SN74LS138N Equivalent & Substitute Parts

Part Overview

The SN74LS138N is a 1 x 3:8 decoder/demultiplexer logic integrated circuit manufactured by Texas Instruments in the 74LS series. This component is classified as active product status with 16,185 pieces currently in stock. The SN74LS138N is housed in a 16-pin DIP package suitable for through-hole mounting applications. Equivalent and substitute parts are identified when component availability is limited, supply chain disruptions occur, or inventory requirements necessitate alternative sourcing from the same functional category.

Substiute Parts

SN74LS138N

Texas InstrumentsIn Stock: 16267SN74LS138N Datasheet

Current PartRFQ

SN74S138AN

Texas InstrumentsIn Stock: 2048SN74S138AN Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SN74LS138N are identified based on strict parametric equivalence within the following criteria:

• Identical circuit configuration (1 x 3:8 decoder/demultiplexer function)
• Matching package type (16-DIP through-hole mounting)
• Identical electrical specifications (voltage supply range 4.75V ~ 5.25V, output current ratings 400µA/8mA)
• Identical operating temperature range (0°C ~ 70°C)
• Compliance with RoHS3 and REACH requirements
• Same supplier device package designation (16-PDIP)

The SN74S138AN qualifies as a parametric equivalent based on these criteria. Both parts share identical functional specifications, electrical characteristics, and physical packaging requirements, enabling direct substitution in circuit applications.

Parameter Comparison

Engineering Selection Recommendations

Both the SN74LS138N and SN74S138AN are active products from Texas Instruments with full RoHS3 compliance and REACH unaffected status. Selection between these parts is based on inventory availability and supply chain requirements rather than functional or electrical differences. The SN74LS138N maintains higher stock levels (16,185 pieces), while the SN74S138AN provides an alternative source with 2,000 pieces available. Both parts meet identical compliance certifications and regulatory requirements for industrial and commercial applications.

Frequently Asked Questions (FAQ)

Q: Can the SN74S138AN directly replace the SN74LS138N in existing circuit designs?

A: Yes. Both parts share identical circuit configurations, electrical specifications, voltage supply requirements, operating temperature ranges, and physical packaging. Direct substitution is supported without circuit modification.

Q: Are there differences in performance between the SN74LS138N and SN74S138AN?

A: No performance differences exist within the specified parameters. Both parts deliver identical output current ratings (400µA high, 8mA low) and operate within the same voltage supply range (4.75V ~ 5.25V) and temperature range (0°C ~ 70°C).

Q: What is the significance of the series designation (74LS vs. 74S)?

A: The series designation indicates the logic family classification. Both the 74LS and 74S series are TTL-based logic families. The parametric specifications provided confirm functional equivalence for this specific decoder/demultiplexer application.

Q: Are both parts suitable for new designs?

A: Yes. Both the SN74LS138N and SN74S138AN carry active product status from Texas Instruments, indicating ongoing manufacturing support and suitability for new design implementations.

Q: Do packaging and mounting considerations differ between these parts?

A: No. Both parts are supplied in 16-DIP (0.300", 7.62mm) packages with through-hole mounting configuration, enabling identical PCB layout and assembly processes.

Q: Are there compliance or regulatory differences?

A: No. Both parts are ROHS3 compliant and REACH unaffected, meeting identical environmental and regulatory requirements for industrial applications.