DM74AS257M Equivalent & Substitute Parts

Part Overview

The DM74AS257M is a 4 x 2:1 multiplexer logic integrated circuit manufactured by onsemi in a 16-SOIC surface mount package. This component is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing production requirements. The DM74AS257M performs digital multiplexing functions with single supply operation and standard TTL-compatible logic levels.

Substiute Parts

DM74AS257M

onsemiIn Stock: 2231DM74AS257M Datasheet

Current PartRFQ

SN74AS257D

Texas InstrumentsIn Stock: 899SN74AS257D Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the DM74AS257M is based on strict electrical and mechanical parameter matching within the 74AS logic family. The substitute part must satisfy the following criteria:

• Identical circuit configuration: 4 x 2:1 multiplexer topology
• Matching package type: 16-SOIC surface mount with 0.154" (3.90mm) width
• Equivalent electrical specifications: 4.5V to 5.5V single supply operation
• Identical output current ratings: 15mA high, 48mA low
• Compatible operating temperature range: 0°C to 70°C minimum
• Same logic family designation: 74AS series

The SN74AS257D from Texas Instruments meets all substitution criteria as a parametric equivalent within the 74AS multiplexer family.

Parameter Comparison

Engineering Selection Recommendations

The SN74AS257D is the direct substitute for the obsolete DM74AS257M. Both components share identical electrical specifications, package geometry, and pin configuration. The SN74AS257D maintains active product status with Texas Instruments, ensuring long-term availability and supply chain continuity.

Both parts carry equivalent regulatory compliance: REACH Unaffected status, EAR99 export classification, and unlimited moisture sensitivity level (MSL 1). The SN74AS257D is RoHS3 compliant, providing additional environmental compliance assurance for new designs.

Selection between these parts depends on supply availability and procurement requirements. The DM74AS257M is obsolete; the SN74AS257D is the recommended active alternative for all new applications and production continuity.

Frequently Asked Questions (FAQ)

Q: Can the SN74AS257D directly replace the DM74AS257M without circuit modification?

A: Yes. Both parts are pin-for-pin compatible with identical electrical characteristics, package dimensions, and operating parameters. No circuit redesign is required.

Q: Are there differences in the 16-SOIC package between manufacturers?

A: No. Both the DM74AS257M and SN74AS257D use the standard 16-SOIC package with 0.154" (3.90mm) width, ensuring mechanical and electrical compatibility on the same PCB footprint.

Q: What is the significance of the DM74AS257M being obsolete?

A: Obsolete status indicates the part is no longer manufactured by onsemi. The SN74AS257D from Texas Instruments is the active equivalent, ensuring continued availability for replacement and new production.

Q: Do both parts meet the same regulatory requirements?

A: Yes. Both the DM74AS257M and SN74AS257D are REACH Unaffected and classified as EAR99 for export purposes. The SN74AS257D additionally carries RoHS3 compliance certification.

Q: Are the output current specifications identical?

A: Yes. Both parts deliver 15mA output high current and 48mA output low current, maintaining identical drive capability for downstream logic circuits.

Q: What supply voltage range do these multiplexers support?

A: Both the DM74AS257M and SN74AS257D operate on a single 4.5V to 5.5V supply, compatible with standard TTL and CMOS logic systems within this voltage range.