74ACTQ573SC D-Type Transparent Latch Equivalent & Substitute Parts

Part Overview

The 74ACTQ573SC is a D-Type Transparent Latch IC manufactured by onsemi, featuring an 8:8 circuit configuration with tri-state output capability in a 20-SOIC package. This component is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and production continuity. The part operates within a 4.5V to 5.5V supply voltage range with a propagation delay of 6.5ns and supports output currents of 24mA for both high and low states across an operating temperature range of -40°C to 85°C.

Substiute Parts

74ACTQ573SC

onsemiIn Stock: 129174ACTQ573SC Datasheet

Current PartRFQ

MC74ACT573DWG

onsemiIn Stock: 1184MC74ACT573DWG Datasheet

SimilarRFQ

MC74ACT573DWR2G

onsemiIn Stock: 2225MC74ACT573DWR2G Datasheet

SimilarRFQ

CD74ACT573M

Harris CorporationIn Stock: 2217CD74ACT573M Datasheet

SimilarRFQ

CD74ACT573M96

Harris CorporationIn Stock: 1927CD74ACT573M96 Datasheet

SimilarRFQ

SN74ACT573DWR

Texas InstrumentsIn Stock: 14076SN74ACT573DWR Datasheet

SimilarRFQ

SN74ACT573NSR

Texas InstrumentsIn Stock: 2810SN74ACT573NSR Datasheet

SimilarRFQ

SN74ACT563DW

Texas InstrumentsIn Stock: 1647SN74ACT563DW Datasheet

Parametric EquivalentRFQ

SN74ACT573DW

Texas InstrumentsIn Stock: 2818SN74ACT573DW Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 74ACTQ573SC is determined by the following critical parameters:

Primary Substitution Criteria:

• Logic Type: D-Type Transparent Latch
• Circuit Configuration: 8:8
• Output Type: Tri-State
• Voltage Supply Range: 4.5V ~ 5.5V
• Package Type: 20-SOIC with 0.295" (7.50mm) width
• Output Current Capability: 24mA minimum (both high and low)
• Operating Temperature Range: Minimum -40°C to 85°C

Secondary Compatibility Factors:

• Propagation Delay: 6ns to 6.5ns acceptable range
• Independent Circuits: 1 channel
• Mounting Type: Surface Mount

Parts meeting all primary criteria are classified as direct substitutes. The 74ACTQ573SC can be replaced with components sharing identical circuit configuration (8:8), package dimensions, and electrical specifications. Parts with different circuit configurations (such as 1:8) or package variants (such as 20-SO with 0.209" width) are classified as parametric equivalents with design considerations.

Parameter Comparison

Engineering Selection Recommendations

Direct Substitutes (8:8 Configuration, 20-SOIC 0.295" Package):

SN74ACT573DWR and SN74ACT573DW from Texas Instruments are the primary recommended substitutes. Both maintain the 8:8 circuit configuration, identical package dimensions, and equivalent propagation delay specifications (6ns versus 6.5ns). SN74ACT573DWR is actively produced and available in Tape & Reel packaging with ROHS3 compliance and MSL 1 rating. SN74ACT573DW is discontinued at DiGi Electronics but remains available through alternative channels with identical electrical specifications.

SN74ACT563DW from Texas Instruments is a parametric equivalent with identical electrical performance and package specifications. This part is in Last Time Buy status and offers full compatibility with the 74ACTQ573SC.

CD74ACT573M and CD74ACT573M96 from Harris Corporation are obsolete alternatives with superior propagation delay (3.1ns) and extended operating temperature range (-55°C to 125°C). These parts are not RoHS compliant and should be selected only when legacy system requirements mandate their use.

Parametric Equivalents (1:8 Configuration, 20-SOIC 0.295" Package):

MC74ACT573DWG and MC74ACT573DWR2G from onsemi feature a 1:8 circuit configuration instead of 8:8, resulting in different functional behavior. These parts are actively produced with ROHS3 compliance but exhibit higher propagation delay (10.5ns) and MSL 3 moisture sensitivity. Selection of these parts requires circuit redesign validation.

Package Variant (8:8 Configuration, 20-SO 0.209" Package):

SN74ACT573NSR from Texas Instruments maintains the 8:8 circuit configuration with identical electrical specifications but uses a narrower 20-SO package (0.209" width versus 0.295"). This part is actively produced with ROHS3 compliance and MSL 1 rating. PCB layout modification is required for this package variant.

Frequently Asked Questions (FAQ)

Q: Can I use MC74ACT573DWG or MC74ACT573DWR2G as direct replacements for the 74ACTQ573SC?

A: No. While these parts share the same package footprint and electrical supply specifications, they feature a 1:8 circuit configuration instead of 8:8. This fundamental difference in circuit topology requires circuit redesign and functional validation. These parts are classified as parametric equivalents, not direct substitutes.

Q: What is the difference between SN74ACT573DWR and SN74ACT573DW?

A: Both parts are electrically identical with 8:8 configuration, 20-SOIC package, and 6ns propagation delay. The primary difference is packaging format: SN74ACT573DWR is supplied in Tape & Reel (TR) format for automated assembly, while SN74ACT573DW is supplied in Tube format for manual handling. SN74ACT573DWR is currently active production; SN74ACT573DW is discontinued at DiGi Electronics.

Q: Why does SN74ACT573NSR have a different package width (0.209" versus 0.295")?

A: SN74ACT573NSR uses a 20-SO package instead of 20-SOIC. Both are 20-pin surface-mount packages, but the SO variant has a narrower body width. This requires PCB layout modification and cannot be used as a drop-in replacement without board redesign.

Q: Are the Harris Corporation parts (CD74ACT573M and CD74ACT573M96) suitable for new designs?

A: Both Harris parts are obsolete and not RoHS compliant. They should not be selected for new designs. These parts are appropriate only for legacy system maintenance where existing designs mandate their use. Texas Instruments and onsemi alternatives are recommended for all new applications.

Q: What is the significance of the propagation delay differences between substitute parts?

A: Propagation delay ranges from 3.1ns (Harris parts) to 10.5ns (onsemi 1:8 variants). The 74ACTQ573SC specifies 6.5ns. Texas Instruments substitutes (6ns) and the SN74ACT563DW (6.5ns) maintain equivalent timing performance. Harris parts offer faster response; onsemi 1:8 variants are slower. Timing-critical applications must validate propagation delay specifications against system requirements.

Q: What does MSL 1 versus MSL 3 mean for component handling?

A: MSL (Moisture Sensitivity Level) 1 indicates unlimited shelf life without moisture control. MSL 3 requires controlled storage and has a 168-hour floor life after opening. The 74ACTQ573SC and most Texas Instruments substitutes are MSL 1. onsemi 1:8 variants (MC74ACT573DWG and MC74ACT573DWR2G) are MSL 3, requiring stricter moisture management during assembly.

Q: Can I mix different substitute parts in the same production run?

A: Parts with identical circuit configuration (8:8), package dimensions (20-SOIC 0.295"), and electrical specifications can be used interchangeably within the same design. However, mixing parts with different circuit configurations (8:8 versus 1:8) or package variants (0.295" versus 0.209" width) requires separate board designs and functional validation.