SN74LS138NE4 Equivalent & Substitute Parts

Part Overview

The SN74LS138NE4 is a 3-line to 8-line decoder/demultiplexer logic integrated circuit manufactured by Texas Instruments. This device decodes three binary input lines into eight mutually exclusive output lines, functioning as a 1 x 3:8 decoder/demultiplexer. The part is housed in a 16-pin DIP package and operates from a single 5V supply. The SN74LS138NE4 maintains Active product status and is RoHS3 compliant, making it suitable for modern electronic applications. Equivalent and substitute parts are identified based on matching electrical specifications, mechanical packaging, and functional circuit topology.

Substiute Parts

SN74LS138NE4

Texas InstrumentsIn Stock: 803SN74LS138NE4 Datasheet

Current PartRFQ

SN74LS138N

Texas InstrumentsIn Stock: 16267SN74LS138N Datasheet

Parametric EquivalentRFQ

SN74S138AN

Texas InstrumentsIn Stock: 2048SN74S138AN Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SN74LS138NE4 are identified through strict parametric equivalence. The critical parameters determining substitutability are:

Functional Parameters:

• Circuit configuration: 1 x 3:8 decoder/demultiplexer topology
• Independent circuits: 1
• Type: Decoder/Demultiplexer

Electrical Parameters:

• Voltage supply range: 4.75V ~ 5.25V
• Current output specifications: 400µA (high), 8mA (low)
• Operating temperature range: 0°C ~ 70°C
• Supply source: Single supply

Mechanical Parameters:

• Package type: 16-DIP (0.300", 7.62mm)
• Mounting type: Through Hole
• Supplier device package: 16-PDIP

Compliance Parameters:

• RoHS3 Compliant
• REACH Unaffected
• ECCN: EAR99

Parts matching all these parameters are classified as parametric equivalents and direct substitutes. The SN74LS138N and SN74S138AN meet these criteria.

Parameter Comparison

Engineering Selection Recommendations

SN74LS138N is a direct parametric equivalent to the SN74LS138NE4. Both parts share identical series designation (74LS), electrical specifications, and mechanical packaging. The SN74LS138N is suitable for direct substitution in applications where the SN74LS138NE4 is specified. Both parts maintain Active product status and RoHS3 compliance.

SN74S138AN is a parametric equivalent with series designation 74S instead of 74LS. The 74S series represents a different logic family within the TTL logic hierarchy. While the SN74S138AN maintains identical electrical output specifications, voltage supply range, operating temperature, and mechanical packaging, the series difference reflects variations in internal circuit design and performance characteristics. The SN74S138AN is suitable for substitution where the functional requirements and electrical interface specifications are met, and where the 74S series characteristics are acceptable for the application.

All three parts are Active products with RoHS3 compliance and REACH unaffected status, ensuring regulatory compliance for current manufacturing and deployment.

Frequently Asked Questions (FAQ)

Q: Can the SN74LS138N be used as a direct replacement for the SN74LS138NE4?

A: Yes. The SN74LS138N is a parametric equivalent with identical series designation, electrical specifications, voltage supply range, operating temperature, output current characteristics, and 16-DIP package configuration. Direct substitution is supported.

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

A: The 74LS and 74S designations indicate different TTL logic families. 74LS represents Low-Power Schottky TTL, while 74S represents Schottky TTL. Both families maintain the same functional decoder/demultiplexer operation and identical electrical interface specifications for this part. The series difference reflects internal circuit topology variations.

Q: Are all three parts pin-compatible?

A: Yes. The SN74LS138NE4, SN74LS138N, and SN74S138AN all use the 16-DIP (0.300", 7.62mm) package with identical through-hole mounting configuration. Pin compatibility is confirmed.

Q: Do all substitute parts meet the same compliance requirements?

A: Yes. All three parts are RoHS3 compliant, REACH unaffected, and classified under ECCN EAR99. Regulatory compliance is equivalent across all parts.

Q: What inventory levels are available for each part?

A: SN74LS138NE4 has 706 pieces in stock. SN74LS138N has 16,185 pieces in stock. SN74S138AN has 2,000 pieces in stock.

Q: Can the SN74S138AN be substituted for the SN74LS138NE4 in all applications?

A: The SN74S138AN meets all parametric electrical and mechanical requirements for substitution. However, the 74S series represents a different logic family. Substitution is valid where the functional decoder/demultiplexer operation and electrical interface specifications are the primary selection criteria. Application-specific performance characteristics should be evaluated based on circuit design requirements.