SN74ALS139D Equivalent & Substitute Parts

Part Overview

The SN74ALS139D is a Decoder/Demultiplexer logic integrated circuit manufactured by Texas Instruments, featuring a 1 x 2:4 circuit configuration in a 16-SOIC surface mount package. This component is classified as Last Time Buy, indicating discontinued production with limited inventory availability. Finding equivalent substitute parts is necessary to ensure design continuity and long-term supply chain reliability for applications requiring decoder/demultiplexer functionality.

Substiute Parts

SN74ALS139D

Texas InstrumentsIn Stock: 3750SN74ALS139D Datasheet

Current PartRFQ

SN74ALS139DR

Texas InstrumentsIn Stock: 1636SN74ALS139DR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the SN74ALS139D is determined by strict equivalence across the following critical parameters:

• Circuit configuration: 1 x 2:4 decoder/demultiplexer topology
• Package type: 16-SOIC surface mount form factor
• Electrical specifications: Voltage supply range 4.5V ~ 5.5V, output current ratings 400µA (high) and 8mA (low)
• Operating temperature range: 0°C ~ 70°C
• Compliance certifications: ROHS3, MSL Level 1

The SN74ALS139DR qualifies as a direct substitute based on identical electrical characteristics, package specifications, and compliance requirements. The primary distinction is packaging format (Cut Tape versus Tube) and product status (Active versus Last Time Buy).

Parameter Comparison

Engineering Selection Recommendations

The SN74ALS139DR is the manufacturer-recommended substitute for the SN74ALS139D. Both components maintain identical electrical and mechanical specifications, ensuring direct functional equivalence in circuit applications. The SN74ALS139DR carries Active product status, providing assured long-term availability compared to the Last Time Buy designation of the SN74ALS139D. Both parts satisfy ROHS3 compliance and MSL Level 1 requirements. Selection between these parts should be based on procurement requirements: the SN74ALS139DR is preferred for new designs and ongoing production due to its active status and standard Cut Tape packaging format.

Frequently Asked Questions (FAQ)

Q: Can the SN74ALS139DR be used as a direct replacement for the SN74ALS139D in existing designs?

A: Yes. Both parts are electrically and mechanically identical, with matching voltage supply ranges, output current specifications, operating temperature ranges, and 16-SOIC package dimensions. No circuit modifications are required.

Q: What is the difference between Tube and Cut Tape packaging?

A: Tube packaging is used for lower-volume orders and manual assembly processes, while Cut Tape (CT) packaging is standard for automated pick-and-place assembly. Both formats contain identical components; the difference is in delivery and handling format only.

Q: Why is the SN74ALS139D marked as Last Time Buy?

A: Last Time Buy status indicates that Texas Instruments has discontinued production of this specific part number. The SN74ALS139DR, with identical specifications and Active status, is the recommended alternative for continued supply.

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

A: No. Both the SN74ALS139D and SN74ALS139DR maintain identical ROHS3 compliance, MSL Level 1 rating, REACH Unaffected status, and ECCN/HTSUS classifications.

Q: What inventory considerations should guide part selection?

A: The SN74ALS139D has 3700 units in stock with Last Time Buy status, representing finite inventory. The SN74ALS139DR has 1532 units available with Active product status, ensuring replenishment capability for future orders.