CD74AC138M Equivalent & Substitute Parts

Part Overview

The CD74AC138M is a Decoder/Demultiplexer logic IC manufactured by Texas Instruments, featuring a 1 x 3:8 circuit configuration in a 16-SOIC surface mount package. This part is discontinued at DiGi Electronics, making equivalent substitute parts necessary for ongoing design requirements and production needs. The 74AC138 series decoder/demultiplexer is widely used in digital logic applications requiring address decoding and signal routing functions.

Substiute Parts

CD74AC138M

Texas InstrumentsIn Stock: 1525CD74AC138M Datasheet

Current PartRFQ

CD74AC138M96

Texas InstrumentsIn Stock: 4147CD74AC138M96 Datasheet

DirectRFQ

MC74AC138DR2G

onsemiIn Stock: 2842MC74AC138DR2G Datasheet

DirectRFQ

74AC138SC

Fairchild SemiconductorIn Stock: 221274AC138SC Datasheet

MFR RecommendedRFQ

74AC138SCX

onsemiIn Stock: 2792374AC138SCX Datasheet

MFR RecommendedRFQ

MC74AC138DG

onsemiIn Stock: 1884MC74AC138DG Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the CD74AC138M is determined by strict equivalence across the following critical parameters:

• Base Product Number: All substitutes must be 74AC138 series devices
• Circuit Configuration: 1 x 3:8 decoder/demultiplexer topology
• Package Type: 16-SOIC surface mount package with 0.154" (3.90mm) width
• Output Current Capability: 24mA high and low output current
• Voltage Supply Source: Single supply operation
• Mounting Type: Surface mount technology

The substitute parts listed below meet these core electrical and mechanical requirements. Variations in operating temperature range and supply voltage limits exist among manufacturers but do not affect functional substitution within their respective rated specifications.

Parameter Comparison

Engineering Selection Recommendations

CD74AC138M96 (Texas Instruments): Direct manufacturer alternative with identical electrical specifications and extended temperature range (-55°C ~ 125°C). Active product status with ROHS3 compliance and MSL 1 rating. Recommended for applications requiring Texas Instruments sourcing continuity.

MC74AC138DR2G (onsemi): Active onsemi product in Cut Tape & Digi-Reel packaging. Meets all functional requirements with ROHS3 compliance. Operating temperature range -40°C ~ 85°C and supply voltage 2V ~ 6V are suitable for standard industrial applications.

74AC138SC (Fairchild Semiconductor): Active product with identical output current specifications. Suitable for applications where Fairchild sourcing is preferred. RoHS status not specified in available data.

74AC138SCX (onsemi): Active onsemi product with highest inventory availability (27,900 pcs). ROHS3 compliant with MSL 1 rating. Cut Tape & Digi-Reel packaging supports high-volume production requirements.

MC74AC138DG (onsemi): Active onsemi product supplied in Tube packaging. ROHS3 compliant with MSL 1 rating. Suitable for applications where tube packaging is preferred for component handling and storage.

Selection should prioritize active products with ROHS3 compliance and MSL 1 ratings. Operating temperature and supply voltage ranges must be verified against specific application requirements.

Frequently Asked Questions (FAQ)

Q: Can CD74AC138M be directly replaced with CD74AC138M96?

A: Yes. Both are Texas Instruments 74AC138 decoders in 16-SOIC packages with identical output current (24mA), single supply operation, and ROHS3 compliance. CD74AC138M96 is the active product continuation.

Q: What is the difference between onsemi and Fairchild 74AC138 variants?

A: All variants maintain the same 1 x 3:8 decoder/demultiplexer circuit, 24mA output current, and 16-SOIC package. Operating temperature ranges differ: onsemi and Fairchild parts operate -40°C ~ 85°C, while Texas Instruments parts extend to -55°C ~ 125°C. Supply voltage ranges also vary slightly (2V ~ 6V for onsemi/Fairchild vs. 1.5V ~ 5.5V for TI).

Q: Are all substitute parts ROHS3 compliant?

A: Five of six substitute parts carry explicit ROHS3 compliance certification. The 74AC138SC (Fairchild) does not specify RoHS status in available documentation. Verify compliance requirements for your application before selection.

Q: What packaging options are available for 74AC138 substitutes?

A: Packaging varies by manufacturer: CD74AC138M96 and MC74AC138DR2G are supplied in Cut Tape & Digi-Reel format; 74AC138SCX is Cut Tape & Digi-Reel; MC74AC138DG is supplied in Tube; 74AC138SC packaging is not specified. Select based on production volume and handling requirements.

Q: Can I use a 74AC138 variant with a narrower operating temperature range in a wide-temperature application?

A: No. Applications requiring -55°C ~ 125°C operation must use Texas Instruments parts (CD74AC138M96 or CD74AC138M). onsemi and Fairchild variants are rated only to -40°C ~ 85°C and are not suitable for extended temperature requirements.

Q: Are all substitute parts functionally identical in circuit operation?

A: Yes. All parts implement the same 1 x 3:8 decoder/demultiplexer logic with 24mA output current capability and single supply operation. Functional behavior is identical within their respective rated operating conditions.