74ACTQ273SC Equivalent & Substitute Parts

Part Overview

The 74ACTQ273SC is a D-type flip-flop logic integrated circuit manufactured by onsemi, designed for 8-bit parallel data storage with positive edge triggering. This component features a master reset function and operates across the 4.5V to 5.5V supply voltage range. The part is currently classified as obsolete, making equivalent substitute parts necessary for ongoing system support and new design implementations. Substitute components must maintain functional compatibility while meeting current manufacturing and compliance standards.

Substiute Parts

74ACTQ273SC

onsemiIn Stock: 105774ACTQ273SC Datasheet

Current PartRFQ

MC74ACT273DWG

onsemiIn Stock: 2296MC74ACT273DWG Datasheet

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MC74ACT273DWR2G

onsemiIn Stock: 2342MC74ACT273DWR2G Datasheet

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CD74ACT273M96

Texas InstrumentsIn Stock: 1481CD74ACT273M96 Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 74ACTQ273SC is determined by strict adherence to the following core parameters: D-type flip-flop architecture with 8-bit configuration, positive edge triggering, non-inverted output, master reset function, 20-SOIC package format, 4.5V to 5.5V supply voltage compatibility, and surface mount technology. All qualified substitute parts maintain these electrical and mechanical specifications. Variations in clock frequency, propagation delay, quiescent current, and operating temperature range do not disqualify substitution when the core functional parameters remain constant. Packaging format (tube, tape & reel) represents a logistics distinction rather than a functional incompatibility.

Parameter Comparison

Engineering Selection Recommendations

All three substitute parts—MC74ACT273DWG, MC74ACT273DWR2G, and CD74ACT273M96—are classified as active products with current manufacturing support. The onsemi variants (MC74ACT273DWG and MC74ACT273DWR2G) are functionally identical, differing only in packaging format: tube versus tape & reel. Both achieve ROHS3 compliance and demonstrate reduced quiescent current (8 µA versus 40 µA) compared to the obsolete 74ACTQ273SC.

The Texas Instruments CD74ACT273M96 offers extended operating temperature range (-55°C to 125°C) and maintains MSL 1 rating identical to the original part. This variant exhibits lower clock frequency (80 MHz) and higher propagation delay (14.6ns), with increased input capacitance (10 pF). Selection between onsemi and Texas Instruments variants depends on temperature range requirements and supply chain availability.

Frequently Asked Questions (FAQ)

Q: Can MC74ACT273DWG and MC74ACT273DWR2G be used interchangeably with 74ACTQ273SC?

A: Yes. Both parts maintain identical electrical specifications and 20-SOIC package format. The difference between tube (DWG) and tape & reel (DWR2G) packaging is a logistics consideration only and does not affect functional compatibility.

Q: What is the impact of the CD74ACT273M96's lower clock frequency (80 MHz versus 189 MHz)?

A: The 80 MHz clock frequency of the Texas Instruments part remains suitable for standard 74ACT logic applications. The higher propagation delay (14.6ns) must be evaluated against system timing requirements. This part is appropriate for applications not requiring the higher speed of the original or onsemi alternatives.

Q: Does the increased input capacitance (10 pF) of the CD74ACT273M96 affect circuit design?

A: Input capacitance affects signal rise time and driver loading. The 10 pF specification of the Texas Instruments part versus 4.5 pF of other variants requires verification against driver capabilities in timing-critical applications.

Q: Why do the onsemi substitutes show lower quiescent current (8 µA versus 40 µA)?

A: The reduction in quiescent current reflects manufacturing process improvements in active production variants compared to the obsolete 74ACTQ273SC. This represents a beneficial characteristic for power consumption in standby conditions.

Q: Are there temperature range limitations when substituting with MC74ACT273DWG or MC74ACT273DWR2G?

A: Both onsemi variants maintain the -40°C to 85°C operating range of the original part. The CD74ACT273M96 extends this to -55°C to 125°C, providing additional thermal margin for demanding environments.

Q: What is the significance of MSL rating differences?

A: The original part and CD74ACT273M96 carry MSL 1 (unlimited moisture sensitivity), while onsemi variants are MSL 3 (168 hours). MSL 3 components require controlled storage and handling within 168 hours of package opening. Selection depends on manufacturing environment and storage capabilities.