DM74LS279N Equivalent & Substitute Parts

Part Overview

The DM74LS279N is a quad S-R latch logic integrated circuit manufactured by onsemi in a 16-DIP package. This component provides four independent 1:1 S-R latch circuits with standard output configuration. The part is currently classified as obsolete, making identification of compatible substitutes essential for ongoing system support and component procurement.

Substiute Parts

DM74LS279N

onsemiIn Stock: 2031DM74LS279N Datasheet

Current PartRFQ

SN74LS279AN

Texas InstrumentsIn Stock: 5363SN74LS279AN Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the DM74LS279N is determined by the following critical parameters:

• Logic Function: S-R Latch with 4 independent circuits in 1:1 configuration
• Electrical Specifications: Supply voltage range 4.75V ~ 5.25V, output current ratings 400µA (high) and 8mA (low)
• Package Compatibility: 16-DIP (0.300", 7.62mm) through-hole mounting
• Operating Temperature Range: 0°C ~ 70°C
• Base Product Series: 74LS logic family

The SN74LS279AN from Texas Instruments satisfies all substitution criteria. Both parts share identical logic function, circuit configuration, supply voltage specifications, output current ratings, operating temperature range, and physical package dimensions. The substitute maintains full functional and mechanical compatibility with the original component.

Parameter Comparison

Engineering Selection Recommendations

The SN74LS279AN is a direct functional substitute for the DM74LS279N. Both components are electrically and mechanically equivalent across all specified parameters. The SN74LS279AN offers the advantage of active product status with current manufacturing availability, compared to the obsolete status of the original part.

The SN74LS279AN demonstrates improved propagation delay performance at 12ns versus the original 22ns specification, providing enhanced timing characteristics within the same functional class. The substitute achieves ROHS3 compliance, addressing regulatory requirements where applicable.

For applications requiring RoHS non-compliant components or specific onsemi sourcing, the DM74LS279N remains available through existing inventory channels. For new designs or systems requiring current-generation components with regulatory compliance, the SN74LS279AN is the appropriate selection.

Frequently Asked Questions (FAQ)

Q: Can the SN74LS279AN directly replace the DM74LS279N in existing circuit boards?

A: Yes. Both components share identical pin configurations, package dimensions (16-DIP), and electrical specifications including supply voltage (4.75V ~ 5.25V), output current ratings (400µA high, 8mA low), and operating temperature range (0°C ~ 70°C). No circuit modifications are required.

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

A: The SN74LS279AN has a propagation delay of 12ns compared to 22ns for the DM74LS279N. This represents improved timing performance in the substitute part while maintaining functional compatibility.

Q: Why is the DM74LS279N listed as obsolete?

A: The DM74LS279N has reached end-of-life status with onsemi. The SN74LS279AN from Texas Instruments remains in active production, making it the recommended choice for ongoing procurement and new applications.

Q: Are there RoHS compliance differences between these parts?

A: Yes. The DM74LS279N is RoHS non-compliant, while the SN74LS279AN is ROHS3 compliant. Applications subject to RoHS regulations should specify the SN74LS279AN.

Q: Do both parts use the same 16-DIP package?

A: Yes. Both the DM74LS279N and SN74LS279AN use the 16-DIP (0.300", 7.62mm) through-hole package with identical pin assignments and mechanical dimensions.

Q: What is the base product series for these components?

A: Both parts belong to the 74LS logic family, which defines the electrical characteristics and functional specifications for this quad S-R latch circuit.