74LVC646ADB,112 Equivalent & Substitute Parts

Part Overview

The 74LVC646ADB,112 is a non-inverting transceiver logic IC manufactured by NXP USA Inc., designed for 8-bit bidirectional data transfer with 3-state output capability. This component operates across a supply voltage range of 1.2V to 3.6V and is housed in a 24-SSOP package. The part is currently classified as obsolete, making equivalent substitute parts necessary for ongoing design requirements and production continuity.

Substiute Parts

74LVC646ADB,112

NXP USA Inc.In Stock: 83674LVC646ADB,112 Datasheet

Current PartRFQ

SN74LVC646ADBR

Texas InstrumentsIn Stock: 26359SN74LVC646ADBR Datasheet

MFR RecommendedRFQ

SN74LVC646APW

Texas InstrumentsIn Stock: 1211SN74LVC646APW Datasheet

MFR RecommendedRFQ

SN74LVC646APWR

Texas InstrumentsIn Stock: 859SN74LVC646APWR Datasheet

MFR RecommendedRFQ

SN74LVC646APWT

Texas InstrumentsIn Stock: 899SN74LVC646APWT Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 74LVC646ADB,112 are qualified based on the following critical parameters that determine functional and mechanical compatibility:

Core Electrical Parameters:

• Logic Type: Transceiver, Non-Inverting
• Number of Elements: 1
• Number of Bits per Element: 8
• Output Type: 3-State
• Current - Output High, Low: 24mA, 24mA
• Series: 74LVC

Voltage and Temperature Compatibility:

• Voltage - Supply: Minimum 1.65V (substitute parts operate within the original 1.2V ~ 3.6V range)
• Operating Temperature: -40°C ~ 85°C (substitute parts support the lower temperature bound of the original specification)

Package Compatibility: Substitutes are grouped into two package categories:

1. 24-SSOP Package (0.209", 5.30mm Width) - Direct footprint replacement
2. 24-TSSOP Package (0.173", 4.40mm Width) - Alternate thin-profile package with identical pin configuration

All substitute parts maintain ROHS3 compliance, MSL Level 1, and active or recently discontinued product status, ensuring availability and regulatory alignment.

Parameter Comparison

Engineering Selection Recommendations

For Direct Footprint Replacement (24-SSOP Package): SN74LVC646ADBR from Texas Instruments is the primary substitute for the 74LVC646ADB,112. This part maintains identical package dimensions (24-SSOP, 0.209" width), electrical specifications, and ROHS3 compliance. The part is currently in active production status with substantial inventory availability (26,346 pcs), ensuring supply chain continuity.

For Space-Constrained Designs (24-TSSOP Package): SN74LVC646APW and SN74LVC646APWR provide equivalent electrical functionality in a thinner 24-TSSOP package (0.173" width). These parts are suitable for applications where PCB real estate optimization is required. SN74LVC646APW is supplied in tube packaging, while SN74LVC646APWR is supplied in tape and reel format for automated assembly. Both maintain active product status.

Voltage and Temperature Considerations: All Texas Instruments substitutes operate within a reduced voltage range (1.65V ~ 3.6V) compared to the original NXP part (1.2V ~ 3.6V). Applications requiring operation below 1.65V supply voltage cannot use these substitutes. Additionally, substitute parts are rated to -40°C ~ 85°C, compared to the original -40°C ~ 125°C specification. Applications requiring operation above 85°C must retain the original NXP part or identify alternative solutions.

Frequently Asked Questions (FAQ)

Q: Can SN74LVC646ADBR be used as a direct replacement for 74LVC646ADB,112? A: Yes. SN74LVC646ADBR is electrically and mechanically compatible with identical 24-SSOP package dimensions, matching output current specifications (24mA), and equivalent 3-state transceiver functionality. Both parts are ROHS3 compliant with MSL Level 1 rating.

Q: What is the difference between SN74LVC646APW and SN74LVC646APWR? A: Both parts are electrically identical with the same 24-TSSOP package. The difference is packaging format: SN74LVC646APW is supplied in tube packaging for manual handling, while SN74LVC646APWR is supplied in tape and reel format optimized for automated pick-and-place assembly.

Q: Can I use the 24-TSSOP package substitutes (SN74LVC646APW/APWR) on a PCB designed for 24-SSOP? A: No. The 24-TSSOP package (0.173" width) has different physical dimensions than the 24-SSOP package (0.209" width). PCB footprints are not interchangeable. A new PCB layout is required for TSSOP variants.

Q: Are there voltage supply limitations when using Texas Instruments substitutes? A: Yes. Texas Instruments substitutes operate at 1.65V ~ 3.6V supply voltage, while the original NXP part operates at 1.2V ~ 3.6V. If your application requires operation below 1.65V, the original NXP part or alternative solutions must be used.

Q: What is the maximum operating temperature for substitute parts? A: Texas Instruments substitutes are rated to -40°C ~ 85°C. The original NXP part is rated to -40°C ~ 125°C. Applications requiring operation above 85°C cannot use these substitutes.

Q: Is SN74LVC646APWT still available for new designs? A: SN74LVC646APWT is discontinued at DiGi Electronics with 883 pcs in current inventory. While limited stock exists, this part is not recommended for new production designs. Use SN74LVC646APWR (tape and reel) or SN74LVC646APW (tube) for ongoing availability.