DM74AS157SJ Equivalent & Substitute Parts

Part Overview

The DM74AS157SJ is a 4 x 2:1 multiplexer logic integrated circuit manufactured by onsemi in a 16-SOP surface mount package. This component is classified as obsolete, making equivalent and substitute parts necessary for ongoing production and maintenance applications. The multiplexer function allows selection of one of two input signals to route to the output based on control logic, serving as a fundamental building block in digital signal routing and data selection circuits.

Substiute Parts

DM74AS157SJ

onsemiIn Stock: 948DM74AS157SJ Datasheet

Current PartRFQ

SN74AS157NSR

Texas InstrumentsIn Stock: 2986SN74AS157NSR Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the DM74AS157SJ is determined by the following critical parameters:

• Circuit Configuration: Must be 4 x 2:1 multiplexer topology
• Package Compatibility: 16-SOIC (0.209", 5.30mm Width) surface mount package
• Voltage Supply Range: 4.5V ~ 5.5V single supply operation
• Operating Temperature Range: 0°C ~ 70°C
• Base Product Number: 74AS series logic family

The SN74AS157NSR from Texas Instruments meets all substitution criteria. Both parts share identical circuit configuration, package dimensions, voltage specifications, and temperature operating range. The 74AS logic family ensures functional and electrical compatibility across manufacturers.

Parameter Comparison

Engineering Selection Recommendations

The SN74AS157NSR qualifies as a direct substitute for the DM74AS157SJ based on functional equivalence within the 74AS logic family. Both parts maintain identical circuit topology, package form factor, and electrical operating specifications. The SN74AS157NSR carries RoHS3 compliance status, providing regulatory advantage for new designs and production environments with RoHS requirements. Both components are REACH unaffected and classified under identical ECCN and HTSUS codes, supporting consistent supply chain documentation and export compliance.

The output current specifications differ between the two parts; the SN74AS157NSR exhibits lower output current ratings (400µA high, 8mA low) compared to the DM74AS157SJ (2mA high, 20mA low). This difference must be evaluated against specific circuit load requirements to ensure adequate drive capability for downstream logic stages.

Frequently Asked Questions (FAQ)

Q: Can the SN74AS157NSR directly replace the DM74AS157SJ in existing designs?

A: Yes, the SN74AS157NSR is functionally equivalent. Both parts share the same 4 x 2:1 multiplexer configuration, 16-SOIC package dimensions, voltage supply range (4.5V ~ 5.5V), and operating temperature specifications (0°C ~ 70°C). Verify that circuit load requirements are compatible with the SN74AS157NSR output current specifications before implementation.

Q: What is the significance of the different output current ratings?

A: The DM74AS157SJ provides 2mA high and 20mA low output current, while the SN74AS157NSR provides 400µA high and 8mA low output current. These specifications define the maximum current the output can source or sink. Circuit designs must ensure that connected logic inputs do not exceed the substitute part's current capabilities.

Q: Are there package compatibility concerns?

A: No. Both the DM74AS157SJ and SN74AS157NSR use the 16-SOIC (0.209", 5.30mm Width) surface mount package. PCB footprints, solder reflow profiles, and mechanical assembly procedures remain identical.

Q: What compliance certifications apply to the substitute part?

A: The SN74AS157NSR is RoHS3 compliant and REACH unaffected. Both parts share identical ECCN (EAR99) and HTSUS (8542.39.0001) classifications, supporting consistent regulatory and export documentation.

Q: Why is the DM74AS157SJ listed as obsolete?

A: Obsolete status indicates the part is no longer manufactured or supported by onsemi. The SN74AS157NSR from Texas Instruments provides functional continuity for applications requiring 74AS157 multiplexer functionality.