FST3257DTR2 is a 4 x 2:1 Multiplexer/Demultiplexer logic IC manufactured by onsemi in a 16-TSSOP surface mount package. This part is classified as obsolete, with 1365 units currently in stock. The 74FST3257DTR2 operates on single supply voltage (4V to 5.5V) and supports operating temperatures from -40°C to 85°C. Due to its obsolete status, identifying equivalent and substitute parts is essential for design continuity and long-term component availability.

Substiute Parts

74FST3257DTR2

onsemiIn Stock: 143574FST3257DTR2 Datasheet

Current PartRFQ

74FST3257DTR2G

onsemiIn Stock: 330374FST3257DTR2G Datasheet

DirectRFQ

FST3257MTCX

onsemiIn Stock: 55297FST3257MTCX Datasheet

DirectRFQ

SN74CBT3257CPWR

Texas InstrumentsIn Stock: 47791SN74CBT3257CPWR Datasheet

DirectRFQ

SN74CBT3257PW

Texas InstrumentsIn Stock: 2324SN74CBT3257PW Datasheet

DirectRFQ

SN74CBT3257PWR

Texas InstrumentsIn Stock: 2476SN74CBT3257PWR Datasheet

DirectRFQ

CBT3257APW,118

Nexperia USA Inc.In Stock: 3196CBT3257APW,118 Datasheet

SimilarRFQ

PI5C3257LE

Diodes IncorporatedIn Stock: 1443PI5C3257LE Datasheet

SimilarRFQ

PI5C3257LEX

Diodes IncorporatedIn Stock: 15451PI5C3257LEX Datasheet

SimilarRFQ

SN74CBT3257CPW

Texas InstrumentsIn Stock: 2206SN74CBT3257CPW Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 74FST3257DTR2 is determined by the following critical parameters:

Functional Equivalence: All substitute parts maintain the same 4 x 2:1 multiplexer/demultiplexer circuit configuration with identical pin counts and functionality.

Package Compatibility: All substitutes use the 16-TSSOP package with 0.173" width (4.40mm), ensuring mechanical and electrical compatibility with existing PCB layouts.

Voltage Supply Range: The main part operates at 4V to 5.5V. Substitute parts operate within overlapping or compatible voltage ranges (4.5V to 5.5V or 3V to 5.5V), maintaining functional compatibility in standard 5V logic applications.

Operating Temperature: All parts support -40°C to 85°C operating temperature range, ensuring thermal compatibility across industrial and commercial applications.

Mounting Type: All substitutes are surface mount components, maintaining assembly process compatibility.

Substitutes are categorized as direct equivalents (same base product number with different packaging) or similar alternatives (different manufacturers with identical functional specifications).

Parameter Comparison

Engineering Selection Recommendations

Direct Equivalents (onsemi 74FST Series): The 74FST3257DTR2G is the direct equivalent with improved RoHS3 compliance and higher inventory availability (3196 units). The FST3257MTCX offers the highest inventory level (55200 units) with extended voltage range (3V to 5.5V) and RoHS3 compliance, suitable for applications requiring lower voltage operation.

Active Status Alternatives (Recommended for New Designs): The SN74CBT3257CPWR (Texas Instruments) and CBT3257APW,118 (Nexperia) maintain active product status, ensuring long-term availability and manufacturer support. Both operate at 4.5V to 5.5V and are RoHS3 compliant. The SN74CBT3257CPWR has the highest inventory (47740 units) among active parts.

Last Time Buy Alternatives: The SN74CBT3257PW, SN74CBT3257PWR, PI5C3257LE, and PI5C3257LEX are classified as Last Time Buy, indicating limited future availability. These parts are suitable for existing designs requiring component replacement but not recommended for new production designs.

Voltage Consideration: The PI5C3257LE and PI5C3257LEX operate within a narrower voltage range (4.75V to 5.25V), requiring verification of circuit voltage tolerance before selection.

Frequently Asked Questions (FAQ)

Q: Can I directly replace 74FST3257DTR2 with 74FST3257DTR2G? A: Yes. Both parts share identical functional specifications, package, and pin configuration. The primary difference is packaging format (Tube vs. Tape & Reel) and RoHS compliance status. PCB layout and circuit operation remain unchanged.

Q: What is the difference between onsemi FST and Texas Instruments CBT series? A: Both series implement identical 4 x 2:1 multiplexer/demultiplexer functionality in the same 16-TSSOP package. The primary difference is the voltage supply range: FST series supports 4V to 5.5V, while CBT series supports 4.5V to 5.5V. Both operate across the same temperature range and are functionally interchangeable in standard 5V logic circuits.

Q: Is the Diodes Incorporated PI5C3257 series compatible? A: Yes, the PI5C3257LE and PI5C3257LEX are functionally equivalent. However, the narrower voltage range (4.75V to 5.25V) requires verification that your circuit operates within this specification. If your design uses 4V to 4.74V or 5.26V to 5.5V, this part is not suitable.

Q: What packaging options are available? A: Substitutes are available in three packaging formats: Tube (individual packaging), Tape & Reel (TR) for automated assembly, and Cut Tape (CT) & Digi-Reel® for semi-automated processes. Select based on your assembly method and volume requirements.

Q: Which substitute has the best long-term availability? A: The SN74CBT3257CPWR (Texas Instruments) and CBT3257APW,118 (Nexperia) maintain active product status, ensuring continued manufacturing and availability. These are recommended for new designs requiring component longevity beyond the current product lifecycle.

Q: Are all substitutes RoHS3 compliant? A: All substitute parts listed are RoHS3 compliant. The original 74FST3257DTR2 is RoHS non-compliant. If RoHS compliance is required, select from the substitute list.

Q: Can I mix different manufacturers in the same design? A: Yes. All listed substitutes maintain identical functional specifications, package dimensions, and pin configurations. Mixing manufacturers is acceptable from an electrical and mechanical standpoint. However, verify component sourcing and supply chain consistency for production builds.