SN74LS674N Equivalent & Substitute Parts

Part Overview

The SN74LS674N is a 16-bit parallel-to-serial shift register manufactured by Texas Instruments, housed in a 24-DIP through-hole package. This component is classified as obsolete, making equivalent substitute parts necessary for new designs and production continuity. The shift register provides tri-state output capability and operates within the standard 74LS logic family voltage range of 4.75V to 5.25V.

Substiute Parts

SN74LS674N

Texas InstrumentsIn Stock: 3116SN74LS674N Datasheet

Current PartRFQ

SN74LS674DW

Texas InstrumentsIn Stock: 987SN74LS674DW Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SN74LS674N is determined by the following core electrical and mechanical parameters:

• Logic family and function: 74LS series shift register with 16-bit parallel-to-serial capability
• Output configuration: Tri-state output
• Electrical specifications: 4.75V to 5.25V supply voltage, 0°C to 70°C operating temperature range
• Pin count and signal compatibility: 24-pin configuration with identical functional pinout

The SN74LS674DW qualifies as a direct substitute based on matching all electrical parameters and maintaining functional equivalence. The primary difference is packaging format: the substitute uses surface-mount 24-SOIC technology instead of through-hole 24-DIP, requiring PCB redesign for implementation.

Parameter Comparison

Engineering Selection Recommendations

The SN74LS674DW is the manufacturer-recommended substitute for the obsolete SN74LS674N. Both components maintain identical electrical specifications and functional characteristics within the 74LS logic family. The substitute part carries active product status, ensuring continued availability and manufacturing support from Texas Instruments.

Both parts comply with ROHS3 standards and carry unaffected REACH status, meeting current environmental and regulatory requirements. The primary consideration for implementation is the transition from through-hole to surface-mount packaging, which requires PCB layout modification but does not affect electrical performance or signal integrity.

Frequently Asked Questions (FAQ)

Q: Can the SN74LS674DW directly replace the SN74LS674N without circuit modification?

A: Electrical substitution is direct. However, the SN74LS674DW uses 24-SOIC surface-mount packaging while the SN74LS674N uses 24-DIP through-hole packaging. PCB footprint redesign is required for physical implementation.

Q: Are the pin configurations identical between these parts?

A: Both parts maintain the same 24-pin functional pinout and signal assignments. The difference is physical package format only.

Q: What is the reason for the SN74LS674N obsolescence?

A: The SN74LS674N is classified as obsolete. The SN74LS674DW in surface-mount 24-SOIC packaging represents the current active product offering from Texas Instruments for this shift register function.

Q: Do both parts meet current compliance standards?

A: Both the SN74LS674N and SN74LS674DW are ROHS3 compliant and carry unaffected REACH status, meeting current environmental regulations.

Q: What are the key parameters that determine substitution eligibility?

A: Substitution is based on matching logic family (74LS), shift register function (16-bit parallel-to-serial), tri-state output configuration, supply voltage range (4.75V to 5.25V), and operating temperature range (0°C to 70°C).