SN74HC74DB Equivalent & Substitute Parts

Part Overview

The SN74HC74DB is a dual D-type flip-flop logic integrated circuit manufactured by Texas Instruments, housed in a 14-SSOP surface mount package. This device functions as a 2-element D-type flip-flop with complementary outputs, positive edge triggering, and set/reset control capabilities. The SN74HC74DB is classified as obsolete product status, making identification of active equivalent parts essential for ongoing design support, procurement continuity, and production sustainability.

Substiute Parts

SN74HC74DB

Texas InstrumentsIn Stock: 1103SN74HC74DB Datasheet

Current PartRFQ

SN74HC74DBR

Texas InstrumentsIn Stock: 5307SN74HC74DBR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SN74HC74DB is determined by strict equivalence across the following critical parameters:

Functional Parameters: The substitute part must maintain identical D-type flip-flop architecture with 2 elements, 1 bit per element, complementary outputs, positive edge triggering, and set/reset functionality.

Electrical Parameters: Clock frequency (60 MHz), propagation delay (30 ns @ 6V, 50pF), supply voltage range (2V to 6V), output current capability (5.2 mA), quiescent current (4 µA), and input capacitance (3 pF) must remain unchanged.

Physical Parameters: The substitute must use identical 14-SSOP surface mount packaging with 0.209" width (5.30mm).

Compliance Parameters: RoHS3 compliance and MSL Level 1 rating must be maintained.

The SN74HC74DBR qualifies as a direct substitute based on complete parameter equivalence across all functional, electrical, physical, and compliance specifications.

Parameter Comparison

Engineering Selection Recommendations

The SN74HC74DBR is the direct equivalent substitute for the obsolete SN74HC74DB. Both parts share identical electrical specifications, functional architecture, and physical packaging. The primary distinction is product status: the SN74HC74DB is obsolete while the SN74HC74DBR maintains active status with Texas Instruments.

Selection of the SN74HC74DBR provides the following advantages:

Compliance Continuity: Both parts maintain ROHS3 compliance and MSL Level 1 rating, ensuring regulatory and environmental standards are preserved.

Procurement Availability: The SN74HC74DBR is actively manufactured and stocked (5207 pcs in inventory versus 1058 pcs for the obsolete variant), providing superior supply chain reliability.

Functional Equivalence: All electrical parameters, timing characteristics, and functional capabilities remain identical, enabling direct board-level substitution without circuit redesign.

Packaging Compatibility: Identical 14-SSOP surface mount package ensures mechanical and thermal compatibility with existing PCB layouts and assembly processes.

Frequently Asked Questions (FAQ)

Q: Can the SN74HC74DBR be used as a direct replacement for the SN74HC74DB without circuit modifications?

A: Yes. The SN74HC74DBR is electrically and functionally identical to the SN74HC74DB across all specified parameters. Direct substitution is supported without circuit redesign or board layout changes.

Q: What is the difference between SN74HC74DB and SN74HC74DBR?

A: The primary difference is packaging format and product status. The SN74HC74DB is supplied in bulk packaging and is obsolete. The SN74HC74DBR is supplied in Cut Tape (CT) and Digi-Reel® formats and maintains active product status. All electrical and functional specifications are identical.

Q: Are there any thermal or reliability differences between these parts?

A: No. Both parts operate within the identical temperature range (-40°C to +85°C) and share identical thermal characteristics. Reliability and operating life are equivalent.

Q: Does the SN74HC74DBR meet the same compliance standards as the SN74HC74DB?

A: Yes. Both parts are ROHS3 compliant with MSL Level 1 rating. Regulatory and environmental compliance is maintained.

Q: What is the base product number for these parts?

A: The base product number is 74HC74, which identifies the core logic function. The SN74HC74DB and SN74HC74DBR are packaging and distribution variants of this base product.

Q: Can I use the SN74HC74DBR in high-frequency applications?

A: Yes. The SN74HC74DBR supports clock frequencies up to 60 MHz with maximum propagation delay of 30 ns at 6V with 50pF load, making it suitable for standard digital logic applications within this frequency range.

Q: Is the SN74HC74DBR suitable for low-power applications?

A: Yes. With quiescent current of 4 µA and supply voltage range of 2V to 6V, the SN74HC74DBR is appropriate for low-power digital logic designs.