SN74ACT240DBR Equivalent & Substitute Parts

Part Overview

The SN74ACT240DBR is an inverting buffer logic integrated circuit manufactured by Texas Instruments, designed for digital signal buffering and inversion applications. This device features 2 elements with 4 bits per element and 3-state output capability, operating across a 4.5V to 5.5V supply voltage range. The part is currently in active production status with 3,110 units available in new original inventory. Equivalent and substitute parts are identified to provide design flexibility, support supply chain continuity, and accommodate varying packaging or sourcing requirements while maintaining functional and electrical compatibility.

Substiute Parts

SN74ACT240DBR

Texas InstrumentsIn Stock: 3146SN74ACT240DBR Datasheet

Current PartRFQ

74ACT240MTC

Fairchild SemiconductorIn Stock: 2673674ACT240MTC Datasheet

MFR RecommendedRFQ

74ACT240MTCX

onsemiIn Stock: 5575674ACT240MTCX Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SN74ACT240DBR are qualified based on strict electrical and mechanical compatibility criteria. All substitute parts must maintain identical functional characteristics: 2-element, 4-bit inverting buffer configuration with 3-state output capability. Electrical parameters including output current (24mA high and low), supply voltage range (4.5V ~ 5.5V), and operating temperature range (-40°C ~ 85°C) must be equivalent across all qualified substitutes.

The base product number 74ACT240 is common to all qualified substitutes, confirming functional equivalence. Packaging variations are permitted only when the substitute part maintains surface mount technology and compatible pin configurations. All substitute parts listed are active production items with confirmed inventory availability and maintain equivalent RoHS3 compliance and MSL ratings.

Parameter Comparison

Engineering Selection Recommendations

All three parts maintain active production status and are electrically equivalent across core functional parameters. The SN74ACT240DBR and 74ACT240MTCX both carry ROHS3 compliance certification and MSL Level 1 ratings, confirming equivalent environmental and regulatory compliance. The 74ACT240MTC from Fairchild Semiconductor provides functional equivalence with identical electrical specifications but does not specify RoHS or MSL compliance in the provided data.

Package differences exist between the main part (20-SSOP, 5.30mm width) and the two substitute options (20-TSSOP, 4.40mm width). The TSSOP package is narrower and represents a more compact form factor. PCB layout and footprint compatibility must be verified before substitution, as the different package widths require distinct land pattern designs.

Selection should prioritize parts with confirmed compliance certifications matching the original design requirements. Inventory availability is substantial across all three options, supporting immediate procurement without supply constraints.

Frequently Asked Questions (FAQ)

Q: Are the 74ACT240MTC and 74ACT240MTCX direct pin-for-pin replacements for the SN74ACT240DBR?

A: All three parts share the same base product number (74ACT240) and maintain identical pin counts and functional configurations. However, package geometry differs: the SN74ACT240DBR uses 20-SSOP packaging (5.30mm width), while both substitutes use 20-TSSOP packaging (4.40mm width). Pin-to-pin electrical compatibility is confirmed, but PCB footprints are not interchangeable without layout redesign.

Q: What are the key electrical parameters that define substitution eligibility?

A: Substitution is based on matching: logic type (Buffer, Inverting), element count (2), bits per element (4), output type (3-State), output current ratings (24mA high and low), supply voltage range (4.5V ~ 5.5V), and operating temperature range (-40°C ~ 85°C). All listed substitutes meet these criteria.

Q: Does the Fairchild 74ACT240MTC meet the same compliance standards as the original part?

A: The Fairchild part does not specify RoHS or MSL compliance in the provided data. If design requirements mandate ROHS3 compliance and MSL Level 1 certification, the onsemi 74ACT240MTCX is the preferred substitute, as it matches both certifications of the original Texas Instruments part.

Q: Can I use the narrower TSSOP package substitutes in an existing design without modification?

A: No. The TSSOP package (4.40mm width) differs from the SSOP package (5.30mm width), requiring distinct PCB footprints and land patterns. Physical board redesign is necessary for package substitution.

Q: Are all three parts currently available in production quantities?

A: Yes. The SN74ACT240DBR has 3,110 units in stock, the 74ACT240MTC has 26,648 units, and the 74ACT240MTCX has 55,730 units available as new original inventory.