SN74LS373NS Equivalent & Substitute Parts

Part Overview

The SN74LS373NS is a D-Type Transparent Latch integrated circuit manufactured by Texas Instruments, designed for 8:8 data latching applications with tri-state, non-inverted output configuration. This component operates within the 74LS logic family and is housed in a 20-SOIC surface mount package.

The SN74LS373NS has been discontinued at DiGi Electronics, making identification of functionally equivalent substitute parts essential for ongoing production, maintenance, and design continuity. Substitute parts must maintain identical logic functionality, electrical performance within specified tolerances, and physical compatibility with existing PCB layouts and assembly processes.

Substiute Parts

SN74LS373NS

Texas InstrumentsIn Stock: 853SN74LS373NS Datasheet

Current PartRFQ

SN74LS373NSR

Texas InstrumentsIn Stock: 5144SN74LS373NSR Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SN74LS373NS is determined by strict equivalence across the following critical parameters:

Logic Function & Configuration: The substitute part must implement identical D-Type Transparent Latch logic with 8:8 circuit configuration and tri-state output capability.

Electrical Specifications: Supply voltage range (4.75V ~ 5.25V), output current ratings (2.6mA high, 24mA low), and operating temperature range (0°C ~ 70°C) must be maintained or exceeded.

Physical Compatibility: Package type must be 20-SOIC with identical pin configuration and footprint dimensions (0.209", 5.30mm width) to ensure direct PCB compatibility without layout modification.

Regulatory Compliance: RoHS3 compliance and moisture sensitivity level must be equivalent or superior to the original specification.

The SN74LS373NSR qualifies as a direct substitute based on these criteria, with the additional benefit of active product status and improved propagation delay performance.

Parameter Comparison

Engineering Selection Recommendations

SN74LS373NSR is the qualified substitute for SN74LS373NS based on the following engineering criteria:

Product Status: The SN74LS373NSR maintains active product status with Texas Instruments, ensuring continued availability, technical support, and supply chain reliability. The original SN74LS373NS is discontinued, creating supply risk for new production and field replacements.

Regulatory Compliance: Both parts maintain ROHS3 compliance and identical moisture sensitivity level (MSL 1 - Unlimited), ensuring equivalent environmental and handling requirements.

Electrical Performance: The SN74LS373NSR delivers superior propagation delay performance (12ns versus 20ns), which represents a performance improvement without introducing timing incompatibilities in systems designed for the original 20ns specification.

Physical & Functional Equivalence: Identical package footprint (20-SOIC), pin configuration, supply voltage range, output current ratings, and operating temperature range enable direct substitution without PCB redesign or system reconfiguration.

Packaging Format: The SN74LS373NSR is supplied in Tape & Reel (TR) format, suitable for automated assembly processes. Original packaging format of SN74LS373NS is not specified in available data.

Frequently Asked Questions (FAQ)

Q: Can SN74LS373NSR be used as a direct replacement for SN74LS373NS in existing designs?

A: Yes. The SN74LS373NSR is a direct substitute with identical logic function, electrical specifications, and 20-SOIC package footprint. No PCB layout modifications or design changes are required.

Q: What is the difference in propagation delay between these parts?

A: The SN74LS373NS specifies 20ns propagation delay, while the SN74LS373NSR specifies 12ns. The substitute part is faster. Systems designed for 20ns operation will function correctly with the faster 12ns part.

Q: Are both parts RoHS compliant?

A: Yes. Both SN74LS373NS and SN74LS373NSR are ROHS3 compliant with identical moisture sensitivity level (MSL 1 - Unlimited).

Q: What packaging options are available for the substitute part?

A: The SN74LS373NSR is supplied in Tape & Reel (TR) format for automated assembly. This is the standard packaging for high-volume production environments.

Q: Is the pin configuration identical between these parts?

A: Yes. Both parts use the 20-SOIC package with identical pin assignments and footprint dimensions (0.209", 5.30mm width).

Q: Why is the original SN74LS373NS discontinued?

A: Product discontinuation decisions are made by manufacturers based on market demand, technology evolution, and production priorities. The SN74LS373NSR remains in active production as the current equivalent offering.

Q: Can these parts be used interchangeably in the same circuit board assembly?

A: Yes. Identical electrical specifications, package footprint, and pin configuration enable interchangeable use without circuit modification or performance degradation.