74ACTQ374QSC Equivalent & Substitute Parts

Part Overview

The 74ACTQ374QSC is a D-Type flip-flop logic integrated circuit manufactured by onsemi, featuring 1 element with 8-bit positive edge triggering and tri-state non-inverted output. This component is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing design support and production continuity. The part operates within a 4.5V to 5.5V supply range with a maximum propagation delay of 9ns at 5V with 50pF load, housed in a 20-LSSOP surface mount package.

Substiute Parts

74ACTQ374QSC

onsemiIn Stock: 91274ACTQ374QSC Datasheet

Current PartRFQ

CY74FCT374TQCT

Texas InstrumentsIn Stock: 1004CY74FCT374TQCT Datasheet

SimilarRFQ

SN74ACT374DBR

Texas InstrumentsIn Stock: 2186SN74ACT374DBR Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 74ACTQ374QSC is determined by the following critical parameters:

• Functional Type: D-Type flip-flop with 1 element, 8-bit configuration, positive edge trigger
• Output Configuration: Tri-state, non-inverted output
• Electrical Compatibility: Supply voltage range, propagation delay, output drive capability, quiescent current
• Package Compatibility: Surface mount 20-pin configuration with compatible pinout
• Operating Temperature Range: -40°C to 85°C

The identified substitute parts maintain functional equivalence across these core parameters while accommodating minor variations in electrical performance and packaging dimensions that remain within acceptable design tolerances.

Parameter Comparison

Engineering Selection Recommendations

SN74ACT374DBR (Texas Instruments) is the primary substitute for the 74ACTQ374QSC. Both parts share identical supply voltage range (4.5V ~ 5.5V), output drive capability (24mA, 24mA), and input capacitance (4.5 pF). The SN74ACT374DBR offers superior performance with faster propagation delay (8.5ns versus 9ns) and significantly lower quiescent current (4 µA versus 40 µA). The part maintains active product status with ROHS3 compliance and unlimited moisture sensitivity rating. Package dimensions differ (0.209" versus 0.154" width), requiring PCB layout verification for physical fit.

CY74FCT374TQCT (Texas Instruments) serves as an alternative substitute with matching package dimensions (0.154", 3.90mm width) to the original part. This part maintains functional equivalence with compatible propagation delay (10ns, within acceptable tolerance) and positive edge trigger operation. However, the CY74FCT374TQCT exhibits higher quiescent current (200 µA) and asymmetrical output drive capability (32mA high, 64mA low), with a narrower supply voltage range (4.75V ~ 5.25V). The part carries ROHS3 compliance but requires one-year moisture sensitivity management (MSL 2).

Both substitute parts are active products from Texas Instruments with established supply availability, addressing the obsolescence status of the original onsemi component.

Frequently Asked Questions (FAQ)

Q: Can the SN74ACT374DBR directly replace the 74ACTQ374QSC without design modifications?

A: Functional replacement is supported. The SN74ACT374DBR maintains identical logic function, supply voltage range, output configuration, and operating temperature range. Physical package dimensions differ (0.209" versus 0.154" width), requiring PCB footprint verification and potential layout adjustments. Electrical performance is superior, with faster propagation delay and lower quiescent current.

Q: What are the key differences between the two substitute options?

A: The SN74ACT374DBR offers better electrical performance (8.5ns propagation delay, 4 µA quiescent current) but requires package footprint changes. The CY74FCT374TQCT maintains the original package dimensions (0.154" width) but exhibits higher quiescent current (200 µA), asymmetrical output drive, and narrower supply voltage tolerance (4.75V ~ 5.25V). Selection depends on whether package compatibility or electrical performance optimization is prioritized.

Q: Are there supply voltage compatibility concerns with either substitute?

A: The SN74ACT374DBR operates within the identical supply range (4.5V ~ 5.5V) as the original part. The CY74FCT374TQCT operates within a narrower range (4.75V ~ 5.25V). If the design requires operation at 4.5V or 5.5V extremes, the SN74ACT374DBR is the appropriate choice.

Q: What is the impact of different quiescent current specifications?

A: The SN74ACT374DBR draws significantly less quiescent current (4 µA versus 40 µA for the original, and 200 µA for the CY74FCT374TQCT). In battery-powered or low-power applications, the SN74ACT374DBR provides superior power efficiency. In standard applications, this difference is typically negligible.

Q: Are both substitutes RoHS compliant?

A: Both the SN74ACT374DBR and CY74FCT374TQCT are ROHS3 compliant, meeting current environmental and regulatory requirements. The original 74ACTQ374QSC RoHS status is not specified.

Q: What moisture sensitivity considerations apply to these parts?

A: The SN74ACT374DBR carries MSL 1 (unlimited shelf life), matching the original part. The CY74FCT374TQCT carries MSL 2 (one-year shelf life), requiring controlled storage and handling procedures. For applications with extended component storage requirements, the SN74ACT374DBR is preferred.