SN74ALS520DWR Equivalent & Substitute Parts

Part Overview

The SN74ALS520DWR is an 8-bit magnitude comparator with identity output (A=B) manufactured by Texas Instruments. This logic IC operates in the 74ALS series and provides active-low output signaling. The device is classified as obsolete, making equivalent substitute parts necessary for ongoing production and maintenance applications. The SN74ALS520DW serves as a direct functional equivalent with identical electrical specifications and package configuration.

Substiute Parts

SN74ALS520DWR

Texas InstrumentsIn Stock: 3209SN74ALS520DWR Datasheet

Current PartRFQ

SN74ALS520DW

Texas InstrumentsIn Stock: 747SN74ALS520DW Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

The SN74ALS520DW qualifies as a direct substitute for the SN74ALS520DWR based on the following criteria:

Electrical Equivalence: Both parts maintain identical specifications across all critical parameters including 8-bit comparison function, active-low output logic, supply voltage range (4.5V ~ 5.5V), output current ratings (2.6mA high, 24mA low), and propagation delay (20ns @ 5V, 50pF).

Package Compatibility: Both devices use the 20-SOIC surface-mount package with identical physical dimensions (0.295", 7.50mm width), ensuring direct PCB compatibility without layout modifications.

Compliance Alignment: Both parts maintain ROHS3 compliance, MSL Level 1 rating, and identical REACH and ECCN classifications, satisfying regulatory requirements for equivalent substitution.

Key Differentiator: The primary distinction is product status—the SN74ALS520DWR is obsolete while the SN74ALS520DW is active, making the latter the recommended selection for new designs and ongoing procurement.

Parameter Comparison

Engineering Selection Recommendations

The SN74ALS520DW is the appropriate selection for applications currently using or requiring the SN74ALS520DWR. The obsolete status of the SN74ALS520DWR necessitates transition to an active product line. The SN74ALS520DW maintains full electrical and mechanical compatibility while offering the advantage of active product support and continued availability from Texas Instruments.

Both parts satisfy ROHS3 compliance requirements and carry identical regulatory classifications (REACH Unaffected, ECCN EAR99), eliminating compliance concerns during substitution. The MSL Level 1 rating on both devices indicates unlimited shelf life under standard storage conditions.

For existing designs using the SN74ALS520DWR, direct replacement with the SN74ALS520DW requires no circuit modifications, PCB layout changes, or firmware adjustments due to complete parameter alignment.

Frequently Asked Questions (FAQ)

Q: Can the SN74ALS520DW directly replace the SN74ALS520DWR without circuit modifications?

A: Yes. Both parts are electrically and mechanically identical across all specified parameters. The 20-SOIC package footprint is identical, and all electrical characteristics including voltage supply, output current, and propagation delay match exactly.

Q: What is the primary reason for substitution?

A: The SN74ALS520DWR is classified as obsolete. The SN74ALS520DW is the active equivalent from Texas Instruments, ensuring continued availability and manufacturer support.

Q: Are there any compliance differences between the two parts?

A: No. Both parts maintain ROHS3 compliance, MSL Level 1 rating, and identical REACH and ECCN classifications. Substitution does not introduce compliance risks.

Q: Does packaging differ between these parts?

A: Both use the 20-SOIC surface-mount package with identical physical dimensions (0.295", 7.50mm width). The SN74ALS520DWR ships in standard packaging while the SN74ALS520DW is supplied in tube packaging, but the component itself is identical.

Q: What are the critical parameters that define substitution eligibility?

A: The 8-bit comparison function, active-low output logic, 4.5V ~ 5.5V supply range, 20ns propagation delay, and 20-SOIC package configuration are the defining parameters. Both parts match across all these criteria.