74VHC74SJ Equivalent & Substitute Parts

Part Overview

The 74VHC74SJ is a dual D-type flip-flop logic integrated circuit manufactured by onsemi, housed in a 14-SOIC package with 0.209" (5.30mm) width. This component provides two independent D-type flip-flops with complementary outputs, set/preset and reset functions, and positive edge triggering. The part is classified as obsolete, making equivalent substitutes necessary for new designs and ongoing production requirements.

Substiute Parts

74VHC74SJ

onsemiIn Stock: 196974VHC74SJ Datasheet

Current PartRFQ

SN74AHC74NSR

Texas InstrumentsIn Stock: 3792SN74AHC74NSR Datasheet

DirectRFQ

SN74AHC74QDRG4Q1

Texas InstrumentsIn Stock: 3495SN74AHC74QDRG4Q1 Datasheet

UpgradeRFQ

74AHC74D,118

Nexperia USA Inc.In Stock: 471574AHC74D,118 Datasheet

SimilarRFQ

74AHCT74D-Q100J

Nexperia USA Inc.In Stock: 88974AHCT74D-Q100J Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 74VHC74SJ is determined by the following critical parameters:

• Logic Function: Dual D-type flip-flop with set/preset and reset capability
• Output Type: Complementary outputs
• Trigger Type: Positive edge triggered
• Clock Frequency: 115 MHz minimum
• Propagation Delay: 9.3 ns maximum @ 5V, 50pF load
• Supply Voltage Range: 2V ~ 5.5V compatibility
• Output Current: 8mA minimum (both high and low)
• Package Compatibility: 14-SOIC form factor
• Quiescent Current: 2 µA maximum

Substitute parts are grouped into three categories based on their relationship to the main part:

Direct Substitute: SN74AHC74NSR maintains identical electrical specifications and operates across the full 2V ~ 5.5V supply range with active product status.

Upgrade Substitute: SN74AHC74QDRG4Q1 provides automotive-grade qualification (AEC-Q100) with a narrower 14-SOIC package (0.154", 3.90mm width) and extended operating temperature to 125°C.

Similar Substitutes: 74AHC74D,118 and 74AHCT74D-Q100J offer compatible functionality with variations in supply voltage range and clock frequency specifications.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement: SN74AHC74NSR is the primary substitute for the obsolete 74VHC74SJ. It maintains identical electrical performance across the full 2V ~ 5.5V supply range, matching clock frequency and propagation delay specifications. The part is in active production status with ROHS3 compliance and unlimited moisture sensitivity level (MSL 1).

For Automotive Applications: SN74AHC74QDRG4Q1 is recommended when AEC-Q100 automotive qualification is required. This part provides extended operating temperature range to 125°C and features a narrower 14-SOIC package (0.154", 3.90mm width), which may require PCB layout verification for existing designs.

For Supply Voltage Constrained Designs: 74AHCT74D-Q100J is suitable only for applications operating within the 4.5V ~ 5.5V supply range. This part offers improved propagation delay (8.8 ns) and higher clock frequency (140 MHz) with automotive-grade qualification, but cannot operate at the lower voltage limits of the original 74VHC74SJ.

For General Industrial Use: 74AHC74D,118 provides active product status with full 2V ~ 5.5V supply compatibility and identical electrical specifications to the main part. This option is suitable for non-automotive applications requiring standard industrial temperature range.

Frequently Asked Questions (FAQ)

Q: Can SN74AHC74NSR be used as a direct drop-in replacement for 74VHC74SJ?

A: Yes. SN74AHC74NSR maintains identical electrical specifications including clock frequency (115 MHz), propagation delay (9.3 ns @ 5V, 50pF), supply voltage range (2V ~ 5.5V), and output current (8mA). The 14-SOIC package dimensions are identical (0.209", 5.30mm width), enabling direct PCB substitution.

Q: What is the difference between the 74AHC and 74AHCT series?

A: The 74AHCT series (represented by 74AHCT74D-Q100J) is optimized for TTL-level input compatibility and operates within a narrower supply voltage range (4.5V ~ 5.5V). The 74AHC series supports the full 2V ~ 5.5V range. Both series maintain identical output current and quiescent current specifications.

Q: Why does SN74AHC74QDRG4Q1 have a different package width?

A: SN74AHC74QDRG4Q1 uses a narrower 14-SOIC package (0.154", 3.90mm width) compared to the original 74VHC74SJ (0.209", 5.30mm width). While both are 14-pin SOIC packages, the reduced width may require PCB layout verification. Pin pitch and electrical connections remain compatible.

Q: Is the 74VHC74SJ suitable for new designs?

A: No. The 74VHC74SJ is classified as obsolete. New designs should use active alternatives such as SN74AHC74NSR for standard applications or SN74AHC74QDRG4Q1 for automotive-qualified designs.

Q: What is the input capacitance difference between substitute parts?

A: The main part 74VHC74SJ specifies 4 pF input capacitance, while substitute parts range from 2 pF to 3 pF. Lower input capacitance in substitutes may reduce loading effects on driving circuits, which is generally beneficial for signal integrity.

Q: Can 74AHCT74D-Q100J operate at 2V supply voltage?

A: No. 74AHCT74D-Q100J operates only within the 4.5V ~ 5.5V supply range. For applications requiring 2V ~ 5.5V operation, use SN74AHC74NSR or 74AHC74D,118 instead.

Q: Are all substitute parts ROHS3 compliant?

A: Yes. All listed substitute parts (SN74AHC74NSR, SN74AHC74QDRG4Q1, 74AHC74D,118, and 74AHCT74D-Q100J) are ROHS3 compliant with MSL 1 (unlimited) moisture sensitivity level.