SN74LS138NG4 Equivalent & Substitute Parts

Part Overview

The SN74LS138NG4 is a decoder/demultiplexer integrated circuit manufactured by Texas Instruments, part of the 74LS logic series. This component performs 1 x 3:8 decoding/demultiplexing functions in a 16-pin DIP package. The product is discontinued at DiGi Electronics, making identification of equivalent substitute parts essential for ongoing design support and component procurement.

Substiute Parts

SN74LS138NG4

Texas InstrumentsIn Stock: 1065SN74LS138NG4 Datasheet

Current PartRFQ

SN74S138AN

Texas InstrumentsIn Stock: 2048SN74S138AN Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SN74LS138NG4 is determined by the following critical parameters:

• Circuit Configuration: Must maintain 1 x 3:8 decoder/demultiplexer function
• Package Type: Must be 16-DIP (0.300", 7.62mm) for mechanical and electrical compatibility
• Mounting Type: Must support through-hole mounting
• Voltage Supply Range: Must operate within 4.75V ~ 5.25V
• Operating Temperature Range: Must support 0°C ~ 70°C
• Output Current Specifications: Must match 400µA (high) and 8mA (low) ratings
• Electrical Characteristics: Must maintain single supply voltage source configuration

The SN74S138AN qualifies as a parametric equivalent based on identical circuit configuration, package specifications, voltage supply range, operating temperature range, and output current ratings.

Parameter Comparison

Engineering Selection Recommendations

The SN74S138AN serves as a direct parametric equivalent to the SN74LS138NG4. Both components share identical electrical specifications, package configurations, and compliance certifications. The primary distinction is product status: the SN74LS138NG4 is discontinued, while the SN74S138AN maintains active status with confirmed inventory availability (2000 pcs). Both parts maintain ROHS3 compliance and REACH unaffected status, satisfying regulatory requirements for equivalent component selection.

Frequently Asked Questions (FAQ)

Q: Can the SN74S138AN directly replace the SN74LS138NG4 in existing designs?

A: Yes. Both components share identical circuit configuration (1 x 3:8), package type (16-DIP), voltage supply range (4.75V ~ 5.25V), operating temperature range (0°C ~ 70°C), and output current specifications (400µA / 8mA). Pin-to-pin compatibility and electrical performance are equivalent.

Q: What is the difference between the 74LS and 74S series designations?

A: The series designation indicates the logic family. Both 74LS and 74S are TTL-based logic families manufactured by Texas Instruments. For this decoder/demultiplexer function, the electrical parameters and performance characteristics remain identical across both series.

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

A: No. Both the SN74LS138NG4 and SN74S138AN maintain ROHS3 compliance and REACH unaffected status. Regulatory and environmental compliance requirements are equivalent.

Q: Why is the SN74LS138NG4 listed as discontinued?

A: Product discontinuation at DiGi Electronics reflects supplier inventory decisions and market availability. The SN74S138AN remains in active production with confirmed stock, providing continuity for component procurement and design support.

Q: Are packaging options different between these parts?

A: The SN74LS138NG4 specifies no packaging detail in the provided data. The SN74S138AN is supplied in tube packaging. Both maintain the identical 16-DIP (0.300", 7.62mm) physical package type suitable for through-hole mounting.