SN74AS74AD Equivalent & Substitute Parts

Part Overview

The SN74AS74AD is a dual D-type flip-flop logic integrated circuit manufactured by Texas Instruments, housed in a 14-SOIC surface mount package. This component functions as a 2-element D-type flip-flop with complementary outputs, set/preset and reset capabilities, and positive edge triggering. The SN74AS74AD is classified as Last Time Buy, indicating discontinued production. Identifying equivalent substitute parts is necessary to maintain design continuity and ensure component availability for new production runs and field replacements.

Substiute Parts

SN74AS74AD

Texas InstrumentsIn Stock: 2172SN74AS74AD Datasheet

Current PartRFQ

SN74AS74ADR

Texas InstrumentsIn Stock: 5740SN74AS74ADR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the SN74AS74AD is determined by strict equivalence across the following critical parameters:

• Functional Architecture: Dual D-type flip-flop with 2 elements, 1 bit per element, complementary outputs, set/preset and reset functions
• Electrical Performance: Clock frequency of 105 MHz, maximum propagation delay of 9 ns at 5V with 50pF load, positive edge triggering
• Electrical Characteristics: Output drive capability (2mA high, 20mA low), quiescent current of 16 mA, supply voltage range 4.5V to 5.5V
• Physical Package: 14-SOIC surface mount package with 0.154" (3.90mm) width
• Regulatory Compliance: ROHS3 compliance, REACH unaffected status, MSL Level 1

The SN74AS74ADR qualifies as a direct substitute based on identical electrical specifications, functional characteristics, and package configuration. The primary distinction is packaging format: the SN74AS74AD is supplied in Tube packaging, while the SN74AS74ADR is supplied in Tape & Reel (TR) format. Both maintain Active product status or equivalent availability.

Parameter Comparison

Engineering Selection Recommendations

The SN74AS74ADR is a direct functional and electrical equivalent to the SN74AS74AD. Both components meet ROHS3 compliance requirements and maintain REACH unaffected status, ensuring regulatory alignment for current and future production environments. The SN74AS74ADR carries Active product status, providing assured long-term availability compared to the Last Time Buy status of the SN74AS74AD. Selection of the SN74AS74ADR is appropriate for new designs and production continuity. The distinction between Tube and Tape & Reel packaging formats reflects supply chain and assembly process requirements rather than functional or electrical differences.

Frequently Asked Questions (FAQ)

Q: Can the SN74AS74ADR be used as a direct replacement for the SN74AS74AD in existing designs?

A: Yes. The SN74AS74ADR is electrically and functionally identical to the SN74AS74AD. Both components share identical pin configurations, electrical specifications, and performance characteristics. No circuit modifications are required.

Q: What is the difference between Tube and Tape & Reel packaging?

A: Tube packaging supplies components in plastic tubes for manual handling and small-quantity applications. Tape & Reel (TR) packaging supplies components on continuous tape wound on reels for automated assembly equipment. The components themselves are identical; packaging format selection depends on assembly process requirements and order quantities.

Q: Why is the SN74AS74AD marked as Last Time Buy?

A: Last Time Buy status indicates that Texas Instruments has discontinued production of this part number. The SN74AS74ADR, with Active product status, represents the current production equivalent and is the recommended choice for ongoing component procurement.

Q: Are there any electrical performance differences between these parts?

A: No. Both the SN74AS74AD and SN74AS74ADR operate at 105 MHz clock frequency, deliver 9 ns maximum propagation delay at 5V with 50pF load, and maintain identical output drive characteristics and quiescent current specifications.

Q: Do both parts meet the same regulatory and compliance standards?

A: Yes. Both components are ROHS3 compliant and REACH unaffected, with MSL Level 1 rating. They meet identical environmental and regulatory requirements for industrial and commercial applications.