SN74S140D NAND Gate IC Equivalent & Substitute Parts

Part Overview

The SN74S140D is a NAND Gate IC featuring 2 channels with 4 inputs per channel in a 14-SOIC surface mount package, manufactured by Texas Instruments. This component is classified as Last Time Buy, indicating discontinued production with limited availability. Finding equivalent and substitute parts is necessary to ensure design continuity and maintain supply chain reliability for applications requiring NAND gate logic functionality.

Substiute Parts

SN74S140D

Texas InstrumentsIn Stock: 3333SN74S140D Datasheet

Current PartRFQ

SN74S140DR

Texas InstrumentsIn Stock: 982SN74S140DR Datasheet

MFR RecommendedRFQ

SN74S20D

Texas InstrumentsIn Stock: 1156SN74S20D Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the SN74S140D is determined by strict alignment of the following electrical and mechanical parameters:

• Logic Type: NAND Gate configuration
• Number of Circuits: 2 channels
• Number of Inputs: 4 inputs per channel
• Supply Voltage Range: 4.75V ~ 5.25V
• Package Type: 14-SOIC surface mount
• Operating Temperature Range: 0°C ~ 70°C
• Input Logic Levels: Low 0.8V, High 2V
• RoHS and REACH Compliance: ROHS3 Compliant, REACH Unaffected

The substitute parts listed below meet all these core parameters and are therefore functionally and mechanically compatible with the SN74S140D in applications requiring NAND gate logic.

Parameter Comparison

Engineering Selection Recommendations

SN74S140DR is the manufacturer-recommended substitute for the SN74S140D. Both parts share identical electrical specifications and package configuration. The primary distinction is packaging format: SN74S140D is supplied in Tube packaging, while SN74S140DR is supplied in Tape & Reel (TR) format. SN74S140DR maintains Active product status, ensuring ongoing availability and supply chain continuity. This part is the preferred choice for new designs and production continuity.

SN74S20D is a direct functional substitute meeting all core electrical and mechanical parameters. It is supplied in Tube packaging and maintains Active product status. While propagation delay and output current specifications differ from the SN74S140D, these variations remain within the allowable parameter range for NAND gate logic applications. Selection of SN74S20D should be based on specific application requirements and availability constraints.

Frequently Asked Questions (FAQ)

Q: Can SN74S140DR be used as a direct replacement for SN74S140D?

A: Yes. SN74S140DR is electrically and mechanically identical to SN74S140D. The only difference is packaging format (Tape & Reel versus Tube). Both are 14-SOIC surface mount packages with identical pin configurations and electrical characteristics.

Q: What is the difference between Tube and Tape & Reel packaging?

A: Tube packaging is used for lower-volume orders and manual assembly processes. Tape & Reel packaging is used for automated pick-and-place assembly. Both formats contain the same component; the choice depends on manufacturing process requirements.

Q: Is SN74S20D compatible with SN74S140D applications?

A: SN74S20D meets all core substitution criteria: NAND gate logic, 2 channels, 4 inputs per channel, 14-SOIC package, and identical supply voltage and operating temperature ranges. Propagation delay is 5ns versus 6ns, and output current specifications differ. Verify these performance differences against specific application requirements before selection.

Q: Why is SN74S140D marked as Last Time Buy?

A: Last Time Buy status indicates the manufacturer has discontinued production. Existing inventory is available, but no future production is planned. Transition to an Active substitute part such as SN74S140DR is recommended for long-term design continuity.

Q: Are all listed substitutes RoHS and REACH compliant?

A: Yes. All parts listed—SN74S140D, SN74S140DR, and SN74S20D—are ROHS3 Compliant and REACH Unaffected, meeting current environmental and regulatory requirements.