SN74F251BD Equivalent & Substitute Parts

Part Overview

The SN74F251BD is a 1 x 8:1 multiplexer logic integrated circuit manufactured by Texas Instruments in a 16-SOIC surface mount package. This component is classified as Last Time Buy, indicating discontinued production with limited availability. The identification of equivalent and substitute parts is necessary to ensure design continuity and procurement flexibility for applications requiring 8-to-1 multiplexing functionality with identical electrical and mechanical specifications.

Substiute Parts

SN74F251BD

Texas InstrumentsIn Stock: 2026SN74F251BD Datasheet

Current PartRFQ

SN74F251BDR

Texas InstrumentsIn Stock: 2999SN74F251BDR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SN74F251BD is determined by strict equivalence across the following critical parameters:

• Base product number (74F251 series)
• Multiplexer circuit configuration (1 x 8:1)
• Package type (16-SOIC with 0.154" width, 3.90mm)
• Electrical specifications (4.5V ~ 5.5V supply, 3mA/24mA output current)
• Operating temperature range (0°C ~ 70°C)
• Surface mount mounting type
• Compliance certifications (ROHS3, REACH Unaffected)

The SN74F251BDR qualifies as a direct substitute based on identical adherence to all parameters listed above. The primary distinction between these parts is packaging format: tube versus tape & reel.

Parameter Comparison

Engineering Selection Recommendations

The SN74F251BDR is the direct substitute for the SN74F251BD. Both parts maintain identical electrical and mechanical specifications, including voltage supply range, output current ratings, operating temperature, and package dimensions. The SN74F251BDR carries Active product status, ensuring continued availability and supply chain stability compared to the Last Time Buy status of the SN74F251BD. Both parts satisfy ROHS3 compliance and REACH unaffected requirements. Selection between these parts should be based on packaging requirements: tube format for the SN74F251BD or tape & reel format for the SN74F251BDR.

Frequently Asked Questions (FAQ)

Q: Can the SN74F251BDR replace the SN74F251BD in existing designs?

A: Yes. Both parts are electrically and mechanically identical. The SN74F251BDR operates within the same voltage supply range (4.5V ~ 5.5V), delivers identical output current specifications (3mA, 24mA), and is housed in the same 16-SOIC package. PCB layout and schematic integration require no modification.

Q: What is the difference between tube and tape & reel packaging?

A: Tube packaging (SN74F251BD) is suitable for manual handling and small-quantity applications. Tape & reel packaging (SN74F251BDR) is designed for automated assembly processes and high-volume production. Both formats contain identical components with no electrical or functional differences.

Q: Why is the SN74F251BD marked as Last Time Buy?

A: Last Time Buy status indicates that Texas Instruments has discontinued production of this part number. The SN74F251BDR, carrying Active status, represents the current production equivalent and is recommended for new designs and long-term procurement planning.

Q: Are there any compliance or certification differences between these parts?

A: No. Both the SN74F251BD and SN74F251BDR maintain identical ROHS3 compliance, REACH unaffected status, and MSL rating of 1 (Unlimited). No additional qualification or testing is required when transitioning between these parts.

Q: What are the critical parameters for substitution compatibility?

A: Substitution compatibility is determined by: base product number (74F251), multiplexer circuit configuration (1 x 8:1), package type (16-SOIC), voltage supply range (4.5V ~ 5.5V), output current ratings (3mA, 24mA), and operating temperature range (0°C ~ 70°C). Deviation in any of these parameters disqualifies a part as a direct substitute.