DM74ALS640AWM Equivalent & Substitute Parts

Part Overview

The DM74ALS640AWM is a logic transceiver IC manufactured by onsemi, featuring inverting functionality with 1 element, 8 bits per element, and 3-state output capability. This component operates within the 4.5V to 5.5V supply voltage range and is housed in a 20-SOIC package. The part is currently classified as obsolete, making identification of equivalent and substitute components essential for ongoing design support and production continuity.

Substiute Parts

DM74ALS640AWM

onsemiIn Stock: 2543DM74ALS640AWM Datasheet

Current PartRFQ

SN74ALS640BDW

Texas InstrumentsIn Stock: 2058SN74ALS640BDW Datasheet

DirectRFQ

SN74ALS640BDWR

Texas InstrumentsIn Stock: 12117SN74ALS640BDWR Datasheet

DirectRFQ

SN74ALS640B-1DWR

Texas InstrumentsIn Stock: 800SN74ALS640B-1DWR Datasheet

SimilarRFQ

SN74ALS640B-1NSR

Texas InstrumentsIn Stock: 3545SN74ALS640B-1NSR Datasheet

SimilarRFQ

SN74ALS640BNSR

Texas InstrumentsIn Stock: 3399SN74ALS640BNSR Datasheet

SimilarRFQ

SN74ALS620ADW

Texas InstrumentsIn Stock: 1098SN74ALS620ADW Datasheet

Parametric EquivalentRFQ

SN74ALS620ADWG4

Texas InstrumentsIn Stock: 997SN74ALS620ADWG4 Datasheet

Parametric EquivalentRFQ

SN74ALS640B-1DW

Texas InstrumentsIn Stock: 1155SN74ALS640B-1DW Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the DM74ALS640AWM is determined by strict equivalence across the following critical parameters:

• Logic Type: Transceiver, Inverting
• Number of Elements: 1
• Number of Bits per Element: 8
• Output Type: 3-State
• Current - Output High, Low: 15mA, 24mA
• Voltage - Supply: 4.5V ~ 5.5V
• Operating Temperature: 0°C ~ 70°C (TA)
• Package / Case: 20-SOIC (0.295", 7.50mm Width)
• Mounting Type: Surface Mount

Substitute parts are categorized as follows:

Direct Manufacturer Substitutes: Parts that maintain identical electrical and mechanical specifications with the main part, differing only in manufacturer or product status.

Similar Manufacturer Substitutes: Parts that maintain core functional parameters but may differ in package width or supplier device package designation while remaining electrically compatible.

Parametric Equivalents: Parts that share the same base product number or functional characteristics but may have different package dimensions or product status classifications.

Parameter Comparison

Engineering Selection Recommendations

For applications currently using the DM74ALS640AWM, the following selection criteria apply based on product status and compliance:

Primary Recommendation: SN74ALS640BDWR (Texas Instruments) is the preferred substitute. This part maintains active product status, is ROHS3 compliant, and provides the highest inventory availability (12,088 pcs). The identical electrical and mechanical specifications ensure direct functional replacement.

Secondary Recommendation: SN74ALS640B-1DWR (Texas Instruments) offers active product status and ROHS3 compliance with adequate inventory (774 pcs). This part is supplied in Tape & Reel packaging, suitable for automated assembly processes.

Alternative for Specific Packaging Requirements: SN74ALS640B-1NSR and SN74ALS640BNSR (Texas Instruments) provide active product status and ROHS3 compliance but feature a narrower 20-SO package (0.209" width) compared to the standard 20-SOIC (0.295" width). These parts are suitable only if PCB layout accommodates the reduced package width.

Parametric Equivalent Option: SN74ALS620ADW (Texas Instruments) maintains active product status and ROHS3 compliance with identical electrical specifications and standard package dimensions. This part operates as a functional equivalent with a different base product number.

Parts with obsolete or discontinued status (SN74ALS640B-1DW, SN74ALS620ADWG4) should be considered only when active alternatives are unavailable and existing inventory is confirmed.

Frequently Asked Questions (FAQ)

Q: Can SN74ALS640BDWR be used as a direct replacement for DM74ALS640AWM?

A: Yes. Both parts share identical electrical specifications (1 element, 8 bits per element, 3-state output, 15mA/24mA output current, 4.5V–5.5V supply, 0°C–70°C operating range) and the same package type (20-SOIC, 0.295" width). The primary difference is manufacturer (Texas Instruments vs. onsemi) and product status (active vs. obsolete).

Q: What is the difference between SN74ALS640BDWR and SN74ALS640B-1NSR?

A: Both parts are functionally equivalent with identical electrical specifications. The key difference is package width: SN74ALS640BDWR uses a standard 20-SOIC package (0.295" width), while SN74ALS640B-1NSR uses a narrower 20-SO package (0.209" width). PCB layout compatibility must be verified before selecting the narrower package variant.

Q: Why is SN74ALS620ADW listed as a substitute if it has a different base product number?

A: SN74ALS620ADW is classified as a parametric equivalent because it maintains all critical electrical and mechanical specifications required for functional substitution: identical logic type, element count, bit width, output type, current ratings, voltage supply range, operating temperature, and package dimensions. The different base product number reflects a design variant within the 74ALS series that provides equivalent performance.

Q: Are all substitute parts ROHS3 compliant?

A: All Texas Instruments substitute parts listed are ROHS3 compliant. The original onsemi part (DM74ALS640AWM) is classified as REACH Unaffected. Compliance status should be verified against specific procurement requirements.

Q: What packaging options are available for substitutes?

A: Substitute parts are available in three packaging formats: Tube (SN74ALS640BDW, SN74ALS620ADW), Tape & Reel (SN74ALS640BDWR, SN74ALS640B-1DWR, SN74ALS640B-1NSR, SN74ALS640BNSR). Selection depends on assembly process requirements and order quantities.

Q: Which substitute has the highest current inventory?

A: SN74ALS640BDWR maintains the highest inventory availability at 12,088 pcs, followed by SN74ALS640B-1NSR at 3,458 pcs and SN74ALS640BNSR at 3,300 pcs.