74ACTQ244QSC Equivalent & Substitute Parts

Part Overview

The 74ACTQ244QSC is a non-inverting buffer logic IC manufactured by onsemi, featuring 2 elements with 4 bits per element and 3-state output capability. This component is classified as obsolete, making equivalent substitute parts necessary for ongoing design support and procurement. The part operates within a 4.5V to 5.5V supply voltage range and is rated for -40°C to 85°C operating temperature. Surface mount packaging in 20-QSOP configuration provides compact integration for digital logic applications requiring buffering and signal isolation.

Substiute Parts

74ACTQ244QSC

onsemiIn Stock: 427574ACTQ244QSC Datasheet

Current PartRFQ

CD74ACT244SM96

Texas InstrumentsIn Stock: 884CD74ACT244SM96 Datasheet

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SN74ACT244DBR

Texas InstrumentsIn Stock: 4507SN74ACT244DBR Datasheet

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SN74ACT244PW

Texas InstrumentsIn Stock: 2307SN74ACT244PW Datasheet

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SN74ACT244PWE4

Texas InstrumentsIn Stock: 878SN74ACT244PWE4 Datasheet

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SN74ACT244PWR

Texas InstrumentsIn Stock: 45441SN74ACT244PWR Datasheet

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SN74LVCH244ADBQR

Texas InstrumentsIn Stock: 3006SN74LVCH244ADBQR Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 74ACTQ244QSC is determined by strict equivalence across the following critical parameters:

• Logic Type: Buffer, Non-Inverting
• Number of Elements: 2
• Number of Bits per Element: 4
• Output Type: 3-State
• Current - Output High, Low: 24mA, 24mA
• Voltage - Supply: 4.5V ~ 5.5V
• Operating Temperature: -40°C ~ 85°C (TA)
• Mounting Type: Surface Mount

Substitute parts are grouped into two categories based on voltage supply compatibility:

Group 1 (5V Logic Family): Parts operating within 4.5V ~ 5.5V supply range, maintaining full electrical equivalence with the original 74ACTQ244QSC specification.

Group 2 (Low-Voltage Logic Family): Parts with reduced supply voltage range (1.65V ~ 3.6V), suitable for applications where lower voltage operation is acceptable and backward compatibility with 5V systems is not required.

Parameter Comparison

Engineering Selection Recommendations

Primary Recommendation: SN74ACT244PWR (Texas Instruments) is the preferred substitute for the obsolete 74ACTQ244QSC. This part maintains full electrical equivalence across all critical parameters, carries Active product status ensuring long-term availability, and holds ROHS3 compliance certification. With 45,400 units in stock, procurement reliability is established.

Secondary Recommendation: SN74ACT244DBR (Texas Instruments) provides equivalent functionality with Active product status and ROHS3 compliance. The 20-SSOP package offers a compact footprint alternative to the 20-TSSOP configuration of the primary recommendation.

Alternative for Low-Voltage Applications: SN74LVCH244ADBQR (Texas Instruments) is suitable only when system design permits operation within 1.65V to 3.6V supply voltage range. This part maintains identical logic functionality and output drive capability but operates at reduced voltage levels. Active product status and ROHS3 compliance are confirmed.

Discontinued Parts: CD74ACT244SM96, SN74ACT244PW, and SN74ACT244PWE4 are discontinued at DiGi Electronics and should be avoided for new designs despite electrical equivalence.

Frequently Asked Questions (FAQ)

Q: Can SN74ACT244PWR directly replace 74ACTQ244QSC in existing designs?

A: Yes. Both parts maintain identical logic type, element count, bit configuration, output type, drive current, supply voltage range, and operating temperature specifications. The 20-TSSOP package of the SN74ACT244PWR is functionally compatible with the 20-QSOP package of the original part, though PCB layout modifications may be required due to different package footprints.

Q: What is the difference between the 20-QSOP, 20-SSOP, and 20-TSSOP packages?

A: These are surface mount package variants with different physical dimensions. 20-QSOP (0.154" width) and 20-SSOP (0.209" width) differ in body width, while 20-TSSOP (0.173" width) represents a thin shrink variant. All three accommodate 20 pins with identical electrical connectivity. Package selection depends on available PCB real estate and design constraints.

Q: Is SN74LVCH244ADBQR a suitable replacement for the 74ACTQ244QSC?

A: SN74LVCH244ADBQR is electrically equivalent in logic function but operates at reduced supply voltage (1.65V ~ 3.6V versus 4.5V ~ 5.5V). Use this part only if your system design operates within the lower voltage range. It is not suitable as a direct replacement in 5V systems without additional voltage regulation circuitry.

Q: Why is the 74ACTQ244QSC marked as obsolete?

A: Obsolete status indicates the manufacturer has discontinued production. Active alternatives from Texas Instruments ensure continued design support and component availability for equivalent functionality.

Q: Are all substitute parts ROHS3 compliant?

A: All Texas Instruments substitute parts listed carry ROHS3 compliance certification. The original 74ACTQ244QSC does not specify ROHS status in the provided data.

Q: What is the MSL (Moisture Sensitivity Level) difference between parts?

A: The 74ACTQ244QSC and most 74ACT variants carry MSL 1 (Unlimited), indicating no moisture sensitivity restrictions. The SN74LVCH244ADBQR carries MSL 2 (1 Year), requiring storage within controlled humidity conditions for one year from manufacturing date.