SN74AC74D Equivalent & Substitute Parts

Part Overview

The SN74AC74D is a dual D-type flip-flop logic integrated circuit manufactured by Texas Instruments in a 14-SOIC surface mount package. This component provides two independent D-type flip-flops with Set (Preset) and Reset functions, complementary outputs, and positive edge triggering. The SN74AC74D is currently discontinued at DiGi Electronics, making equivalent substitute parts necessary for ongoing production and maintenance applications. Substitute parts must maintain identical functional specifications, electrical performance, and package compatibility to ensure direct replacement capability.

Substiute Parts

SN74AC74D

Texas InstrumentsIn Stock: 1999SN74AC74D Datasheet

Current PartRFQ

SN74AC74DR

Texas InstrumentsIn Stock: 5241SN74AC74DR Datasheet

DirectRFQ

MC74AC74DR2G

onsemiIn Stock: 2964MC74AC74DR2G Datasheet

DirectRFQ

MC74AC74DG

onsemiIn Stock: 2540MC74AC74DG Datasheet

MFR RecommendedRFQ

NLV74AC74DR2G

onsemiIn Stock: 3631NLV74AC74DR2G Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SN74AC74D is determined by strict equivalence across the following critical parameters:

• Functional Type: D-Type flip-flop with dual elements and complementary outputs
• Trigger Mechanism: Positive edge triggering
• Package Format: 14-SOIC surface mount package with identical pin configuration
• Electrical Specifications: Supply voltage range (2V ~ 6V), output current capability (24mA minimum), and operating temperature range (-40°C ~ 85°C)
• Compliance Standards: RoHS3 compliance and MSL Level 1 rating

Substitute parts are grouped into three categories based on product status and performance characteristics:

1. Direct Functional Equivalent (Active Status): SN74AC74DR - Texas Instruments, identical specifications, Cut Tape & Digi-Reel packaging
2. Manufacturer Alternative (Active Status): MC74AC74DR2G and MC74AC74DG - onsemi equivalents with minor performance variations
3. Legacy Alternative (Obsolete Status): NLV74AC74DR2G - onsemi part with degraded performance characteristics

Parameter Comparison

Engineering Selection Recommendations

Primary Recommendation: SN74AC74DR

The SN74AC74DR is the optimal substitute for the discontinued SN74AC74D. Both parts are manufactured by Texas Instruments and share identical electrical specifications, including 6ns maximum propagation delay and 2 µA quiescent current. The SN74AC74DR maintains active product status with 5208 units in stock. The only difference is packaging format (Cut Tape & Digi-Reel versus Tube), which does not affect electrical performance or pin compatibility. This part is suitable for direct replacement in all applications.

Secondary Recommendation: MC74AC74DG

The MC74AC74DG, manufactured by onsemi, is an active alternative with identical functional specifications and package format (Tube). This part exhibits slightly degraded performance with 10ns maximum propagation delay and 4 µA quiescent current compared to the main part. The MC74AC74DG is suitable for applications where propagation delay tolerance permits the 4ns increase and where quiescent current increase is acceptable. RoHS3 compliance and MSL Level 1 rating are maintained.

Tertiary Recommendation: MC74AC74DR2G

The MC74AC74DR2G, also manufactured by onsemi, provides equivalent functionality with Tape & Reel packaging. Performance characteristics are identical to the MC74AC74DG variant. This part is suitable for high-volume production environments where Tape & Reel packaging is preferred.

Not Recommended: NLV74AC74DR2G

The NLV74AC74DR2G is classified as obsolete and exhibits significantly degraded performance characteristics. Quiescent current is 40 µA (20 times higher than the main part) and maximum propagation delay is 12.5ns. This part should not be selected for new designs or applications requiring performance equivalent to the SN74AC74D.

Frequently Asked Questions (FAQ)

Q: Can I use SN74AC74DR as a direct replacement for SN74AC74D?

A: Yes. The SN74AC74DR is a direct functional equivalent manufactured by Texas Instruments with identical electrical specifications, pin configuration, and 14-SOIC package format. The only difference is packaging format (Cut Tape & Digi-Reel versus Tube), which does not affect circuit performance.

Q: What are the performance differences between Texas Instruments and onsemi alternatives?

A: The onsemi MC74AC74DR2G and MC74AC74DG variants exhibit 10ns maximum propagation delay compared to 6ns for Texas Instruments parts, and 4 µA quiescent current compared to 2 µA. These differences are acceptable for most applications but should be evaluated for timing-critical circuits.

Q: Is the NLV74AC74DR2G suitable for replacement?

A: No. The NLV74AC74DR2G is obsolete and exhibits significantly degraded performance with 40 µA quiescent current and 12.5ns propagation delay. This part should not be used for new applications.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. All substitute parts listed maintain RoHS3 compliance and MSL Level 1 (Unlimited) moisture sensitivity rating, matching the original SN74AC74D specifications.

Q: Does packaging format affect electrical compatibility?

A: No. All substitute parts use the 14-SOIC (0.154", 3.90mm Width) surface mount package with identical pin configuration. Packaging format (Tube, Cut Tape & Digi-Reel, or Tape & Reel) affects only handling and supply method, not electrical performance or circuit compatibility.

Q: Which substitute part should I select for new production?

A: Select SN74AC74DR for optimal performance matching. If SN74AC74DR is unavailable, MC74AC74DG or MC74AC74DR2G are acceptable alternatives provided the 4ns propagation delay increase and 2 µA quiescent current increase are acceptable for your application requirements.