CD74HC138M Equivalent & Substitute Parts

Part Overview

The CD74HC138M is a 1 x 3:8 decoder/demultiplexer logic integrated circuit manufactured by Texas Instruments in a 16-SOIC surface mount package. This part is currently discontinued at DiGi Electronics, making equivalent substitutes necessary for ongoing design and production requirements. The 74HC138 series decoder functions as a 3-to-8 line decoder with demultiplexing capability, operating across a 2V to 6V supply range with symmetric output current characteristics.

Substiute Parts

CD74HC138M

Texas InstrumentsIn Stock: 1272CD74HC138M Datasheet

Current PartRFQ

CD74HC138M96

Texas InstrumentsIn Stock: 2920CD74HC138M96 Datasheet

DirectRFQ

CD74HC238M

Harris CorporationIn Stock: 1479CD74HC238M Datasheet

Parametric EquivalentRFQ

MC74HC138ADR2G

onsemiIn Stock: 18583MC74HC138ADR2G Datasheet

DirectRFQ

MM74HC138M

onsemiIn Stock: 1220MM74HC138M Datasheet

DirectRFQ

74HC138D,653

Nexperia USA Inc.In Stock: 8809774HC138D,653 Datasheet

MFR RecommendedRFQ

74HC138D-Q100,118

Nexperia USA Inc.In Stock: 841874HC138D-Q100,118 Datasheet

MFR RecommendedRFQ

74HC138S16-13

Diodes IncorporatedIn Stock: 353574HC138S16-13 Datasheet

MFR RecommendedRFQ

MM74HC138MX

Fairchild SemiconductorIn Stock: 29362MM74HC138MX Datasheet

MFR RecommendedRFQ

MC74HC138ADG

onsemiIn Stock: 3615MC74HC138ADG Datasheet

Parametric EquivalentRFQ

MC74HC238ADG

onsemiIn Stock: 1298MC74HC238ADG Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the CD74HC138M is determined by the following critical parameters:

• Circuit configuration (1 x 3:8 decoder/demultiplexer function)
• Output current specifications (5.2mA high and low)
• Supply voltage range (2V to 6V minimum)
• Package type (16-SOIC surface mount)
• Operating temperature range compatibility
• RoHS and compliance certifications

Substitute parts are grouped into three categories: direct manufacturer equivalents from Texas Instruments, parametric equivalents from alternative manufacturers meeting identical electrical specifications, and manufacturer-recommended alternatives with extended or automotive-grade qualifications.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitutes (Identical Specifications)

CD74HC138M96 is the direct Texas Instruments equivalent with active product status, identical electrical specifications, and ROHS3 compliance. This part maintains the full -55°C to 125°C operating range and is available in higher quantities through Cut Tape and Digi-Reel packaging.

MC74HC138ADR2G from onsemi provides the highest inventory availability (18498 Pcs) with matching electrical parameters, full temperature range, and ROHS3 compliance. This part is suitable for high-volume production requirements.

Extended Temperature Range Alternatives

74HC138D,653 and 74HC138D-Q100,118 from Nexperia USA Inc. maintain the full -40°C to 125°C operating range with ROHS3 compliance and active product status. The Q100 variant includes AEC-Q100 automotive qualification for applications requiring automotive-grade components.

Restricted Temperature Range Options

MM74HC138M and MM74HC138MX from onsemi and Fairchild Semiconductor operate within -40°C to 85°C, representing a narrower temperature envelope. These parts are suitable only for applications not requiring the extended -55°C lower temperature limit.

Obsolete and Non-Compliant Parts

CD74HC238M from Harris Corporation is obsolete and RoHS non-compliant. This part should not be selected for new designs or production requiring current compliance certifications.

Frequently Asked Questions (FAQ)

Q: Can I substitute CD74HC138M with any 74HC138 variant?

A: No. Substitution requires matching the circuit configuration (1 x 3:8), output current (5.2mA), supply voltage range (2V to 6V), and package type (16-SOIC). Operating temperature range must meet or exceed your application requirements. Parts with narrower temperature ranges (MM74HC138M, MM74HC138MX) are not suitable if your design requires -55°C operation.

Q: What is the difference between CD74HC138M96 and CD74HC138M?

A: Both are Texas Instruments 74HC138 decoders with identical electrical specifications and operating ranges. The primary difference is packaging format: CD74HC138M is supplied in Tube packaging, while CD74HC138M96 is available in Cut Tape and Digi-Reel formats. CD74HC138M96 has active product status versus discontinued status for the original part.

Q: Are there RoHS compliance differences between substitutes?

A: Yes. Most active substitutes are ROHS3 compliant. CD74HC238M from Harris Corporation is RoHS non-compliant and should not be used in applications requiring RoHS certification. MM74HC138MX does not specify RoHS status and should be verified with the manufacturer before use in compliant applications.

Q: Which substitute has the best availability?

A: 74HC138D,653 from Nexperia USA Inc. has the highest inventory (88009 Pcs) with active product status, ROHS3 compliance, and full -40°C to 125°C operating range. MC74HC138ADR2G from onsemi (18498 Pcs) is the second-highest availability option.

Q: Can I use automotive-grade parts in non-automotive applications?

A: Yes. The 74HC138D-Q100,118 with AEC-Q100 qualification meets or exceeds standard commercial specifications and can be used in non-automotive designs. This part provides additional qualification assurance without functional or electrical differences.

Q: What packaging options are available for substitutes?

A: Substitutes are available in Tube, Cut Tape & Digi-Reel, and Tape & Reel formats. Selection depends on production volume and assembly equipment compatibility. High-volume production typically uses Tape & Reel or Cut Tape formats, while lower volumes may use Tube packaging.