SN74ALS640BDW Equivalent & Substitute Parts

Part Overview

The SN74ALS640BDW is a transceiver integrated circuit manufactured by Texas Instruments, classified as a Logic component in the 74ALS series. This device functions as an inverting transceiver with 1 element, 8 bits per element, and 3-state output capability. The part is currently in Last Time Buy status, indicating limited availability and the necessity to identify equivalent or substitute components for ongoing design requirements and future production needs.

Substiute Parts

SN74ALS640BDW

Texas InstrumentsIn Stock: 2058SN74ALS640BDW Datasheet

Current PartRFQ

SN74ALS640BDWR

Texas InstrumentsIn Stock: 12117SN74ALS640BDWR Datasheet

MFR RecommendedRFQ

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 SN74ALS640BDW 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
• RoHS Status: ROHS3 Compliant
• Moisture Sensitivity Level (MSL): 1 (Unlimited)

Substitute parts are grouped into two categories: Manufacturer Recommended substitutes and Parametric Equivalents. All identified substitutes maintain identical electrical specifications and package dimensions, ensuring direct functional replacement in circuit applications.

Parameter Comparison

Engineering Selection Recommendations

SN74ALS640BDWR is the primary recommended substitute. This part maintains Active product status with Texas Instruments, ensuring continued availability and manufacturer support. All electrical and mechanical parameters are identical to the SN74ALS640BDW, with the primary distinction being the packaging designation suffix (R indicates tape and reel packaging versus tube packaging of the original part).

SN74ALS620ADW and SN74ALS620ADWG4 are parametric equivalents that satisfy all functional and electrical requirements. Both parts are manufactured by Texas Instruments in the 74ALS series with identical logic type, bit configuration, output characteristics, and supply voltage specifications. SN74ALS620ADW maintains Active status, while SN74ALS620ADWG4 is Discontinued at DiGi Electronics and should be considered only when other options are unavailable.

SN74ALS640B-1DW is classified as Obsolete and should not be selected for new designs or ongoing production. This part is included for reference only in legacy system maintenance scenarios.

Frequently Asked Questions (FAQ)

Q: Can SN74ALS640BDWR be used as a direct replacement for SN74ALS640BDW?

A: Yes. SN74ALS640BDWR is functionally and electrically identical to SN74ALS640BDW. The difference is packaging format: BDWR indicates tape and reel packaging, while BDW indicates tube packaging. Both are suitable for surface mount assembly in 20-SOIC packages.

Q: What is the difference between SN74ALS640BDW and SN74ALS620ADW?

A: Both parts are inverting transceivers with identical electrical specifications, output characteristics, and package dimensions. The base product numbers differ (640 versus 620), but all critical parameters for substitution are equivalent. Selection between these parts depends on availability and product status requirements.

Q: Why is SN74ALS640B-1DW listed if it is Obsolete?

A: SN74ALS640B-1DW is included for reference in applications where legacy components must be maintained or replaced in existing systems. This part should not be selected for new designs.

Q: Are all substitute parts ROHS3 compliant?

A: Yes. All listed substitute parts maintain ROHS3 compliance and Moisture Sensitivity Level 1 (Unlimited), meeting the same environmental and regulatory standards as the original SN74ALS640BDW.

Q: What packaging options are available among the substitutes?

A: SN74ALS640BDW is supplied in Tube packaging. SN74ALS640BDWR is supplied in Tape and Reel packaging. SN74ALS620ADW is supplied in Tube packaging. SN74ALS620ADWG4 and SN74ALS640B-1DW have unspecified packaging designations in available data. All parts use the identical 20-SOIC (0.295", 7.50mm Width) physical package.