SN74LS640DWR Equivalent & Substitute Parts

Part Overview

The SN74LS640DWR is a logic transceiver IC manufactured by Texas Instruments, classified as an inverting transceiver with 1 element and 8 bits per element. The device features 3-state output capability and operates within the 4.75V to 5.25V supply voltage range. Currently in active product status with 3400 units in stock, this component is widely used in digital logic applications requiring signal inversion and tri-state control.

The SN74LS640DW represents an equivalent substitute option. However, this part carries a Last Time Buy product status, indicating limited future availability. Identifying suitable alternatives ensures design continuity and supply chain reliability for applications currently utilizing the SN74LS640DWR.

Substiute Parts

SN74LS640DWR

Texas InstrumentsIn Stock: 3497SN74LS640DWR Datasheet

Current PartRFQ

SN74LS640DW

Texas InstrumentsIn Stock: 3328SN74LS640DW Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the SN74LS640DWR 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: 4.75V ~ 5.25V
• Operating Temperature: 0°C ~ 70°C (TA)
• Package / Case: 20-SOIC (0.295", 7.50mm Width)
• Mounting Type: Surface Mount

The SN74LS640DW meets all electrical and mechanical substitution criteria. Both parts share identical functional specifications, pin configurations, and performance characteristics. The primary distinction is product lifecycle status: the SN74LS640DWR maintains active status with current production, while the SN74LS640DW is designated Last Time Buy.

Parameter Comparison

Engineering Selection Recommendations

The SN74LS640DW is electrically and mechanically equivalent to the SN74LS640DWR. Both parts satisfy identical functional requirements and are suitable for direct substitution in circuit designs. Both components maintain ROHS3 compliance and REACH unaffected status, meeting regulatory requirements for industrial and commercial applications.

For new designs and long-term production requirements, the SN74LS640DWR is the preferred selection due to its active product status and ongoing availability. The SN74LS640DW remains a valid substitute for existing inventory management or short-term procurement needs, provided that Last Time Buy constraints are factored into supply chain planning.

Frequently Asked Questions (FAQ)

Q: Can the SN74LS640DW be used as a direct replacement for the SN74LS640DWR?

A: Yes. Both parts are electrically and mechanically identical. They share the same logic type, element configuration, bit width, output characteristics, supply voltage range, operating temperature range, and 20-SOIC package specifications. Direct substitution is supported without circuit modification.

Q: What is the significance of the product status difference between these parts?

A: The SN74LS640DWR maintains active production status, ensuring continued availability and supply. The SN74LS640DW is designated Last Time Buy, indicating that production will cease and future availability is limited. For applications requiring long-term component sourcing, the SN74LS640DWR is the recommended choice.

Q: Are there any compliance or certification differences between these parts?

A: No. Both parts are ROHS3 compliant, REACH unaffected, and carry identical moisture sensitivity levels (MSL 1 - Unlimited). Regulatory and environmental compliance requirements are met by both components.

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

A: Substitution is based on matching logic type (Transceiver, Inverting), element count (1), bit width (8 bits per element), output type (3-State), output current specifications (15mA high, 24mA low), supply voltage range (4.75V ~ 5.25V), and operating temperature range (0°C ~ 70°C).

Q: Are the package and mounting specifications identical?

A: Yes. Both parts use the 20-SOIC package with 0.295" (7.50mm) width and surface mount mounting type. PCB footprints and assembly processes are identical.