SN74ALS151NS Data Selector/Multiplexer Equivalent & Substitute Parts

Part Overview

The SN74ALS151NS is a Data Selector/Multiplexer integrated circuit manufactured by Texas Instruments, configured as a 1 x 8:1 multiplexer in a 16-SOIC surface mount package. This component is classified as Last Time Buy, indicating discontinued production with limited availability. The SN74ALS151NS operates from a single 4.5V to 5.5V supply and is designed for logic-level signal routing applications requiring 8-to-1 data selection functionality.

Identification of equivalent and substitute parts is necessary due to the Last Time Buy status of the SN74ALS151NS. Alternative parts with identical or compatible electrical and mechanical specifications ensure design continuity and supply chain reliability.

Substiute Parts

SN74ALS151NS

Texas InstrumentsIn Stock: 1185SN74ALS151NS Datasheet

Current PartRFQ

SN74ALS151NSR

Texas InstrumentsIn Stock: 3411SN74ALS151NSR Datasheet

MFR RecommendedRFQ

SN74ALS251NS

Texas InstrumentsIn Stock: 715SN74ALS251NS Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SN74ALS151NS are identified based on strict equivalence of the following critical parameters:

Electrical Equivalence Criteria:

• Circuit configuration: 1 x 8:1 multiplexer topology
• Output current specifications: 2.6mA (high), 24mA (low)
• Supply voltage range: 4.5V ~ 5.5V
• Operating temperature range: 0°C ~ 70°C
• Single supply operation

Mechanical Equivalence Criteria:

• Package type: 16-SOIC surface mount
• Package dimensions: 0.209" width, 5.30mm width
• Mounting compatibility: Surface mount

Compliance Criteria:

• RoHS3 compliance
• Moisture sensitivity level: 1 (Unlimited)

Substitute parts are grouped into two categories: manufacturer-recommended direct substitutes and parametric equivalents. Both categories maintain full electrical and mechanical compatibility with the original SN74ALS151NS specification.

Parameter Comparison

Engineering Selection Recommendations

SN74ALS151NSR (Manufacturer-Recommended Substitute)

The SN74ALS151NSR is the primary substitute for the SN74ALS151NS. Both parts share identical electrical specifications and package geometry. The SN74ALS151NSR differs only in packaging format (Tape & Reel versus prototype packaging) and product status (Active versus Last Time Buy). The SN74ALS151NSR maintains ROHS3 compliance and carries REACH Unaffected status with EAR99 export classification. With 3400 units in stock, the SN74ALS151NSR provides superior supply availability compared to the main part.

SN74ALS251NS (Parametric Equivalent)

The SN74ALS251NS is a parametric equivalent offering identical electrical performance and mechanical compatibility. All critical parameters—circuit configuration, output current ratings, supply voltage range, operating temperature, and package specifications—match the SN74ALS151NS exactly. The SN74ALS251NS maintains Active product status with 684 units available. This part is suitable for applications where the specific part number variant is not critical to design requirements.

Selection Basis:

• Both substitute parts are manufactured by Texas Instruments, ensuring consistency with the original design
• All three parts comply with ROHS3 environmental standards
• Electrical and mechanical parameters are identical across all three parts
• The SN74ALS151NSR is recommended as the first choice due to manufacturer recommendation and higher inventory levels
• The SN74ALS251NS serves as an alternative when SN74ALS151NSR availability is constrained

Frequently Asked Questions (FAQ)

Q: Can the SN74ALS151NSR be used as a direct replacement for the SN74ALS151NS?

A: Yes. The SN74ALS151NSR is electrically and mechanically identical to the SN74ALS151NS. Both parts operate at 4.5V to 5.5V, deliver identical output current specifications (2.6mA high, 24mA low), and are packaged in 16-SOIC surface mount configuration. The only difference is packaging format and product status.

Q: What is the difference between the SN74ALS151NSR and SN74ALS251NS?

A: Both parts are parametric equivalents with identical electrical specifications and package geometry. The primary difference is the part number designation within the 74ALS series. Both are suitable for 1 x 8:1 multiplexer applications with identical supply voltage, output current, and temperature operating ranges.

Q: Why is the SN74ALS151NS marked as Last Time Buy?

A: Last Time Buy status indicates that Texas Instruments has discontinued production of this specific part number variant. Customers are advised to transition to active alternatives such as the SN74ALS151NSR or SN74ALS251NS to ensure long-term supply chain continuity.

Q: Are there any pinout differences between these parts?

A: No pinout differences are indicated in the provided specifications. All three parts are configured as 1 x 8:1 multiplexers in 16-SOIC packages with identical electrical characteristics.

Q: What is the moisture sensitivity level for these parts?

A: All three parts carry MSL 1 (Unlimited) rating, indicating unlimited shelf life under normal storage conditions without moisture bake requirements.

Q: Are these parts RoHS compliant?

A: Yes. All three parts are ROHS3 compliant, meeting current environmental and hazardous substance restrictions.

Q: Which substitute should I select for new designs?

A: For new designs, the SN74ALS151NSR is recommended due to its Active product status and higher inventory availability. The SN74ALS251NS is an acceptable alternative if SN74ALS151NSR supply becomes constrained.