74ACTQ273SCX Equivalent & Substitute Parts

Part Overview

The 74ACTQ273SCX is a D-type flip-flop logic integrated circuit manufactured by onsemi, featuring 1 element with 8-bit configuration and positive edge triggering. This component is classified as obsolete, which necessitates identification of functionally equivalent active alternatives for new designs and ongoing production requirements. The part operates within the 4.5V to 5.5V supply voltage range and is housed in a 20-SOIC surface mount package.

Substiute Parts

74ACTQ273SCX

onsemiIn Stock: 202274ACTQ273SCX 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 of the 74ACTQ273SCX is determined by strict equivalence across the following critical parameters:

Mandatory Matching Parameters:

• Function: Master Reset
• Type: D-Type Flip Flop
• Number of Elements: 1
• Number of Bits per Element: 8
• Output Type: Non-Inverted
• Trigger Type: Positive Edge
• Voltage - Supply: 4.5V ~ 5.5V
• Current - Output High, Low: 24 mA, 24 mA
• Package / Case: 20-SOIC (0.295", 7.50mm Width)
• Mounting Type: Surface Mount

Allowable Parameter Variations:

• Clock Frequency: May exceed 189 MHz
• Max Propagation Delay: May be equal to or less than 8.5 ns
• Current - Quiescent (Iq): May be lower than 40 µA
• Input Capacitance: May vary within acceptable logic design tolerances
• Operating Temperature: May extend beyond -40°C ~ 85°C
• Product Status: Active status preferred for new designs
• Moisture Sensitivity Level: May differ based on manufacturing process

All identified substitute parts meet these criteria and maintain functional and electrical compatibility with the 74ACTQ273SCX.

Parameter Comparison

Engineering Selection Recommendations

For Active Production and New Designs:

The MC74ACT273DWG and MC74ACT273DWR2G (both onsemi) are recommended as primary substitutes. Both parts maintain active product status, achieve ROHS3 compliance, and provide improved quiescent current performance (8 µA versus 40 µA). The primary distinction between these two onsemi alternatives is packaging: MC74ACT273DWG is supplied in Tube packaging, while MC74ACT273DWR2G is supplied in Tape & Reel format. Selection between these should be based on assembly process requirements and inventory management practices.

For Extended Temperature Range Applications:

The CD74ACT273M96 (Texas Instruments) extends the operating temperature range to -55°C ~ 125°C, providing broader environmental coverage compared to the standard -40°C ~ 85°C specification. This part achieves ROHS3 compliance and maintains MSL 1 (Unlimited) moisture sensitivity rating. The trade-off is reduced clock frequency (80 MHz) and increased propagation delay (14.6 ns), which may not be suitable for timing-critical applications.

Compliance Considerations:

All substitute parts maintain REACH Unaffected status and EAR99 ECCN classification consistent with the original 74ACTQ273SCX. ROHS3 compliance is achieved by all active alternatives, supporting modern supply chain and environmental regulatory requirements.

Frequently Asked Questions (FAQ)

Q: Can MC74ACT273DWG and MC74ACT273DWR2G be used interchangeably with the 74ACTQ273SCX?

A: Yes. Both parts are electrically and functionally equivalent to the 74ACTQ273SCX. The difference between them is packaging format only: Tube versus Tape & Reel. Electrical performance and pin configuration are identical.

Q: What is the impact of the increased propagation delay in the MC74ACT273DWG and MC74ACT273DWR2G?

A: The propagation delay increases from 8.5 ns to 11 ns. This 2.5 ns difference is acceptable in most standard logic applications. Applications with timing margins less than 2.5 ns should be evaluated individually.

Q: Is the CD74ACT273M96 suitable for all applications requiring the 74ACTQ273SCX?

A: The CD74ACT273M96 is functionally compatible but exhibits reduced clock frequency (80 MHz versus 189 MHz) and increased propagation delay (14.6 ns). It is suitable for applications where timing performance is not critical. The extended operating temperature range (-55°C ~ 125°C) makes it preferable for extreme environment applications.

Q: What is the significance of the quiescent current reduction in the substitute parts?

A: The substitute parts reduce quiescent current from 40 µA to 8 µA, representing an 80% reduction in standby power consumption. This improvement is beneficial for battery-powered and low-power applications.

Q: Are there packaging compatibility concerns when substituting the 74ACTQ273SCX?

A: No. All substitute parts use the identical 20-SOIC (0.295", 7.50mm Width) package with surface mount configuration. PCB footprints and assembly processes remain unchanged.

Q: What is the difference between MSL 1 and MSL 3 moisture sensitivity ratings?

A: MSL 1 (Unlimited) allows indefinite storage without moisture control. MSL 3 (168 Hours) requires moisture control and limits storage to 168 hours after packaging opening. The onsemi alternatives (MC74ACT273DWG and MC74ACT273DWR2G) with MSL 3 require standard moisture management practices during assembly.