74AC139SCX Equivalent & Substitute Parts

Part Overview

The 74AC139SCX is a Decoder/Demultiplexer logic integrated circuit manufactured by onsemi, featuring a 1 x 2:4 configuration in a 16-SOIC surface mount package. This component is classified as Active status and is ROHS3 compliant. Equivalent and substitute parts are identified based on matching electrical specifications, package compatibility, and functional equivalence within the 74AC logic family.

Substiute Parts

74AC139SCX

onsemiIn Stock: 3510074AC139SCX Datasheet

Current PartRFQ

MC74AC139DR2G

onsemiIn Stock: 3782MC74AC139DR2G Datasheet

DirectRFQ

MC74AC139DG

onsemiIn Stock: 1611MC74AC139DG Datasheet

SimilarRFQ

CD74AC139M

Harris CorporationIn Stock: 3704CD74AC139M Datasheet

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CD74AC139M96

Harris CorporationIn Stock: 2125CD74AC139M96 Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 74AC139SCX are qualified based on the following criteria:

Electrical Equivalence: All substitute parts maintain identical decoder/demultiplexer functionality with 1 x 2:4 circuit configuration, 2 independent circuits, and 24mA output current specifications.

Package Compatibility: All substitutes use the 16-SOIC surface mount package with identical 0.154" (3.90mm) width, ensuring PCB footprint compatibility.

Supply Voltage & Temperature: Substitutes operate within the specified 2V ~ 6V supply range and -40°C ~ 85°C temperature window, with some variants offering extended ranges.

Series Classification: All parts belong to the 74AC logic family, ensuring functional and timing compatibility.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitutes (Active Status, ROHS3 Compliant): MC74AC139DR2G and MC74AC139DG are direct functional equivalents manufactured by onsemi with Active product status and ROHS3 compliance. These parts are suitable for new designs and applications requiring current manufacturing support and regulatory compliance.

Secondary Substitutes (Obsolete Status, RoHS Non-Compliant): CD74AC139M and CD74AC139M96 are functionally equivalent but carry Obsolete status and RoHS non-compliance. These parts are suitable only for legacy system maintenance or applications where RoHS compliance is not required. The extended temperature range (-55°C ~ 125°C) and lower supply voltage floor (1.5V) provide broader operational margins compared to the primary part.

Packaging Considerations: Selection between MC74AC139DR2G (Tape & Reel), MC74AC139DG (Tube), and 74AC139SCX (Cut Tape & Digi-Reel) depends on procurement volume and assembly requirements. All three onsemi variants maintain identical electrical specifications and Active status.

Frequently Asked Questions (FAQ)

Q: Can MC74AC139DR2G replace 74AC139SCX directly? A: Yes. Both parts are manufactured by onsemi, share identical electrical specifications (2V ~ 6V supply, -40°C ~ 85°C operation), use the 16-SOIC package, and maintain ROHS3 compliance. The difference is packaging format: MC74AC139DR2G uses Tape & Reel while 74AC139SCX uses Cut Tape & Digi-Reel.

Q: Are the Harris Corporation parts (CD74AC139M, CD74AC139M96) suitable for new designs? A: No. Both Harris parts carry Obsolete status and RoHS non-compliance. They are suitable only for replacement in existing systems or legacy applications. For new designs, use active onsemi variants: MC74AC139DR2G or MC74AC139DG.

Q: What is the functional difference between these substitute parts? A: There is no functional difference. All parts implement identical 1 x 2:4 decoder/demultiplexer logic with 2 independent circuits and 24mA output current. Differences exist only in manufacturer, product status, packaging format, and compliance certifications.

Q: Can I use CD74AC139M in a 3.3V application? A: Yes. CD74AC139M operates within 1.5V ~ 5.5V supply range, which includes 3.3V. However, 74AC139SCX, MC74AC139DR2G, and MC74AC139DG are specified for 2V ~ 6V, which also accommodates 3.3V operation.

Q: What packaging format should I select for high-volume production? A: MC74AC139DR2G (Tape & Reel) is optimized for automated assembly. MC74AC139DG (Tube) is suitable for lower volumes or manual assembly. 74AC139SCX (Cut Tape & Digi-Reel) offers flexibility for mixed-volume requirements.